This chapter introduces Windows networking terminology and configuration. It describes the Network and Sharing Center interface and how to use the network map to view device connections. It also summarizes the TCP/IP protocol suite including IPv4 addressing and configuration, and provides an overview of the new IPv6 protocol with a larger address space and automatic configuration.

1. MCTS Guide to Configuring
Microsoft Windows Server 2008
Active Directory
Chapter 8: Introduction to Windows
Networking

2. Objectives
• Describe networks using Windows terminology
• Configure and troubleshoot TCP/IP protocols
• Describe IPv6 addressing
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3. Windows Networking Terminology
• Network media
• Network Interface Card (NIC)
• NIC driver
• Hub or switch
• Router
• Network protocol
• Client
• Service
• Network
• Internetwork
• Network connection
• Network discovery
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4. The Network and Sharing Center
• Can create network connections, view the status of
existing connections, and troubleshoot network
problems
• Additionally, you can enable and disable the
discovery of other computers on the network, and
configure folder sharing
• Three sections:
– The network map
– Sharing and Discovery
– Tasks
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5. The Network Map
• The network map displays a graphical view of the
network from your computer’s perspective
• Upon connection to a network, Windows asks you
to select the type of network you are connecting to:
Home, Work, or Public
• Based on this choice, Windows designates your
network as one of the following types:
– Public
– Private
– Domain
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6. The Network Map (cont.)
• Devices that run Windows Server 2003 or Windows
XP can’t be placed on the map, because they lack
the necessary Link Layer Topology Discovery
(LLTD) protocol
• Other reasons that a device can’t be placed:
– A computer running Vista connected to a network designated
as public
– LLTD is disabled
– Network discovery is turned off
– Firewall settings on the computer or network are preventing
Windows from detecting the computer
– The NIC drivers don’t support LLTD
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7. The Network Map (cont.)
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8. The Sharing and Discovery Section
• You can enable and disable the following functions
in the Sharing and Discovery section:
– Network discovery
– File sharing
– Public folder sharing
– Printer sharing
• This section can also display information about
what’s currently being shared on the computer
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9. The Tasks Section
• The Tasks section has links to perform the
following tasks:
– View computers and devices
– Connect to a network
– Set up a connection or network
– Manage network connections
– Diagnose and repair
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10. TCP/IP Operation and Configuration
• TCP/IP is the default network protocol installed on
Windows computers. Windows Server 2008 and
Vista are the first two to have IPv4 and IPv6
installed by default
• TCP/IP is a suite of protocols:
– Domain Name System (DNS)
– Dynamic Host Configuration Protocol (DHCP)
– Transmission Control Protocol (TCP)
– User Datagram Protocol (UDP)
– Internet Protocol version 4 (IPv4)
– Internet Control Message Protocol (ICMP)
– Address Resolution Protocol (ARP)
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11. TCP/IP Communication
• When a user opens a web page, a DNS request is sent to
resolve the website name to an IP address
• Once the client has the IP address of the website, it then
determines whether the address is on the same network or a
different network
• If the client is on the same network, the client requests the
MAC address of the Web server. If not, the client sends the
request for the Web page to a router or default gateway
• Routers then forward the request to other routers, until the
request reaches a router connected to the Web server’s
network
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12. IPv4 Address Configuration
• IP addresses are 32-bit numbers divided into four 8-bit
values called octets, each octet can have a value from 0 to
255
• Subnet masks are also 32-bit numbers, that serve to
determine how many bits are allocated to a network ID, and
how many are allocated to a host ID
• When written in binary, 1’s in the subnet mask that
correspond to bits in the IP address mean the matching bit
locations are part of the network ID
• 192.168.1.0 = 11000000.10101000.00000001.00000000
255.255.255.0 = 11111111.11111111.11111111.00000000
• Above shows 192.168.1 as the network ID, .0 as the host ID
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13. Assigning IP Address Classes
• Three classes of IP addresses can be assigned:
Class A, Class B, or Class C
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14. IP Address Assignment Rules
• Rules for IP address assignment
– Every IP address configuration must have a subnet mask
– All hosts on the same physical network must share the same
network ID in their IP addresses
– All host IDs on the same network must be unique
– You can’t assign an IP address in which all the host ID bits are
binary 0
– You can’t assign an IP address in which all the host ID bits are
binary 1
– Computers assigned different network IDs can communicate
only if a router is present to forward packets
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15. Subnetting
