This document discusses networking and the Internet. It covers network classifications based on size (LAN, MAN, WAN) and ownership (open, closed). It describes common network topologies like token ring and CSMA/CD. It also discusses how networks can be combined using repeaters, bridges, switches and routers. The document then covers Internet architecture, addressing using IP addresses and domain names, and traditional Internet applications like email, FTP, and the World Wide Web. It provides details on HTML, URLs, and the components of a typical web page.

1. NETWORKING AND THE INTERNET
CS160

2. NETWORK CLASSIFICATIONS
Networking and the Internet

3. NETWORK CLASSIFICATIONS
 Size
 Local Area Network (LAN)
 Metropolitan Area Network (MAN)
 Wide Area Network (WAN)
 Intellectual Property
 Open
 Closed

4. TOPOLOGIES

5. PROTOCOLS
 Token Ring
 Messages passed in one direction
 Each message ends back at original sender

6. PROTOCOLS (CONTINUED)
 Carrier Sense, Multiple Access with Collision
Detection (CSMA/CD)
 Message sent across common bus
 Only intended recipient reads
 On collision, each sender waits before re-sending

7. COMBINING NETWORKS
 Repeater
 Physically connects
two networks
 Passes all traffic
 May amplify signals
to compensate for
increased length
 Bridge
 Passes only
messages for
machines on a given
segment

8. COMBINING NETWORKS (CONTINUED)
 Switch
 Connects two or
more segments
 Routes messages
only to segment
where recipient is
found
 When using
repeaters, bridges,
or switches the result
is one large, homo-
geneous network

9. COMBINING NETWORKS (CONTINUED)
 Router
 Connects two or
more networks with
dissimilar topologies
 Builds networks of
networks called
internets

10. INTERPROCESS COMMUNICATION
 Client-server
 One server, many
clients
 Server must execute
continuously
 Client initiates
communication

11. INTERPROCESS COMMUNICATION (CONTINUED)
 Peer-to-peer (P2P)
 Two processes
communicating as
equals
 Peer processes can
be short-lived

12. THE INTERNET
Networking and the Internet

13. THE INTERNET
 Proper noun
 Originated in Defense Advanced Research
Projects Agency (DARPA) in 1960’s
 Shifted from government to academia to
commercial

14. INTERNET ARCHITECTURE
 Domain: portion of the
Internet that network
or internet controlled
by a single authority
 Connected to the rest
of the Internet by a
router called a gateway
 Internet Corporation
for Assigned Names &
Numbers (ICANN):
Oversees the
registration of domains

15. STRATEGIES FOR CONNECTING TO THE
INTERNET
 Internet Service Provider (ISP): Provides
connectivity to the Internet
 Popular means of connecting:
 Traditional telephone (dial up connection)
 Cable connections
 DSL
 Wireless
 Satelite

16. INTERNET ADDRESSING: IP ADDRESSES
 Every computer on the Internet is assigned an
Internet Protocol (IP) Address
 IPv4
 32-bits (4 bytes)
 232 = 4,294,967,296 unique addresses
 “Dotted quads” xxx.xxx.xxx.xxx

17. INTERNET ADDRESSING : IP ADDRESSES
(CONTINUED)
 IPv6
 128-bits (7 bytes)
 2128 = 3.4 × 1038
 5 × 1028 addresses for each of the 6.5 billion people
alive today
 252 addresses for each star in the known universe
 10 billion billion billion times as many addresses as IPv4

18. INTERNET ADDRESSING: HOST NAMES
 Mnemonic address made up of two parts:
 Domain name
 Assigned by a registrar
 Example: linnbenton.edu
 Top level domain: Classification of domain owner
 By usage – Example: .edu= education
 By country – Example: .co.uk = England
 Subdomains and individual host names
 Assigned by domain owner
 Example: ml.linnbenton.edu
 Translation between mnemonic addresses and
IP addresses handled by name servers

19. TRADITIONAL INTERNET APPLICATIONS
 World Wide Web (WWW)
 Electronic mail
(E-mail)
 File transfer protocol
(FTP)
 Instant messaging (IM)
 VOIP
 Internet relay chat (IRC)
 Telnet
 Secure Shell (SSH)
 Newsgroups
 Archie
 Early index of files
available on FTP sites
 Gopher
 Hierarchical menu-
based system for
document retrieval
(WWW-like)
 Jughead
 Search engine for
Gopher
 Veronica
 Another search engine
for gopher

20. THE WORLD WIDE WEB
Networking and the Internet

21. THE WORLD WIDE WEB
 Hypertext and HTTP
 Hypertext markup language (HTML)
 Hypertext transfer protocol (HTTP)
 Browser gets documents from Web server
 Web page
 Documents identified by URLs
 Uniform resource locator
 World Wide Web Consortium (W3C)
 Standards body

22. A TYPICAL URL

23. HTML
 Set of tags used to identify elements of a web
page
 Designed to be very simple to learn and use
 <p>…</p>
 <h1>…</h1>
 <img src=“foo.jpg />
 <a href=“http://www.linnbenton.edu” />

24. SAMPLE WEB PAGE