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Master ThesisManagement & Control of Home AutomationDevices based on EnOcean Technology with                  JSLEE       ...
StatementI confirm that the master thesis is written by me without any assistant. No other sources wereused except those r...
Acknowledgement        It gives me immense pleasure to thank all, who made this thesis to be accomplished.Firstly, I would...
Content1        Scope of Work                                                                                             ...
3       Requirement Analysis                                                                                              ...
1             Scope of WorkThe scope of the Master Thesis research work is to integrate the home automation communi-cating...
2            Theoretical Foundation2.1          EnOcean TechnologyIn this section of the thesis, a detailed description of...
2.1 EnOcean Technology                                                                        82.1.2         An Overview o...
2.1 EnOcean Technology                                                                                        92.1.1 Figur...
2.1 EnOcean Technology                                                                      10Figure 2.1.2: Energy Harvest...
2.1 EnOcean Technology                                                                         11Figure 2.1.3: Wireless Se...
2.1 EnOcean Technology                                                                      12system end receives this sig...
2.1 EnOcean Technology                                                                                     13Figure 2.1.4:...
2.1 EnOcean Technology                                                                            14EnOcean Technology Tec...
2.1 EnOcean Technology                                                                 15Figure 2.1.5: EnOcean Wireless Ne...
2.1 EnOcean Technology                                                                  16Figure 2.1.6 EnOcean Technology ...
2.1 EnOcean Technology                                                                    17Figure 2.1.7: Transmission rel...
2.1 EnOcean Technology                                                                     18EnOcean. It receives all sign...
2.1 EnOcean Technology                                                                       19         dio shadow is buil...
2.1 EnOcean Technology                                                                         20    2) 2001: This port is...
2.1 EnOcean Technology                                                                            21Considering the functi...
2.1 EnOcean Technology                                                                    22After, completing the connecti...
2.1 EnOcean Technology                                                                                       23          T...
2.1 EnOcean Technology                                                                   242.1.7            Wireless singl...
2.1 EnOcean Technology                                                                     252.1.8            Wireless Swi...
2.1 EnOcean Technology                                                                      26Figure 2.1.14: Wireless Brig...
2.1 EnOcean Technology                                                                     27However, in this chapter the ...
2.1 EnOcean Technology                                                                     28Figure 2.1.16: Detail Descrip...
2.1 EnOcean Technology                                                                       29          figure 2.1.16, in...
2.1 EnOcean Technology                                                                    302.1.18, shows a table of the s...
2.2 Transmission Control Protocol (TCP)                                                   31    6) Network Layer: This lay...
2.2 Transmission Control Protocol (TCP)                                                     322.2.1         TCP Flow Contr...
2.2 Transmission Control Protocol (TCP)                                                                     33            ...
2.3 Session Initiation Protocol                                                                         34                ...
2.3 Session Initiation Protocol                                                                             35The logic of...
2.3 Session Initiation Protocol                                                                              36   UPDATE  ...
2.3 Session Initiation Protocol                                                               372.3.1         Network Elem...
2.3 Session Initiation Protocol                                                            38Figure 2.3.1 A simple peer to...
2.3 Session Initiation Protocol                                                            39back user agent which means t...
2.4 Convedia Media Server                                                                    40As mentioned in [3261], a “...
2.4 Convedia Media Server                                                                   412.4.1         Media Server M...
2.4 Convedia Media Server                                                                    42Figure 2.4.1 Example of a M...
2.5 JAIN Service Logic Execution Environment                                               43nection through the applicati...
2.5 JAIN Service Logic Execution Environment                                                44JAIN is supposed to integrat...
2.5 JAIN Service Logic Execution Environment                                                45Figure 2.5.1: JSLEE Architec...
2.5 JAIN Service Logic Execution Environment                                              46step 4, more child SBBs can be...
2.5 JAIN Service Logic Execution Environment                                               472.5.3           Service Build...
2.5 JAIN Service Logic Execution Environment                                               482.5.4            Event, Event...
2.5 JAIN Service Logic Execution Environment                                                 49that generated the event of...
2.5 JAIN Service Logic Execution Environment                                               50Figure 2.5.5: Example of the ...
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Managemant & Control of Home Automation Devices based on EnOcean Technology with JSLEE

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  1. 1. Master ThesisManagement & Control of Home AutomationDevices based on EnOcean Technology with JSLEE Submitted by: Piyush Chand Submitted to: Prof. Dr. Ulrich Trick & Dr. Andreas Pech Date of Submission: 14th October 2011
  2. 2. StatementI confirm that the master thesis is written by me without any assistant. No other sources wereused except those referenced.Frankfurt, 14.10.2011_____________________Piyush Chand
  3. 3. Acknowledgement It gives me immense pleasure to thank all, who made this thesis to be accomplished.Firstly, I would like to acknowledge Professor Dr.-Ing.Ulrich Trick for giving me an oppor-tunity to work and write my thesis at the Research Group of Telecommunications, Frankfurtam Main. The experience has been highly acknowledging and pleasuring. I would also like to express my gratitude towards my supervisors, especially to Tho-mas Eichelmann for his skilful guidance, motivation and support during the progress of thethesis work. I am also thankful to Armin Lehmann, Patrick Wacht and Patrick Ruhrig for theirskilful guidance, in depth discussions, moral support and maintaining a pleasant environmentduring the progress of the thesis work, On a personal note, I would like to thank my parents and my uncle for their moralsupport and encouragement. In the end, I would like to offer my regards to everyone who supported me during thecompletion of the thesis work.
  4. 4. Content1 Scope of Work 62 Theoretical Foundation 72.1 EnOcean Technology ............................................................................................. 72.1.1 Brief History of EnOcean Technology .................................................................... 72.1.2 An Overview of EnOcean Technology .................................................................... 82.1.3 EnOcean Communication Architecture ................................................................. 142.1.4 EnOcean Technology based Gateway ................................................................... 172.1.5 BSC-BAP-TX Access Point.................................................................................. 192.1.6 Wireless Actuator ................................................................................................. 222.1.7 Wireless single-phase energy meter ...................................................................... 242.1.8 Wireless Switch/Push-button ................................................................................ 252.1.9 Wireless Motion/brightness sensor ........................................................................ 252.1.10 EnOcean Equipment Profiles ................................................................................ 262.1.11 Standardization of EnOcean Radio Protocol .......................................................... 292.1.12 EnOcean Technology Summary............................................................................ 312.2 Transmission Control Protocol (TCP) ................................................................... 312.2.1 TCP Flow Control ................................................................................................ 322.2.2 TCP State ............................................................................................................. 332.3 Session Initiation Protocol .................................................................................... 342.3.1 Network Elements of SIP ..................................................................................... 372.3.2 Back to Back User Agent (B2BUA) ...................................................................... 382.3.3 SIP Dialog............................................................................................................ 392.4 Convedia Media Server ........................................................................................ 402.4.1 Media Server Mark up Language .......................................................................... 412.4.2 Media Server Control Channel.............................................................................. 422.5 JAIN Service Logic Execution Environment ......................................................... 432.5.1 JAIN (Java API for Integrated Networks) ............................................................. 432.5.2 Service Delivery Platform..................................................................................... 442.5.3 Service Building Block(SBB) ............................................................................... 472.5.4 Event, Event Routing............................................................................................ 482.5.5 Activity and Activity Context Interface ................................................................. 492.6 Resource Adaptor ................................................................................................. 512.6.1 Resource Adaptor Type ........................................................................................ 532.6.2 Resource Adaptor Entity....................................................................................... 542.6.3 Resource Adaptor Entity Life Cycle...................................................................... 542.6.4 Resource Adaptor Object Life Cycle ..................................................................... 56
  5. 5. 3 Requirement Analysis 583.1 General Objective ................................................................................................. 583.2 Objective of the Implementation ........................................................................... 583.3 Required Technologies ......................................................................................... 603.3.1 Hardware based Requirements: ............................................................................. 603.3.2 Software based Requirements: .............................................................................. 614 Realization 624.1 Installing Mobicents Application server ................................................................ 634.2 Installing Wireshark ............................................................................................. 644.3 EnOcean Resource Adaptor .................................................................................. 644.4 EnOcean Event Module ........................................................................................ 684.5 EnOcean Resource Adaptor Module ..................................................................... 694.6 EnOcean Activity & SIP Activity ......................................................................... 724.7 Activity Handler Module ...................................................................................... 734.8 EnOcean Service Building Block(SBB) ................................................................ 844.9 EnOcean Service Example.................................................................................... 914.9.1 DTMF functionality with EnOcean Service........................................................... 934.9.2 EnOcean ServiceAnnouncement Call .................................................................... 934.9.3 Announcement Call to turn Light On .................................................................... 944.9.4 Announcement Call to turn Light Off.................................................................... 955 Project Summary & Future Perspectives 975.1 Project Summary .................................................................................................. 975.2 Future Perspectives............................................................................................... 986 Abbreviations 1037 References 106
  6. 6. 1 Scope of WorkThe scope of the Master Thesis research work is to integrate the home automation communi-cating architecture to the telecommunication architecture. The research provides the founda-tion of developing value added services for controlling and monitoring home automationdevices by a SIP (Session Initiation Protocol) [3261] UA (User Agent). The work demon-strates a service by which a user can control and manage the home automation devices basedon EnOcean Technology by a SIP UA. The home automation devices are based on actuatorsand sensors. The initial part of the thesis work is to develop an EnOcean Resource Adaptoron the bases of JAIN SLEE (Java API for Integrated Networks Service Logic ExecutionEnvironment) [Jain], this allows the Application Server to communicate with the EnOceanGateway. To evaluate the integration, a service based on the specification of [Jain] is devel-oped. The service is developed to control the home devices like lamp, motion sensor andenergy meter with add on media functionality like an IVR (Interactive Voice Response)system to control the house hold devices. This scenario of implementation provides a possi-bility of integrating the smart home devices to the telecommunication architecture. A furtherextension of this research work can be to set up a completely new set of value added servicesthrough which a user can demonstrate services like controlling their house hold deviceswhich include light, motion sensors, energy meter by mobile devices.The control of these devices is introduced as a service for the SIP UA. The research workprovides the possibility of more services for the user like IVR system for controlling household devices, announcement calls for motion detection, announcement calls for various sen-sors in the home etc. The complete functionality of integrating the home automation devicesto the telecommunication architecture depends upon the EnOcean Gateway which is an Ac-cess point and industrial name is BSC-BAP-TX (Wireless Bolt Access Point) [Bscb]. Thegateway provision provides a possibility of an application server to be integrated to the EnO-cean gateway on the bases of TCP/IP [1180], the handling of the TCP/IP is done by theEnOcean Resource Adaptor. The gateway can communicate with home automation devicesover RF (Radio Frequency). As, the communication is established between the applicationserver, services can be developed by which management, monitoring, controlling can bedone by SIP UA or a Web user based on HTTP (Hyper Text Transfer Protocol) [2616].