• Default subnet mask for an address class does not always
apply
• Bits can be borrowed from the host ID portion of an address
class in order to create additional “sub-networks”
• Example: 172.31.0.0 subnetted to 255.255.255.0
– Creates 256 new networks, with 254 host IDs
– Rule for number of networks = 2n
– Rule for number of hosts = 2n – 2
• An IP network is referred to as a broadcast domain
• Creating multiple subnets can be beneficial in large
environments to reduce the amount of traffic (broadcast
traffic specifically) computers are exposed to
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16. Configuring Multiple IP Addresses
• Windows OSs allow assigning multiple IP
addresses to a single network connection, via
Advanced TCP/IP settings dialog box
• Multiple IP addresses can be useful in these
situations:
– The computer is hosting a service that must be accessed by
using different addresses
– The computer is connected to a physical network that hosts
multiple IP networks
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17. Configuring the Default Gateway
• A default gateway is almost always used in IP
configurations
• The default gateway can not be in a network ID
outside of the host’s network ID
• Just as you can configure multiple IP addresses,
multiple gateways can be configured
• Windows attempts to select the gateway with the
best metric automatically
• Metric is a value assigned to the gateway based on
the speed of the interface used to access the
gateway
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18. Using Multihomed Servers
• A multihomed server has two or more NICs, each
attached to a different IP network
• Each NIC requires its own IP address for the
network to which it’s connected
• Reasons for this type of configuration:
– A server is accessed by internal clients and external clients
– A server provides resources for computers on multiple subnets
of the network
– A server is configured as a router or VPN server
• Multihomed servers can run into routing issues due
to multiple default gateways being configured
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19. Using the Route Command
• Windows computers maintain a routing table that dictates
where a packet should be sent, based on the packet’s
destination address
• Typing route print displays the routing table
• Results are displayed in five columns:
– Network Destination
– Netmask
– Gateway
– Interface
– Metric
• Route command can be used to change the routing table,
and to fix issues caused by using a multihomed server
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20. Using the Route Command (cont.)
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21. IP Configuration Command-Line Tools
• Other command line tools available to assist with
IP configuration:
– Ping
– Ipconfig
– Arp
– Tracert
– Nslookup
• Additional tools are available, but are generally
used to verify correct IP configuration settings and
connectivity
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22. The Ping Command
• Ping is used to test the connectivity between two
computers, by sending an ICMP Echo Request
packet
• If the destination receives the ICMP Echo Request
and can respond, it’ll reply with an ICMP Echo
Reply packet
– Example: Reply from 192.168.100.201 bytes=32 time=<1ms
TTL=128
• To see the options available for the ping command,
type ping /? at the command prompt
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23. The Ipconfig Command
• Ipconfig is usually used to display a computers IP
address settings, but it can perform other tasks
based on the options given:
– /all
– /release
– /renew
– /displaydns
– /flushdns
– /registerdns
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24. The Arp Command
• The Arp command displays or makes changes to
the Address Resolution Protocol (ARP) cache,
which contains IP address – MAC address pairs
• Can add static ARP entries
• Some options for ARP command:
– -a, -g: displays current ARP entries
– -d: deletes ARP entries
– -s: adds a static ARP entry
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25. The Tracert Command
• Usually called “trace route” because it displays the
route packets take between two computers
• Works by sending out packets with a TTL value
starting at 1 and increases the value until the
destination is reached
• Useful for troubleshooting the routing topology of a
complex network and finding bottlenecks
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26. The Nslookup Command
• Used to test and troubleshoot DNS operation
• Can be used in command mode or interactive
mode
• In command mode, you type “nslookup host” to
query for the host’s address
• In interactive mode, you can simply type host to get
the host’s address
• Typing a question mark at the interactive mode
prompt gives a list of available options
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27. Managing Protocols
• Each network connection in Windows Server 2008 has
protocols and services associated with it
• Services / protocols can be unbound (disabled) or bound
(enabled) to a connection in the connection’s Properties
dialog box, by selecting or deselecting the check box next to
the service or protocol
• List of services / protocols
– Client for Microsoft Networks
– QoS Packet Scheduler
– File and Printer Sharing for Microsoft Networks
– Internet Protocol Version 6 (TCP/IPv6)
– Internet Protocol Version 4 (TCP/IPv4)
– Link-Layer Topology Discovery Mapper I/O Driver
– Link-Layer Topology Discovery Responder
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28. Managing Protocols (cont.)
