1. Introduction to Networking V.T. Raja, PhD James R. Coakley, PhD BA 572 – Advanced Information Systems

2. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Outline  5-layer Network Model A theoretical framework for our day-to-day interactions on the Internet Protocol stack  Network Design and Topology

3. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Theoretical Framework: 5-layer network model  Application Layer (Layer-5)  Transport Layer  Network Layer  Data Link Layer  Physical Layer (Layer-1)

4. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Five-Layer Network Model Major Functions  Application Layer User interface with application software Example: user types web/e-mail address  Transport Layer Packetizing Breaking large messages into smaller packets at source Reassembling packets at final destination Creates/appends TCP header  Packet #  Source/Destination Port ID

5. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Five-Layer Network Model Major Functions – cont’d  Network Layer: Addressing and Routing. Internet Protocol prepares IP header - contents include: Source/Destination IP Address and Routing Information Addressing DHCP Server (Dynamic Host Control Protocol Server)  Assigns IP addresses to client machines requesting an IP address DNS Server (Domain Name Service Server)  Similar to directory assistance – used for finding destination IP addresses. Routing Routing tables; Routers (Tracert); Routing Protocols

6. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Five-Layer Network Model Major Functions – cont’d  Data Link Layer Media Access Control (Handling message collisions) Error Detection/Error Correction Message Delineation (Identifying beginning and ending of packets – since all computer transmissions go out as 0s and 1s over the physical layer) DL layer appends a DL header and DL Trailer  Physical Layer (Layer-1) Transmission of data

7. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Five-Layer Network Model Protocols and Addresses  HTTP (Hyper Text Transfer Protocol) Operates at the Application Layer Example of an application layer address: www.bus.oregonstate.edu www.bus.oregonstate.edu  TCP (Transmission Control Protocol) Operates at the Transport Layer Example of a transport layer default port address/port ID: 80 (Web) 25 (E-mail)

8. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Five-Layer Network Model Protocols and Addresses – cont’d  IP (Internet Protocol) Operates at the Network Layer. Example of an IP address: 128.192.64.224  Ethernet operates at the data link layer. Example of a DLL address: 00-B0-D0-B4-54-13

9. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Layer 1 - Physical Layer  Wired Media/Wireless Media: Examples Twisted pair; Coaxial; Fiber Optic Cables Wireless Wireless Access Points Microwave (radio) towers Cellular network towers Satellites (GEOS/MEOS/LEOS) http://www.orbitaldebris.jsc.nasa.gov/index.html

10. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Some Network Topologies  Physical versus logical topology  Star topology  Mesh topology  Bus topology  Ring topology  Physical versus logical topology

11. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems

12. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems

13. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Ethernet vs. Token Ring Local Area Network  LAN Protocols Ethernet: Bus with CSMA/CD Carrier Sense Multiple Access/Collision Detection Token Ring FDDI Fiber Distributed Data Interface Token Ring on fiber Fast Ethernet (100 mbps) Gigabit Ethernet

14. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems

15. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems

16. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems FDDI

17. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems FDDI (Continued)

18. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Network Design How to support full connectivity?  Design the most economic internetwork between “end-user nodes” and an existing WAN Usernode WAN

19. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Network Design Find an economic internetworking solution Usernode A direct connection to a WAN backbone node Usernode Connection via multiplexers

20. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Some Network Design Issues Major Cost Components  Acquisition and installation costs of a MUX  Cost of high bandwidth link between MUX and WAN (Internet)  Cost of low bandwidth link between end-user node and MUX

21. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Network Design Management How to design a feasible and economical internetwork?  Find an optimal number of MUXs to interconnect all given user nodes to some existing WAN such that... All user nodes are connected User communication requirements are satisfied Capacity constraints on each MUX is not violated Total internetworking costs are minimized Topology issues are considered

22. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Example 1

23. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Example 2

24. V.T. Raja & James R. CoakleyBA 572 – Advanced Information Systems Example 3