  7. 7. 2 Theoretical Foundation2.1 EnOcean TechnologyIn this section of the thesis, a detailed description of the EnOcean[Enoc1] Technology isprovided. This section gives all the important and necessary information which includestechnical behaviour, working principle, EnOcean Technology supporting devices, advan-tages, special features of EnOcean Technology. To provide home automation environment tothe user various technologies are in use one of the popular technology is the EnOcean Tech-nology, this technology allows user to completely automate their home devices based onsensors and actuators. The main innovation behind this technology is to harvest the energyfrom the environment and then utilize that energy to create some activity like controllingdevices in the home that are controlled by actuators and sensors.2.1.1 Brief History of EnOcean TechnologyEnOcean is gradually becoming popular in developing automation devices for homes andofficial buildings. As mentioned in [Enoc1] the EnOcean Alliance Group was founded byManagement & Siemens Technology Acceorometer. The EnOcean GmbH is a venture-funded spin-off company of Siemens AG founded in 2001. It is a technology supplier of self-powered modules like transmitters, receivers, transceivers, energy converter to companieslike Siemens, Distech Controls, Seamless Sensing which develop and manufacture productsused in building home automation devices for example light, shading, HVAC(Heat Ventila-tion and Air Conditioner) and also industrial based automation like replacement of the con-ventional battery in tyre pressure sensors. As mentioned in [Enoc1] the company has wonawards for its performance and technology including the Bavarian Innovation Prize 2002 forits globally unique technology.
  8. 8. 2.1 EnOcean Technology 82.1.2 An Overview of EnOcean TechnologyThe EnOcean Technology is based on providing Energy Harvesting wireless technology. Asmentioned in [Enoc2] the EnOcean Technology can broadly be divided to three major advan-tageous divisions:  Interoperable wireless standard: Monitoring and lighting control systems are readily available and wide-ranging product portfolio exists, based on an interoperable stan- dard technology together with interfaces to established automation solutions such as EIB (European Instalation Bus) that is a standard for home automation devices in europe and TCP /IP (Transmission Control Protocol /Internet protocol) [1180].  Self-powered: The EnOcean devices are based on Energy Harvesting which makes the use of energy created from slight changes in motion, pressure, light, temperature or vibration. The self-powered wireless sensors help make buildings smarter, safer, more comfortable and more energy-efficient.  Technology for sustainable buildings: EnOcean enabled wireless networks making it the most pervasive and field-tested wireless building automation standard.As described in [Enoc1], EnOcean Technology is based on the energetically efficient exploi-tation of applied slight mechanical excitation and other potentials from the environmentusing the principles of energy harvesting. In order to transform such energy fluctuations intousable electrical energy based on some electrical principles like Electromagnetic which is aphysical field produced by electrically charged objects. Piezogenerator: It is the chargewhich accumulates in certain solid materials like notably crystals, certain ceramics. Solar cellalso known as photovoltaic cell or photoelectric cell is a solid state electrical device thatconverts the energy of light directly into electricity by the photovoltaic effect Thermocouple,It is a device consisting of two different conductors (usually metal alloys) that produce avoltage proportional to a temperature difference between either ends of the pair of conduc-tors. The EnOcean products are engineered to operate maintenance-free.The transmission frequency used for the devices is 868.3 MHz which is a standard for homeautomation devices. The EnOcean RF modules based on energy harvesting modules arefundamentally based on consuming very low power electronics and reliable wireless trans-mission. A small example scenario demonstrating the EnOcean Technology is shown infigure 2.1.1.
  9. 9. 2.1 EnOcean Technology 92.1.1 Figure showing a complete optimizing heating and cooling solution based on EnOcean Technology [Enoc3]Figure 2.1.1, shows a complete EnOcean based heating and cooling solution. The figureconsists of a Energy control which communicates with all the devices like Room temperaturesensor, humidity sensor, CO2 sensor, Contact temperature sensor for both air conditioner andthe heater, Window contact and Window handle sensor for ventilation. This is consider as anexample home automation scenario for heating, ventilation, air-conditioning.The Concept of EnOcean Technology is mentioned in [ENOC3] states that Energy harvest-ing wireless switches and sensors for Green-Smart-Wireless. The idea that led to this innova-tive technology is based on a very simple observation: where sensors capture measured val-ues, the energy state constantly changes. When a switch is pressed, the temperature alters orthe luminance level varies. All these operations generate enough energy to transmit wirelesssignals. [Enoc3]
  10. 10. 2.1 EnOcean Technology 10Figure 2.1.2: Energy Harvesting Wireless Sensor Solution from EnOcean Technology. [Enoc3]The basic principle of working of a sensor wireless module is shown in figure 2.1.2. Thisframework is divided into two specific modules, the Wireless Sensor Module and the Wire-less System Module which together combine to build up the Energy harvesting WirelessSensor Solution defined by EnOcean Technology. Wireless Sensor Module :This module consists of five basic technical building blocks which are described as follows: 1) Energy Convertor /Energy Harvesting Devices: This is the process by which energy is derived from external sources (e.g., solar power, thermal energy, wind energy, salinity gradients, and kinetic energy), captured, and stored for small, wireless autonomous devices. 2) Microcontroller: This is used to utilize the embedded functionality behaviour of the wireless sensor module. This includes the processing and controlling of the devices depending upon the information received and also transmitted from the module. 3) Energy Management: This sub-module adds up to the functionality of the wire- less sensor module, it can be used to manage other sensor based devices and Energy Converter/ Energy Harvesting Devices. 4) Sensor: This sensor is a device that will measure a physical quantity and con- vert it into a signal which can be read by the microcontroller for processing and controlling. 5) RF Transceiver: This sub module provides the functionality to send and receive RF (Radio Frequency) Signals.
  11. 11. 2.1 EnOcean Technology 11Figure 2.1.3: Wireless Sensor Module (Block Diagram)The Energy Converter works as a component to convert energy from the nature based onprinciples like piezogenerator, thermocouples, solar cells etc. as mentioned in chapter 2.1.2.These devices acquire the energy from the environment which can be utilized based on theEnOcean Technology e.g. wireless switches working on the principle of piezogenerator.Now, to give an overview of the working is that the wireless switch consists of piezoelectriccrystals or fibers which generate a small voltage whenever they are mechanically deformed.It changes the surface temperature of the piezoelectric crystals and excites the electrons ofthe piezoelectric crystals which eventually generate energy. This Energy can be consumed tosend signals to the microcontroller which processes and controls the signals.The sensor acquires the information from the environment and then sends this information assignals to the microcontroller which eventually processes and controls the information. Forexample, a motion sensor will sense some motion on the base of sound (acoustic sensors),opacity (optical and infrared sensors and video image processors), geomagnetism (magneticsensors, magnetometers), reflection of transmitted energy (infrared laser radar, ultrasonicsensors, and microwave radar sensors), electromagnetic induction (inductive-loop detectors),and vibration (tribo-electric, seismic, and inertia-switch sensors). All these are principles thatdetect motion and then the sensor will send a signal to the microcontroller.After receiving all the signals based on sensors or Energy Converters the microcontroller cantransmit these signals over a transceiver as a RF (Radio Frequency) signal. Wireless system module:This module actually concludes to the module wireless sensor module, so as mentioned ear-lier when the transceiver sends a RF(Radio Frequency) signal the transceiver at the wireless
  12. 12. 2.1 EnOcean Technology 12system end receives this signal and then operates the actuators depending upon the type ofmessage received.Figure 2.1.4: Wireless System ModuleAs, concluding from figure 2.1.3 the wireless system module receives the RF signal asshown in figure 2.1.4 and then after processing, the microcontroller sends the signal to theactuator This module consists of three sub modules which are as follows: 1. Transceiver: The transceiver receives the signal from the sensor module which is processed by the microcontroller. 2. Microcontroller: The microcontroller processes the signals and transmits it to the actuator depending on the type of message (this message is the Telegram Message which will be mentioned in detail later on). The type of message consists of a status field, measured field and also a controlling field which eventually controls the ac- tuator depending upon the message received. 3. Actuator: An actuator is a mechanical device for moving or controlling a mecha- nism or system. It is operated by a source of energy, usually in the form of an elec- tric current. So this actuator can be used to do various kinds of operations. For ex- ample turning light on, controlling heating system, controlling air conditioner.