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29. Network Bindings
• By default, every installed service and protocol is
bound to every network connection
• Protocol bindings can be rearranged by selecting
the protocol to be moved, and then by clicking the
up or down arrows in the Adapters and Bindings
tab
• Network connections are then prioritized in the
order shown under this tab
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30. Network Bindings (cont.)
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31. Network Providers
• A network provider is a software component that
allows Windows applications to connect to
resources on other computers
• Different OSs may require different procedures,
which requires different network providers
• Network providers exist for Windows networks,
virtual networks (VMware), Novell networks, Linux
networks, and more
• Performs actions such as making and breaking
network connections
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32. Network Providers (cont.)
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33. Internet Protocol Version 6
• Previous Windows OSs use a Dual-stack
architecture, meaning that IPv4 and IPv6 use
separate implementations of the protocols in the
TCP/IP suite
• Windows Server 2008 and Vista use dual-IP layer
architecture, which means that the IP protocol is
the only component of the TCP/IP suite that’s
different in IPv6
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34. Internet Protocol Version 6 (cont.)
Dual-stack architecture
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35. Internet Protocol Version 6 (cont.)
Dual-IP layer architecture
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36. IPv6 Overview
• Originally named IPng (IP next generation), IPv6
was created in 1994 by the Internet Engineering
Task Force (IETF)
• IPv6 includes the following improvements
– Large address space
– Hierarchical address space
– Autoconfiguration
– Built-in Quality of Server (QoS) support
– Built-in security
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37. IPv6 Address Structure
• Subnetting as done in IPv4 is no longer applicable
• Uses 128 bits, instead of IPv4’s 32 bits, for an
address
• IPv6 addresses are written as eight 16-bit
hexadecimal numbers separated by colons:
– Fe80:0:0:0:18ff:0024:8e5a:60
– Things to note about IPv6 addresses:
• One or more consecutive 0 values can be written as a double
colon, but only one double colon can exist in an IPv6 address
• Leading 0s are optional
• Addresses that start with fe80 are called link-local
addresses and are self-configuring
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38. The IPv6 Host ID
• Host ID of an IPv6 is typically 64 bits and uses the
interface’s 48 bit MAC address for a large portion
of the address, as well as a 16 bit value of FF-FE
that is inserted after the first 24 bits of the MAC
address
• First two zeros in a MAC address are replaced with
02
• This autoconfigured 64-bit host ID is referred to as
an Extended Unique Identifier (EUI)-64 interface ID
• Windows Server 2008 and Vista don’t use EUI-64
by default
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39. Subnetting with IPv6
• Subnetting will still exist in IPv6, but due to the
large address space available, most address
allocations will have a /48 prefix
• This leaves 80 bits for assigning subnets and host
IDs
• 80 bits allows 16 subnet bits (since the interface ID
requires 64 bits), allowing up to 65,536 subnets
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40. Subnetting with IPv6 (cont.)
Typical IPV6 address structure
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41. Chapter Summary
• The Network and Sharing Center can view the status of
network connections and configure their properties
• The network map is a visual representation of computers
and connecting devices in your network
• TCP/IPv4, the predominant networking protocol in use today,
is actually a suite of protocols and services, such as DNS,
DHCP, TCP, IPv4, ICMP, and ARP, among others
• TCP/IP communication is a multi-step process that often
involves the use of several different protocols in the TCP/IP
suite
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42. Chapter Summary (cont.)
• An IP address is a 32-bit dotted decimal number
divided into four octets. Every IP address must
have a subnet mask to indicate which part of the
address is the network ID and which part is the
host ID. Three IP classes exist: A, B, C
• Subnetting uses a modified subnet mask to divide
a large network into smaller, more manageable
networks
• You can configure multiple IP addresses and
default gateways on a network connection
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43. Chapter Summary (cont.)
• Several command-line tools are available for
checking status and troubleshooting IP
configuration, including Ping, Ipconfig, Arp, Tracert,
and Nslookup
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