  13. 13. 2.1 EnOcean Technology 13Figure 2.1.4: The complete abstract-level overview of the wireless Energy Harvesting EnOcean Technology.The complete abstract view after combining the wireless sensor module and the wirelesssystem module can be seen in figure 2.1.4 which shows how Energy converters and Sensorscan be utilized to create an action on the actuator. So concluding with the same idealisticapproach some examples can be viewed. For example any motion sensor can produce anaction on the actuator to make some event like controlling the heating system.Some of the important features of the EnOcean Technology as mentioned in [Enoc3] are asfollows:  A highly optimized automation and controlling solution.  Easy to integrate components, for example Energy converters, energy management & radio modules, system & communication software.  Radio modules without batteries: The required operating energy is typ. 50 μWs per radio telegram only.  Operating energy is generated by pressure, movements, light, temperature, vibration, rotation, etc.  High transmission range: Up to 300 m outdoor up to 30 m indoor.  Minimal emission energy: Less than the spark radiation of a conventional light switch, one million times less a mobile phone.  Reliable signal transmission, suited for systems with hundreds of sensors (since signal transmission time is a thousand of a second only)  Reliable against external disturbances: Repeated radio signal transmission delayed at random, using of regulated frequency ranges approved for pulsed signals only  Prearranged transmitter to receiver assignment: Four billion code numbers are fixed, easy learning procedure (push receiver learn button and activate transmitters)Considering all the aspects of the EnOcean Technology, the most specific feature is the En-ergy Harvesting Concept to control home automation devices.
  14. 14. 2.1 EnOcean Technology 14EnOcean Technology Technical Characteristics as mentioned in [Enoc3] are shown in figure2.1.1, which is as follows:Table 2.1.1: Characteristics of the EnOcean Technology modules.Frequency 868.3 MHz or 315 MHz (depending upon on the location)Transmission power: 6 dBm (antenna input)Receiver sensitivity: -97 dBModulation type: ASKData rate 125 kHzChannel bandwidth 280 kHzRadio telegram 1 ms, variable telegram length (e.g. 53-130 bit incl. 32 Bit sensor ID, 1-4 byte sensor data, checksum)Transmission time 40 ms for three identical radio telegrams, delayed at random2.1.3 EnOcean Communication ArchitectureThe EnOcean Technology builds up its own communication architecture based upon actua-tors. Based on [Enoc4] EnOcean is a patented energy harvesting wireless sensor solutionwhich enables to generate a signal of range from an extremely small amount of energy. Fromjust 50 μWs a standard EnOcean energy harvesting wireless module can easily transmit asignal 300 meters. The secret lies in the signal duration which means that the entire processis started, executed and completed in no more than a thousandth of a second.Figure 2.1.5, shows the network architecture of EnOcean Technology, the bidirectional com-ponents are gateways which communicate over TCP/IP, EIB, KNX, Modbus, these are thestandards for communication in home automation devices. The receivers are actuators whichbasically communicate over RF. The battery less switches are transmitters which also com-municate over RF. A common message protocol is followed which is known as telegrammessage which allows to create any kind of activity on the actuators and sensors.
  15. 15. 2.1 EnOcean Technology 15Figure 2.1.5: EnOcean Wireless Networking System with battery-less nodes. [ENOC4]The EnOcean Technology based network communication architecture is basically dividedinto two areas which are as follows:  Radio Frequency (Access Network)  TCP/IP (Transmission Control Protocol/Internet Protocol), EIB(European Installa- tion Bus), KNX, Modbus(Wired Backbone).The communication architecture of EnOcean Technology can be divided into two areaswhich are as follows: 1) Radio Frequency based wireless communication which can be correlated to the ac- cess network in regard to the conventional network architecture. 2) TCP/IP or any other specific backbone related protocol (e.g. LON, EIB/KNX, Mobus) can be used to build the backbone architecture for the communication.
  16. 16. 2.1 EnOcean Technology 16Figure 2.1.6 EnOcean Technology based Network architectureIn figure 2.1.6, the EnOcean Technolgy communication architecture can be seen. The archi-tecture consists of the following network elements:  Access network: The access network is a RF signal based wireless network which allows sensors and energy harvesting devices to communicate with the Gateway.  Backbone network: The backbone network is based on TCP/IP. The gateway can send information received from the access network to the backbone network. The sending information and receiving information is based over TCP/IP  Sensor: The sensor is network element in the access network and communicates over RF signals.  Gateway: The gateway will operate like a transceiver within the access network based on RF signals.  Energy Harvesting Devices: The transmission of information by these devices is based on RF signals.The Energy harvesting devices and the Sensors transmit information based on RF signals.The backbone architecture is TCP/IP based which is connected to the gateway. This gatewaycan send and receive signals from the access network. However, in the backbone architecturethe gateway can send the information over TCP/IP.Keeping in mind, the transmission at access network is based on RF signals. It becomes veryimportant to analyse the transmission rate of the telegram messages, which is an EnOceanTechnology specified protocol. Figure 2.1.7 shows a graph which measures the transmissionreliability.
  17. 17. 2.1 EnOcean Technology 17Figure 2.1.7: Transmission reliability Graph [Enoc4].In this graph, a comparison of typical radio sensor transmission and the EnOcean technologybased transmission is compared. The number of sender transmitting data increases graduallymaking. Closely analysing the graph, it can be depicted that as the number of senders in-creases, the transmission of typical radio sensor decreases. In the same graph scale, thetransmission of EnOcean technology based sensors is much higher; this makes the possibilityof telegram collision rate to decrease. As mentioned in [Enoc4] transmission reliability isstill better than 99.99% for 100 wireless sensors each transmitting their data once a minute.Considering this information to be accurate, it gives a possibility that a large number EnO-cean wireless sensors and modules can be used in the same building which will transmitreliable telegram messages.2.1.4 EnOcean Technology based GatewayThe EnOcean Technolgy based gateway is one of the important elements in the communica-tion architecture of EnOcean Technology. This allows to interact with the access based net-work devices and to send the information over TCP/IP. In simple words it is a gatewaywhich has the capability to send and receive information over TCP/IP and also operates as atransceiver for the energy harvesting devices and sensors, as mentioned in chapter 2.1.3.Figure 2.1.8 shows the picture of the used BSC-BAP-TX wireless access gateway. Thisgateway consists of a TCM (Transceivers Module) 120 modules, this module consists of thefunctionality of a wireless sensor module and a wireless system module as mentioned inchapter 2.1.2. The TCM-120[Tcmu] module serves the 868 MHz air interface protocol of
  18. 18. 2.1 EnOcean Technology 18EnOcean. It receives all signals of the EnOcean radio transmitters e.g. modules PTM (Push-button Transceiver Module)-100 and makes them available at the serial port. The PTM is awireless push button controller which is a wireless switch and is mentioned in detail in chap-ter 2.1.8.Figure 2.1.8: A picture of the BSC-BAP-TX Gateway.[Bscb]The gateway operates on an embedded module TCM-120. The transceiver module TCM 120of EnOcean enables the implementation of bi-directional RF applications based on the inno-vative EnOcean radio technology. Typical applications are bi-directional EnOcean compati-ble radio interfaces, e.g. to existing system solutions or bus systems. The TCM 120 trans-ceiver module serves the 868 MHz air interface protocol of EnOcean radio technology.[Tcm1]Important features of the BSC-BAP Access Point based on TCM 120 transceiver which aremention in [Bscb] are as follows:  128 actuators and an optional number of transmitters that is compatible with EnO- cean wireless technology per BAP.  It can be integrated in an existing network infrastructure.  PoE(Power over Ethernet) can be used for connection  BSC - BAP uses up to 0.5 Watts of power which makes it a very low power con- sumption device.  EnOcean technology based devices can be integrated to the BSC-BAP. For exam- ple, PTM-200 or PTM-100, Wireless Actuators, Wireless sensors based on EnO- cean Technology.There are some limitations of the gateway which are mentioned in [Bscb] and are ellabo-rateed as follows: 1) The electrical field strength and the magnetic field strength are inversely propor- tional to the square of the distance between the sender and the receiver. This has an affect while transmitting RF signals. 2) Interfaces by materials like metallized foils of thermal insulator, metallized heat- absorbing glass. These materials can reflect electromagnetic waves. A so-called ra-
  19. 19. 2.1 EnOcean Technology 19 dio shadow is built up behind these parts. Some figures related to the amount of penetration of radio signals which can be created are as follows: Table 2.1.3 EnCana RF penetration level in percentage.[Bscb] Material Percentage of Penetration Wood, gypsum, glass uncoated 90 to100% Brick, pressboard 65 to 95% Reinforced concrete 10 to 90% Metal, aluminium pasting 0 to10% Figure 2.1.10, shows a picture of range and penetration being decremented when an iron acts as an obstacle between the transmissions. 2.1.9 Radio path range/-penetration, Reference: As, it is shown on the left side of the figure 2.1.9, that the iron casts a radio shadow between the receiver and the sensor. This is a drawback while implementing the sensor and actuator based home automation environment. On the right side of the figure 2.1.9, the effective range of radio frequency between two receivers. As one is receiving a very good range of radio frequency and the other one is receiving it at a slightly lower level.2.1.5 BSC-BAP-TX Access PointThe industrial name provided to the EnOcean Gateway is BSC-BAP-TX Access Point[Bscb].This gateway operates on 5 ports; all these 5 ports define a specific functionalitydepending upon the different types of functions which can be used. In this section, a detailoverview about the EnOcean Gateway Ports is described. The 5 ports can be utilized on thebases of network programming, specifically client server programming. To mention in detailamong the 5 ports, 2 ports work as a client socket where the remaining 3 work as a serversocket. Following is a list of Ports which is utilized to use the functionality of the EnOceanGateway: 1) 2010: This port is used to configure the IP address of the EnOcean Gateway
  20. 20. 2.1 EnOcean Technology 20 2) 2001: This port is utilized to establish a connection between the Gateway and the Server. 3) 2100: This port is utilized to handle the connection between the gateway and the Server. However, this port can be changed which allows more gateways to connect to the server. 4) 2003: This port is utilized to make sure that the Gateway is ready. 5) 2005: This port is utilized to send a specific message to the gateway. 6) 2002: This port is utilized to close the connection between the gateway and the server.The different types of ports and their functionality are described as follows:  Port 2010 : Setting Server and Gateway IP-addresses This port is used for initial configuration of the gateway IP-address and the server IP-address. This port is used to establish a connection and configure the BSC-BAP Gateway and Server. SETIP#<IP-ADRESS>#<Sub network>#<Server-IP> This command can be used anytime to change the IP-addresses of the gateway and the server.  Port 2001: open connection for the Gateway This port is used to establish the connection between the gateway and the server. It means gateway is trying to connect to the port 2001 of the server in a cyclic way, each 10 seconds.  Ports from 2100: the transfer ports on the Server for receiving the telegrams from the Gateway These ports are to be chosen by user. It can be any port from 2100. The data ex- change between gateway and server. This provides the functionality to receive the telegrams sent from the gateway.  Port 2002: Send control commands to the Gateway This port provides the functionality for server to send controlling commands for disconnecting from gateway and to reset the gateway. >>>>byebye<<<< (String) This string is used to close the connection between the gateway and the Server >>>>>reset<<<<<< (String) This string is used to reset or restart the gateway. This functionality is similar to the hardware reset button on the upper side of the gateway  Port 2003: check the readiness of the Gateway. To ensure that there is no failure in the operation of the gateway, the server should verify the readiness of the gateway in a cyclic way. The user can define the period of cyclic checks. If the gateway is ready, the server receives the message “ready” on port 2003. Normally gateway send “>>>>ready>>>>(String)” message every 10 seconds.
  21. 21. 2.1 EnOcean Technology 21Considering the functionalities of the port, the complete procedure of utilizing the ports isexplained as follows:Initially, port 2001 is opened as a server socket. This allows the gateway to establish a con-nection to the server. The next step is that the server acts as a client and sends a message.This message includes three important parameters: accepting the connection, system Nano-time and a specific port number which is 2100 i.e. the port can be equal to 2100 or more than2100, this allows the gateway to send telegram messages specifically on this port which issend to the gateway by the server. After following this process a TCP connection is estab-lished between the gateway and the server. EnOcean EnOcean Resource Gateway Adaptor EnOcean Gateway Establishing a connection Accepts Connection & sends message containing Port ServerSocket(Port 2001) 2100 and System Nano Time Receive Telegram Messages ServerSocket(Port 2100) Receive READY Status Message ClientSocket(Port 2003) Sends Telegram Messages ClientSocket(Port 2005) Sends RESET Status or BYE Status Message ClientSocket(Port 2002)Figure 2.1.10 shows the MSC between the gateway and the EnOcean Resource AdaptorNow, the gateway is ready to send out telegram messages as string. To make sure that thegateway is ready to send telegram messages another port 2003 is utilized which is opened asa client socket. As this port is initiated a specific ready string is sent to the server, this stringverifies that the gateway is ready to send and receive telegram messages. Figure 2.1.10,shows a MSC between the EnOcean gateway and the EnOcean Resource Adaptor. The EnO-cean Resource Adaptor is based on the JSLEE model which is explained later in the thesis.
  22. 22. 2.1 EnOcean Technology 22After, completing the connection and the ready state, the gateway is ready to receive tele-gram messages from the server. To send a telegram message to the gateway a specific port2005 is used, which is opened as a client. On this port telegram messages are sent whichallow any kind of activity on the EnOcean device depending upon type of telegram message.For closing the connection between the gateway and the server, another port 2002 is used.On this port a specific string >>>>byebye<<<< is sent which closes the connection betweenthe gateway and the server.Table 2.1.2 List of the EnOcean gateway ports and their functionality Port Functionality Type of Socket 2001 Establish Connection, gateway Server Socket can receive a special message. 2100 Special port to receive messages Server Socket from the gateway. 2003 To make sure gateway is ready Client Socket 2005 To send telegram messages Client Socket 2002 To send message for closing Client Socket connection or resetting connec- tion.2.1.6 Wireless ActuatorThe wireless actuator [Elta1] is an impulse switch with integrated functionality to the EnO-cean communication architecture. Some of the important features as mentioned in related tothe devices are mentioned below:  The universal impulse switching relay can be controlled by a conventional 230 V AC control switch.  35 wireless pushbuttons can be assigned to the wireless actuator. The wireless pushbuttons are configured by using the learning functionality of the wireless actua- tor.  Wireless window/door contacts can also be configured to the wireless actuator. In this scenario there can be two possibilities: firstly the window/door is opened this can be facilitated to the wireless actuator by using the normally open (N/O) contact functionality; secondly window/door is closed by using normally closed (N/C) con- tact while the window is closed.  The wireless actuator consists of functionalities which can be configured depending upon the requirements. Following is a table which shows some configuring features of the wireless actuator:
  23. 23. 2.1 EnOcean Technology 23 Table 2.1.3 Configuration mode of the wireless actuator Configuring modes Configuring functionality ER Switching relay ESV Impulse switch. Possibly with off delay + = ESV with push-button permanent light + = ESV with switch-off early warning + = ESV with push-button permanent light and switch-off early warning. LRN Using this configuration field a push button can be made to learn with the wireless actuator. CLR This configuration filed is used to clear old set configuration mode.The following figure 2.1.11 shows the place on the wireless actuator where the configurationrelated to the above mentioned functionalities can be done.Figure 2.1.11: Wireless Actuator[Elta1]The wireless actuator consists of two configuration section:One is to configure the functionality of the wireless actuator depending upon the require-ments as mentioned in table 2.1.3; this section can be seen as the configuring mode place onthe wireless actuator. The other section is the time relay configuration section which allowsthe wireless actuator to modify the time relay of the receiving signals, this makes it possibleto expand the communication architecture if many actuators are located in a home or build-ing.
  24. 24. 2.1 EnOcean Technology 242.1.7 Wireless single-phase energy meterThe wireless single-phase [Elta2] energy meter measures active energy by means of the cur-rent between input and output and transmits the consumption and meter reading over the RFsignal.Figure 2.1.12: Wireless Single Phase Energy Meter [Elta2]Some of the important features of the Wireless Single phase Energy Meter [Elta2] are asfollows:  The wireless energy meter gives a reading only when the power consumption is more than 0.3 watt active power.  Only a one phase conductor with a maximum current up to 16A (Amperes) can be connected.  The rush in current is 20mA.  The reading of the energy consumed is saved to a non-volatile memory and is im- mediately available again after a power failure.  The change in power status by 10 % enables the wireless energy meter to send a telegram message within 20 seconds.  A full telegram comprising meter reading and power status is transmitted after every 10 minutes.  When the power supply is switched on, a teach-in telegram is sent to teach in the as- sociated energy consumption indicator.
  25. 25. 2.1 EnOcean Technology 252.1.8 Wireless Switch/Push-buttonThe wireless switch/push-button as mentioned in [Elta3], operates with in the access net-work. RF signals are used for the transmission of telegram messages. Figure 2.1.13 shows anexample of a single rocker switch which can be used to send telegram messages within theRF signal. The wireless switch is based on the PTM -100. As, mentioned in [Ptms], thismodule is based on the principle of electro-dynamic energy transducer, which sends out RFsignals when the button is pressed and released.Figure 2.1.13: Wireless Switch/Push Button [Elta1]Important features of the wireless push button [Elta3] are as follows:  The Wireless push-buttons with one rocker, one rocker push button means that only one button can be used to evaluate the functionality of transmitting telegram mes- sages over RF signals. It transmits two evaluable signals: press rocker up and press rocker down.  Wireless push-buttons with double rocker can transmit four evaluable signals: press two rockers up or down.2.1.9 Wireless Motion/brightness sensorThe wireless motion sensor [Elta4] operates within the access network of the EnOcean com-munication architecture, this enables the device to send telegram messages over RF signalsto the EnOcean gateway. Figure 2.1.14 shows a figure of the wireless motion sensor.
  26. 26. 2.1 EnOcean Technology 26Figure 2.1.14: Wireless Brightness/ Motion SensorImportant features of the wireless motion sensor [Elta4] are as follows:  The wireless motion sensor transmits telegram messages to the EnOcean wireless access network after every 100 seconds.  The wireless motion sensor transmits two signals instantaneously after detecting motion.  The switch-off signal is sent after the off delay which has a fixed setting of 1 min- ute.  The motion sensor transmits signals with the information of the status every 20 minutes.2.1.10 EnOcean Equipment ProfilesIn this chapter, information with respect the EnOcean Equipments Profiles and the telegrammessages will be provided. The EnOcean Equipment profile is a specification on which tele-gram messages can be created. The telegram message is message stack which is transmittedon RF signals. The EnOcean Equipment Profile provides the information of the telegramstack which is described in this chapter. Based on [Eepv1], the telegram message stack canbe created which can provide functionalities like turning light ON and turning light OFF.Definition: The EnOcean Equipment Profile (EEP) is a unique identifier that describes thefunctionality of an EnOcean device irrespective of its vendor. [Eepv1]During the time of development a new EnOcean Equipment Profile is being released, thisprofile introduces some more functionality like Smart Ack, Remote management (RPC),MSC telegram, Bi-directional profiles (4 BS).New Definition: The ERP specification defines the structure of the entire radio telegram.The user data embedded in this structure is defined by the EEP. [Eepv2]
  27. 27. 2.1 EnOcean Technology 27However, in this chapter the old specification [Eepv1] is being explained as during the reali-zation phase, the old specification [Eepv1] is being used. In chapter 2.1.11, a small descrip-tion about the new functionality and a new radio protocol stack is mentioned.The EEP (EnOcean Equipment Profile) is defined on the bases of EnOcean technology de-fined fields:  ORG: Identifies the EnOcean Messages which allows the communication of the EnOcean devices.  FUNC: This field represents the basic functionality of the data content in the tele- gram message.  TYPE: This field represents type of device in its individual characteristics.In figure 2.1.15, the telegram stack is presented, in this figure it can be seen how the tele-gram stack is organized and which fields are useful for developing an EnOcean message.Figure 2.1.15: Telegram Stack [Tcmu]The Data_Byte field represents the FUNC field of the telegram message that provides thefunctionality of the telegram message. The FUNC field describes the type of activity to becreated. So the functionality to make a light to turn on or off is handled by this field. TheID_BYTE field represents the TYPE field of the telegram message. Figure 2.1.15 elaboratesthe functionality of the telegram stack in detail. The main functionality of the telegram mes-sage stack can be understood by the figure 2.1.16. In this figure basically the complete stackis explained.
  28. 28. 2.1 EnOcean Technology 28Figure 2.1.16: Detail Description of the EnOcean Telegram [Tcmu]Following a detailed description of the Telegram message is provided: 1. SYNC_BYTE: This field of the stack is used for synchronization of received bytes and sent bytes. It consists of two sync bytes which are 8 bits each. [Tcmu] 2. H_SEQ: This field of the stack is the Header Sequence; this field identifies which type of function the telegram message will implement. The length of this field is of 3 bits. [Tcmu]Types of telegram functions: 3. RRT (Received Radio telegram): the function to receive radio data telegram on the BSC-BAP-TX [Bscb] gateway. 4. TRT (Transmit Radio Telegram): This function of the telegram message provides the function to transmit radio data telegram to the BSC-BAP-TX [Bscb] gateway. 5. RMT (Receive Message telegram): This function of the telegram message provides the function to receive telegram messages from the energy harvesting devices. 6. TCT (Transmit Command Telegram): This function of the telegram message pro- vides the function to send command telegram messages which means, the energy devices can be controlled by using this telegram message. 7. LENGTH: This field of the stack provides the information about the number octets following the header octet. This field length is of 5 bits and combines with H_SEQ field to complete 1 Byte of the telegram stack. 8. ORG: This field defines which type of telegram is used within the telegram stack. For TCM-120 module there are 6 types of telegram messages, which are shown in
  29. 29. 2.1 EnOcean Technology 29 figure 2.1.16, in this figure the ORG can be distinguished on the bases of the type of functionality. [Tcmu]Figure 2.1.17: Detail Description of the ORG Field[Tcmu]A new version of the EnOcean Equipement profile is also available, in this specification newfunctionalities have been added to make it KNX association standard. The new specificationmentioned on [eepv2] has the following changes which are as follows:  New 4 BS telegrams  Smart Ack [Enoc6 ]  Remote management (RPC) [Enoc7]  MSC telegram [Eppv2]  Bi-directional profiles (4 BS) [Eppv2]  Introduction of Encryption in the presentation layer[ Enoc8]2.1.11 Standardization of EnOcean Radio ProtocolIn this sub chapter a detail description about the standardization of the EnOcean Radio Pro-tocal is provided. In this chapter the new standard as mentioned in [Enoc8] is explained. Asmentioned in chapter 2.1.10, a new specification is released. The new specification followsthis standard.A standardized set of radio protocol is utilized by the EnOcean technology based devices.This determines the transmission layer of the EnOcean technology based devices. Figure
  30. 30. 2.1 EnOcean Technology 302.1.18, shows a table of the standardized EnOcean Radio Protocol. The transmission layer isdivided into 7 layers which are as follows: 1) Application Layer: At this layer of the EnOcean Standard the Data interpretation with respect to the EnOcean Equipment Profile is utilized. 2) Presentation Layer: This layer of the EnOcean Standard, introduces to some basic functionalities like data encryption, data decryption, encapsulating and decapsulat- ing the retrieve and transmitted data. 3) Session Layer: No functionality of creating a session is utilized in the EnOcean Ra- dio Protocol till yet maybe it can be enhanced for future.Figure 2.1.18 Standardization of EnOcean Radio Protocol [Enoc8] 4) Physical Layer: the Physical layer operates at the RF Signal level which considers functionalities related to bit sampling, carrier frequency, modulation, data rate, Tx power, Rx sensitivity 5) Transport Layer: This layer provides the functionality of remote management, Smart Ack. Smart Ack enables bidirectional communication. The communication is managed by a Controller that responds to the devices telegrams with acknowl- edges, for more information please refer to document. [Enoc8], [Enoc6]
  31. 31. 2.2 Transmission Control Protocol (TCP) 31 6) Network Layer: This layer provides functionality of addressing, networking, rout- ing, switching, and repeating. The routing and repeating of the telegram messages is operated on the bases of the decoded telegram messages. Important decoded tele- gram message fields at the bytes level are utilized. 7) Data Link Layer: This layer provides functionality of decoding and encoding the telegram messages like synchronization of bits, checksum of bits, CRC (cyclic re- dundancy check) for error detection and LBT (Listen Before Back). LBT is a tech- nique used in wireless communications whereby a wireless transmitter or repeater first senses its wireless environment before starting a transmission. The aim is to avoid collisions with other senders. It is an optional feature of the transmitting de- vice. [Enoc8]2.1.12 EnOcean Technology SummaryThe EnOcean Technology is known as a standard for home automation devices which makesit possible for various kinds of actuators and sensors located in the home to communicatewith each other. The main advantage is that the transmitting devices which are based onenergy harvesting technique that means these devices acquire the energy from the environ-ment based on simple concepts of electrical and mechanical engineering. The provision ofthe gateway makes it possible to extend the EnOcean Technology based communicationarchitecture. The above mentioned devices are the important elements of EnOcean Teach-nology. There are many other kinds of home devices performing heating and cooling tech-niques based on sensors and actuators on the same principle.2.2 Transmission Control Protocol (TCP)The TCP [793] is one of the core protocols of the Internet Protocol Suite. This protocol isspecified in RFC -793, which provides all the information about TCP. The concept was firstmentioned by Cerf and Kahn. This protocol came to existence from September 1981 andwas developed by IETF (Internet Engineering Task Force).As, mentioned in [793] TCP is aconnection-oriented, end-to-end reliable protocol designed to fit into a layered hierarchy ofprotocols which support multi-network applications. The TCP provides reliable inter-processcommunication between pairs of processes in host computers attached to distinct but inter-connected computer communication networks. It is intended to provide a reliable process-to-process communication service in a multi network environment. The main functionality isconnection establishment based on three way handshake concept, sequencing number, flowcontrol, after timeouts repetition of a TCP message by transmitter, multiplexing of TCPconnection by ports and sockets, checksum with header and data.
  32. 32. 2.2 Transmission Control Protocol (TCP) 322.2.1 TCP Flow ControlTCP is based on the logical concept of flow control; the flow control is basically based onthe different types of control flags which provide the information of the three way handshake between a server and a client.As, mentioned in [793], TCP provides a means for the receiver to govern the amount of datasent by the sender. This is achieved by returning a "window" with every ACK indicating arange of acceptable sequence numbers beyond the last segment successfully received. Thewindow indicates an allowed number of octets that the sender may transmit before receivingfurther permission.The connection is initiated by a client and then the server sends back an acknowledgement tothe user to establish a connection. After the connection that client sends the datagram packetsto the server. This operation is flowed back and forth between the client user and the server,until the required data is transmitted. In the end to release the TCP connection another pa-rameter is set. There is defined TCP terminology based on the functionality of TCP which isknown as control flags. The communication in TCP is based on control flags which are asfollows: 1. SYN = 1: This value provides the information that the TCP-connection establish- ment is initiated. 2. ACK = 1: This value provides the information of the Acknowledgement of a re- ceived TCP-packet. 3. FIN = 1: This value provides the information that a TCP-connection is release.The above mentioned control flags are the basic principle of communication in TCP, Figure2.2.1 shows an example of the control flags between a client and a server.
  33. 33. 2.2 Transmission Control Protocol (TCP) 33 1. The client sends a SYN packet to establish a connection. 2. The server sends an ACK packet to acknowledge the SYN packet. 3. The client completes the three- way handshake. 4. The client sends the actual re- quest. 5. The client sends a FIN packet to indicate that it is done send- ing. 6. The server acknowledges the request and the FIN. 7. The server sends the reply back to the client. 8. The server sends a FIN packet to indicate that it is also done. 9. The client acknowledges the servers FIN.Figure 2.2.1 Example of TCP Control Flow[Tsac ]2.2.2 TCP StateBased on the logic of the flow control in the TCP, complete state can be seen in table 2.2.1.The handling of the gateway and the application server is based on TCP. The connection isestablished on a specific port and other functionalities are handled on various other portswhich are described in chapter 2.2.1, while developing the network interface between theapplication server and the EnOcean gateway based on [Jain], it becomes essential to analysethe TCP connection between the EnOcean gateway and the Application Server. Based on[793] Following is a list of state: Table 2.2.1 TCP state table State Functionality LISTEN Represents waiting for a connection request from any remote TCP and port. Represents waiting for a matching connection request after having sent a connection SYN-SENT request. Represents waiting for a matching connection request SYN-RECEIVED Represents an open connection, data received can be delivered to the user. The normal ESTABLISHED state for the data transfer phase of the connection.
  34. 34. 2.3 Session Initiation Protocol 34 Represents waiting for a connection termination request from the remote TCP, or an acknowledgment of the connection termination request previously sent. FIN-WAIT-1 Represents waiting for a connection termination request from the remote TCP. FIN-WAIT-2 Represents waiting for a connection termination request from the local user. CLOSE-WAIT Represents waiting for a connection termination request acknowledgment from the CLOSING remote TCP. Represents waiting for an acknowledgment of the connection termination request previ- ously sent to the remote TCP (which includes an acknowledgment of its connection LAST-ACK termination request).The above table gives the information of all the possible states, while the TCP communica-tion is established between a client and a server. During the implementation the TCP com-munication is one of the important protocols to analyse as the EnOcean gateway communica-tion with the Application Server is based on TCP/IP.2.3 Session Initiation ProtocolThe Session Initiation Protocol (SIP) is a signalling protocol used for establishing sessions inan IP network. The first RFC of SIP was 2543 which was published in 1992. After that manyRFC have been created. The most recent RFC is 3261. To design a simpler and more modu-lar way to do voice over IP, SIP was standardized in 1999 by the Internet Engineering TaskForce (IETF). SIP makes it possible to use it for signalling between two user agents. Basedon SIP, two-party sessions that are ordinary telephone calls, multiparty sessions that alloweveryone to hear and speak, and multicast sessions which means one sender, many receiverscan be realized. The session may contain audio, video, or data, the latter being useful formultiplayer real-time games. SIP just handles setup, management, and termination of ses-sions. Other protocols, such as RTP (Real Time Protocol) and RTCP (Real Time Communi-cation Protocol), are used for data transport. SIP is an application-layer protocol and can runover UDP [768] or TCP. SIP is a request-response protocol that closely resembles two otherInternet protocols, Hyper Text Transfer Protocol (HTTP) and Simple Mail Transfer Protocol(SMTP). SIP is compatible with Internet applications.According to RFC 3261, SIP is an application-layer control protocol that can establish, mod-ify, and terminate multimedia sessions (conferences) such as Internet telephony calls. SIPcan also invite participants to already existing sessions, such as multicast conferences. Me-dia can be added to (and removed from) an existing session. SIP transparently supportsname mapping and redirection services, which supports personal mobility.
  35. 35. 2.3 Session Initiation Protocol 35The logic of SIP resides upon the SIP messages which are based on request and responsewhich is basically like HTTP. In the following description of SIP, the types of messages andthere operation are described.SIP Request:SIP requests represent one type of SIP messages. There are many types of SIP messagesdepending upon the type of service or methods required while developing a SIP based logicalservice. The following Table 2.3.1represents all types of SIP requests, short description andthe corresponding RFC, further detailed information on each type of request is mentioned inRFC 3261. Table 2.3.1 Table of SIP request Request Description RFC INVITE When received indicates that client is invited to take part in communication; RFC 3261 when sent – inviting other client to take part in a call session ACK Confirms the receipt of INVTE request. RFC 3261 BYE Terminates the call session, can be sent by both called and calling part. RFC 3261 CANCEL Used for cancelling any pending request. RFC 3261 OPTIOINS Retrieval of server capabilities RFC 3261 REGISTER Send user’s address to the server to register. RFC 3261 PRACK Provisional Acknowledgement. RFC 3262 SUBSCRIBE Subscribes for an event notification from the Notifier. RFC 3265 NOTIFY Notifies the subscriber about the new event.. RFC 3265 PUBLISH Publishes an event to the server. RFC 3903 INFO Send mid-session information that does not modify the session state. Can be RFC 6086 used as well when building the sessions without dialog. MESSAGE Asks the recipient to issue SIP request (call transfer). RFC 3515 REFER Transports instant messages using SIP. RFC 3428
  36. 36. 2.3 Session Initiation Protocol 36 UPDATE Modifies the state of the session without changing the dialog. RFC 3311In the above table mostly the first five requests INVITE, ACK, BYE, CANCEL, OPTIONS,REGISTER based on [3261] are used between a UAC and a UAS. The INFO message pro-vides add on functionality for the UAC, while communicating with the AS.SIP response:SIP responses are the second type of SIP messages, they complement the SIP requests. Thefirst line in a SIP response is called “status line” or “status code”. The responses are dividedaccording to the type of the status code as follows:  Informational  Success  Redirection  Request failure  Server-error  Global failureTable 2.3.2 Table of SIP ResponseResponse Type Functionality RFC1xx: Provisional request received, continuing to process the request; RFC 32612xx: Success action was successfully received, understood, and accepted; RFC 32613xx: Redirection further action needs to be taken in order to complete the request; RFC 32614xx: Client Error request contains bad syntax or cannot be fulfilled at this server; RFC 32615xx: Server Error server failed to fulfill an apparently valid request; RFC 32616xx: Global Failure Request cannot be fulfilled at any server. RFC 3261Table 2.3.2, shows all the necessary response messages which are handled by a proxy server,application server or a media server. The response can further be extended, depending upontheir properties. The “1xx”, only shows the series of provisional response type messagessend out. However, there is a list of messages in the same series which can be referred fromthe specific RFC.
  37. 37. 2.3 Session Initiation Protocol 372.3.1 Network Elements of SIPThere are many network elements based on SIP but they can broadly be divided into SIP useragent and the SIP server. The user agent can be of two types: SIP user agent client (UAC)and the SIP user agent server (UAS).SIP User Agent client: This element initiates request to start a session between the useragent and the application server.SIP User Agent server: This element generates responses to the request made by the UAC.There are several network elements defined in the RFC 3261. Some of the important networkelements are as follows: 1. A proxy server, as mentioned in [3261] "is an intermediary entity that acts as both a server and a client for the purpose of making requests on behalf of other clients. A proxy server primarily plays the role of routing, which means its job is to ensure that a request is sent to another entity "closer" to the targeted user. Proxies are also useful for enforcing policy (for example, making sure a user is allowed to make a call). A proxy interprets, and, if necessary, rewrites specific parts of a request mes- sage before forwarding it." The proxy server is responsible for routing and sending out the request to the specific UAC. 2. A registrar, as mentioned in [3261], “is a server that accepts REGISTER requests and places the information it receives in those requests into the location service for the domain it handles." The UAC can register to this server which identifies the user’s location. 3. A redirect server, as mentioned in [3261] “is a user agent server that generates 3xx responses to re-quests it receives, directing the client to contact an alternate set of URIs. The redirect server allows SIP Proxy Servers to direct SIP session invitations to external domains.” The redirect server is responsible for redirecting any SIP re- quests. The redirection of the request depends upon the “to” header field.
  38. 38. 2.3 Session Initiation Protocol 38Figure 2.3.1 A simple peer to peer SIP call between two UAC [Tsac]There can be many scenarios to explain the concept of a SIP call, in figure 2.3.1 a simple SIPcall is shown in which there are four SIP based network elements, the caller, the callee, theProxy server, and the Location server. Considering that the caller and the callee are regis-tered to a register server. The procedure of the call can be seen by the sequences of thenumber indicated in the figure 2.3.1. So basically, the caller makes a call sends an INVITE tothe Proxy server, the Proxy server looks up in the Location server and checks if the calledSIP URI is located on the server meaning there by the mapping between the permanent SIPURI and the temporary URI is created on the basis on the register server which by the way isnot mentioned in figure 2.3.1. After looking up the SIP URI, the location server sends a replyto the proxy server. The proxy server sends an INVITE to the callee, assuming that the calleeaccepts the call; an OK is send to the Proxy Server. The proxy server sends an OK to thecaller; the caller receives the OK and sends an ACK to the Proxy server. To start the sessionbetween the caller and the callee, the proxy server sends the final ACK. In the end a peer topeer connection is established between the caller and the callee for a SIP based call. Theserver functionality can reside on a single machine which can handle all the back end serviceincluding location, redirection, registration and also proxy server functionality.2.3.2 Back to Back User Agent (B2BUA)A B2BUA is a SIP logic that receives a SIP request, reformulates it, and then sends it out asa new request. Responses to the new request are also reformulated and send back out in theopposite direction. In the realized service example, the application server acts as a back to
  39. 39. 2.3 Session Initiation Protocol 39back user agent which means the application sends out responses and also requests depend-ing upon the behaviour of the service. In the scenario the application server controls the SIPmessages between the user agent and the media server, this behaviour of the applicationserver is like a back to back user agent. Figure 2.3.2 shows a B2BUA, which theoreticallydemonstrates the logic.Figure 2.3.2 Example of a Back to Back User Agent [Sipc]In this example service for both the user agents 1 and 2, the SIP server operates as a B2BUA,which shows that it contains the functionality of UAC and the UAS. When a request is re-ceived by the B2BUA, the B2BUA reformulates the header bodies and then forwards therequest to the other user agent. Similarly, when response is received by the B2BUA, theserver can reformulate the header fields and send it to the necessary UAC.According to RFC-3261, a back-to-back user agent (B2BUA) is a logical entity that receivesa request and processes it as a user agent server (UAS). In order to determine how the re-quest should be answered, it acts as a user agent client (UAC) and generates requests.Unlike a proxy server, it maintains dialog state and must participate in all requests sent onthe dialogs it has established. Since it is a concatenation of a UAC and UAS, no explicitdefinitions are needed for its behaviour.2.3.3 SIP DialogThe SIP dialog is an important concept while implementing the service as mentioned inchapter 4. The dialog is basically between two user agents, or between two servers or be-tween user agent and server.
  40. 40. 2.4 Convedia Media Server 40As mentioned in [3261], a “Dialog is a peer-to-peer relationship between two user agents. Itrepresents a context that facilitates the sequencing of messages between the user agents andproper routing of requests between them. The dialog represents a context in which to inter-pret SIP messages.”In context of SIP, a dialog is created between two user agents. After establishing a session, adialog becomes an important concept in SIP which allows the possibility of interpretingvarious SIP messages during the dialog. Each dialog is identified at each UA by three pa-rameters: Call-ID value, a local tag and a remote tag, bringing all these tags together a dialogID is created which is responsible to identify a specific dialog between two user agents. Dur-ing the realization of the service the following dialogs are created between the followingelements:  UAC (User Agent Client) and AS (Application Server).  AS and MS (Media Server).  UAC and MS.2.4 Convedia Media ServerThe RadiSys Convedia CMS-3000 media server delivers carrier-class media processingcapabilities for enterprise IP telecommunication services. Increased processing power, in-cluding I/O throughput upgrades, delivers significant performance improvement for VoiceXML (Extensible Markup Language) based on IVR and messaging applications, while deliv-ering multi-service versatility for numerous applications including IP PBX, instant videoconferencing, IP contact centres, and unified communication solutions. [Conv]The Convedia media server is a hardware based server which provides variety of media re-lated services like call conferencing, announcement calls etc. It is valuable server for IPbased telecommunication infrastructure which supports in providing media based valueadded services. The main functionality of the media server lies with the MSML (Mediaserver mark up language) [5707], more information about the MSML is mentioned in chapter2.4.1. Basically MSML is a type of XML which supports media functionalities. The func-tionality of the media server can be utilized by using the MSML which stores the requireddata types as XML, which eventually can be accumulated for various kinds of media basedservices. The media server supports many media functionalities which include DTMF( DualTone Multi-Frequency), recording and playback, stream connection which provides intercep-tion support for video and audio, video announcements, IVVR(Interactive Voice and VideoResponse). In the implementation of the EnOcean service DTMF functionality is used whichactually demonstrates the behaviour in respect to the controlling of EnOcean devices.
  41. 41. 2.4 Convedia Media Server 412.4.1 Media Server Mark up LanguageBased on the RFC 5707, The Media Sessions Mark-up Language (MSML) is an XML (Ex-tension Mark-up Language) language used to specify and change the flow of media streamswithin a media server. MSML is designed for manipulating media services offered by themedia server to established media sessions based on SIP [3665]. As mentioned in [5707],MSML specifies how media sessions on the media server interact, and controls and invokesmedia services on the media server. For example, MSML can be used to create conferencesand join sessions into conferences. The MSML is handled by SIP which operates as a signal-ing protocol and creates a session between the media server and a controlling agent. Thesession acts as a control channel which is described in sub-chapter 2.4.1. During this session,the user agent can utilize the functionality of the media server which are mentioned in chap-ter 2.4.MSML can also be used with MOML (Media Objects Markup Language) to interact withindividual users or with groups of conference participants, for example applying IVR opera-tions, called “dialogs,” to sessions or conferences. Using MSML, it is also possible to controladvanced conferencing features on a media server, to modify media while a session is inprogress, and to perform advanced session manipulation such as personalized mixing.MSML transactions are originated by application domain events. These events can be inde-pendent of any media or user interaction. For example, an application may play an an-nouncement to a conference warning that its scheduled completion time is approaching.MSML is designed to be used with other languages. For example, MSML does not set up orteardown sessions. Instead, MSML uses a transport protocol such as SIP for that purpose.[5707].The Media Objects Mark up Language based on [5707] generates a media object which is anendpoint of one or more media streams. It may be a connection that terminates RTP sessionsfrom the network or a resource that transforms or manipulates media. MSML defines fourclasses of media objects. Each class defines the basic properties of how object instances areused within a media server. However, most classes require that the function of specific in-stances be defined by the client, using MSML or other languages such as VoiceXML.
  42. 42. 2.4 Convedia Media Server 42Figure 2.4.1 Example of a MSMLFigure 2.4.1, shows an example of a MSML which is used to utilize the functionalities basedon the Convedia Media Server. The MSML is created on the basis of [Msml]. In this exam-ple the dialogstart target, play id, send target, record destination, send target are the parentelements which consists of substitute child elements to enable the service media functionali-ty.MSML does not directly constrain the media processing language. However, the currentimplementation of MSML on the Convedia Media Server supports only MOML as a mediaprocessing language. While MSML addresses the relationships of media streams (in, forexample, simple and advanced conferencing), MOML is an XML language that addressesthe control and manipulations of media processing operations, such as announcement, IVR,play and record, AST/TTS, fax, and video. Together, MSML and MOML form general-purpose media server control protocol architecture.2.4.2 Media Server Control ChannelThe media server control channel creates a session between the application server and theConvedia Media Server. To access the functionality located on the media server based onMSML, a control channel is to be established which allows the user agent to establish a con-
  43. 43. 2.5 JAIN Service Logic Execution Environment 43nection through the application server. Figure 2.4.2, shows an example of a control channel.The control agent can be an application server, which utilizes the functionality of the MediaServer.2.4.2 Convedia Media Server Control Channel [Msml].The Control channel is a SIP based three way hand shake which creates the session betweenthe control agent and the Media Server. When the control channel is created, SIP based IN-FO messages can be send to the media server which provides the UA to use media functio-nality presiding on the media server. Creating the control channel is a fundamental logic toutilize the functionality of the Convedia Media server. This logic is used during the realiza-tion of the EnOcean Service.2.5 JAIN Service Logic Execution EnvironmentIn this chapter the Java API for Integrating Networks Service Logic Execution Environmentis described. Basically, JSLEE is a fundamental architecture for a service delivery platformwhich has an extremely deep conceptual model. In this chapter the important concepts andlogics with respect to JSLEE is discussed.2.5.1 JAIN (Java API for Integrated Networks)JAIN stands for Java API for Integrated Networks. Based on [Jain3] it is an initiative, andrepresents the community extension to of SJN (Sun Java Networks). It is a JAVA API forproviding next generation telecommunication services. The Development proceeds under theterms of Suns Java Specification Participation Agreement (JSPA). It is endorse as Sun de-veloper Network with an initiative to unify complex wire line, wireless and IP communica-tions interfaces into a set of industry defined Java standards. [Jain2]
  44. 44. 2.5 JAIN Service Logic Execution Environment 44JAIN is supposed to integrate all existing types of networks, like IP networks, cellular, wire-less and PSTN networks. This should be done by means of creating industry standards forexecution environments and interfaces for creating intelligent network services and applica-tions. JAIN has a component-based architecture, which it has inherited from Java Beanstechnology, meaning a robust and flexible environment with module architecture. [Jain2]Java APIs for Integrated Networks (JAIN) is a collection of APIs that are based on Javatechnology and provide access to telephone and data networks. The company Sun Microsys-tems has introduced this extension of the Java platform in 1998 to develop network servicesfaster and easier. [Jain3]2.5.2 Service Delivery PlatformJSLEE (Jain Service Logic Execution Environment), where Jain stands for Java API forIntegrated Network. As mentioned in [Sunj] JSLEE is a component model like EJB, Servletor JSP, and is most similar to EJB. The concept is J2EE technologies but is a specializedcomponent model for event driven applications. The SLEE can be implemented independentof J2EE and used stand-alone without requiring a J2EE. The component model is designedand developed to provide telecommunication service developers to develop much more ro-bust.It is a service delivery platform which provides telecommunication application service de-velopers to implement the service in an event oriented way. The complete architecture de-fines a component model for structuring the application logic of communications applica-tions as a collection of reusable object-oriented components, and for composing these com-ponents into more sophisticated services. Based on [Jain], the SLEE architecture also definesthe contract between these components and the container that will host these components atruntime. The SLEE specification supports the development of highly available and scalabledistributed SLEE specification compliant application servers, but does not mandate any par-ticular implementation strategy.One of the most attractive features of the JSLEE architecture is that the applications may bewritten once, and then deployed on any application server that complies with the SLEEspecification. In addition to the application component model, the SLEE specification alsodefines the management interfaces used to administer the application server and the applica-tion components executing within the application server. The JSLEE architecture provides ahighly adaptive and objects oriented based platform which makes it possible for developersto implement service just like any other server based application but keeping in mind thetelecommunication requirements.
  45. 45. 2.5 JAIN Service Logic Execution Environment 45Figure 2.5.1: JSLEE Architecture [Mmjt]SLEE is a container developed for asynchronous event driven applications. In Figure 2.5.1the basic architecture of the JSLEE architecture can be seen which shows how exactly thearchitecture is embedded. Based on [Mmjt] JSLEE can be divided into three parts which arementioned below:Management: This specific component of the JSLEE architecture provides the developer touse various management entities which includes JMX (Java Management Extension), it is amanagement entity that runs in a Java Virtual Machine (JVM) and acts as the liaison betweenthe MBeans and the management application.Framework: The Framework component consists of the major functionality related to eventrouting, profile specification, alarming facilities and the trace. These functionalities areJSLEE specific.Component Model: This component consists the main building block like the SBB (ServiceBuilding Block), the events are fired by the resource adaptor which are accumulated by theSBB. The lifecycle of the SBB is also a part of this model. So, whenever an event basedobject is generated it follows the lifecycle of the SBB. The formulation of the deploymentunits are also done in this component model. The deployment is done on the bases of a spe-cific format which the JSLEE component model can understand. The Look up for any spe-cific facilities is also carried out in the component model. Figure 2.3.1, shows the componentmodel, at step 1, the RA stack consists the communicating protocol which enables the JSLEto communicate with the external environment. At step 2, the mapping of java objects isdone on the basis of [Jain]. At step 3 the event routing is done which utilizes the developedjava objects. At step 3, the Event router routes out the required events to the tended SBB . At
  46. 46. 2.5 JAIN Service Logic Execution Environment 46step 4, more child SBBs can be integrated to the main SBB. At step 5, the SBB can commu-nicate with RA (Resource Adaptor) Stack and at step 6, the RA Stack sends out an action tothe external environment.Figure 2.5.1: Component model of JSLEE[Mmjt]Resource Adaptor & Resource API: This section of the JSLEE architecture allows theJSLEE to communicate with the external environment. The example of utilizing the resourceadaptor can be seen in figure 2.3.1, where the resource adaptor, RA stack consists of a spe-cific protocol stack to communicate to the external environment. The resource adaptor hasthe property to accumulate all the functionality related to a specific communicating protocolwhich allows the JSLEE to communicate with the external environment, a detail descriptionabout the basic conventional resource adaptor is described in chapter 2.6.1.As mention in [Jain], JSLEE is a platform containing multiple containers developed forbuilding applications for centric networks. SLEE is standardized to meet the needs of devel-opers that build real-time event processing applications.
  47. 47. 2.5 JAIN Service Logic Execution Environment 472.5.3 Service Building Block(SBB)An SBB is a software component that sends and receives events, and implements the execu-tion logic of the system. Figure 2.5.2 shows the example of a SBB operation. There is a rootSBB which basically looks up for events fired by the resource adaptor, the root SBB can firemore events to the child SBB depending upon the service logic. So, SLEE contains service“A”, service “B”, service “C”, the handling of the events is done by specific SBB. To verifythe event and the right SBB on which the event is fired a XML format is used. This formatconfigures the property of the SBB and waits for certain events which are fired by the re-source. The handling of the events can further be done depending if a child SBB is requiredfor the service. Events are used to represent important events that can occur at any time. TheSBB follows a specific configuration which provides the information of the vendor, nameand version. This configuration is followed through the implementation.Figure 2.5.2 Example of SBB(Service Building Block)This description is done in the descriptor files which generate a specific SBB id, this id isused as service identity while implementing the service logic. So, every SBB is bounded toan id which is depended to other child SBBs if events are to be fired to the child SBB. Theconfiguration property provides the binding of the events which are to be routed by the eventrouter, while the service is implemented. The concept of event routing is explained in thenext chapter.
  48. 48. 2.5 JAIN Service Logic Execution Environment 482.5.4 Event, Event RoutingEvents fired by the resource adaptor and the handling of the fired events are logical funda-mental concept in the JLSEE architecture. The handling of the fired event is done by theconcept of event routing. Event can be a kind of logic behavior fired by the resource adaptordepending upon the external resource which is based on a communication protocol. TheEvent router actually routes the event to the SBB which is subscribed to the specific event.As mention in [Uocl], an event represents an event which triggers a process, or may be partof a process. Also includes event information describing the event, such as the source of theevent. In addition, an event can be generated from various sources, such as external resourcesthat are tied to the resource adapter using JSLEE, JSLEE by itself or by the application com-ponents within the JSLEE.Figure 2.5.3: The concept of event and event routing [Mobi3].In figure 2.5.3, the Resource Adaptor fires an event which is handled by the event router.The event router forwards the event to the required SBB. The Events are represented within aJSLEE through event objects that are used to distribute information to the resource adapter orSBBs to exchange information among root SBBs and child SBBs. The transfer of an eventtakes place on an Activity Context. Each event object corresponds to a defined event type.The event router ensures that the events of a given type are forwarded to the SBBs who areinterested in receiving events of such type.The event routing between resources and the JSLEE components and the routing of eventsbetween components, is one of the basic functions of JSLEE. In the JSLEE the event modelis based on publish-subscribe model. Based on [Jain] this model decouples the component
  49. 49. 2.5 JAIN Service Logic Execution Environment 49that generated the event of the consumers of that event by the event-routing mechanism, thedistribution of events, from event to event producer-consumer, takes over. So, basically, theresource adaptor works as a publisher which publishes out events and the event router sub-scribes to the published event.2.5.5 Activity and Activity Context InterfaceThe activity and the activity context interface is an important concept in the JSLEE architec-ture. This makes it possible for the SBB to interact with different kinds activities which areformulated in the JSLEE. As mentioned in [Jain], “An Activity represents a related stream ofevents. These events represent occurrences of significance that have occurred on the entityrepresented by the Activity. From a resource’s perspective, an Activity represents an entitywithin the resource that emits events on state changes within the entity or resource.”The activity is entitled to events which fires out events in the JSLEE and the SBB entity cancapture those events and use that event for the Service Logic. Figure 2.5.5, shows an exam-ple of the activity which fires out events to the SBB entity which can then utilize the activityin the service building logic. The activity is handled by a resource that can be a resourceadaptor which formulates the concept behind the activity depending upon the resource adap-tors functionality.Figure 2.5.4: Example for the Activity in JSLEE [Sunj]The activity context interface is another important concept in the JSLEE architecture. It is aninterface between the SBB entity and the Activity which is handled by the resource domain.Basically the Activity fires out events to the SLEE Domain which can be handled by theSBB over the activity context interface.
  50. 50. 2.5 JAIN Service Logic Execution Environment 50Figure 2.5.5: Example of the Activity Context Interface and the Activity [Sunj]The Activity Context interface can be utilized by many SBBs, various useful objects can bestored in the Activity Context interface to maintain a persistence service. Even, the Activitycan be stored in the Activity Context Interface which allows the SBB to utilize the storedactivity in the activity context interface and then use the activity in the service logic.The activity is a resource oriented logic which is implemented in a resource adaptor and theresource adaptor fires outs event on an activity. On the other hand the SBB can accumulatethe event which is fired by the resource adaptor over the activity context interface. The con-ceptual logic of the Activity and the Activity Context interface allows binding the SBB to aresource adaptor.

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