9-1 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Principles of Computer ArchitectureMiles Murdocca and Vincent Heuring

Chapter 9: Communication

9-2 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Chapter Contents9.1 Modems9.2 Transmission Media9.3 Network Architecture: Local Area Networks9.4 Communication Errors and Error Correcting Codes9.5 Network Architecture: The Internet9.6 Case Study: Asynchronous Transfer Mode

9-3 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Modem Communication• Communication over a telephone line with modems:

9-4 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Modulation Schemes• Three common forms of modulation:

9-5 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Pulse Code Modulation• Conversion of an analog signal into a PCM binary sequence:

9-6 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Ideal vs. Transmitted Waves

9-7 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Transmission Media

• Transmisson media. (a) Two-wire open lines; (b) twisted-pair lines; (c) coaxial cable; (d) optical fiber; (e)satellites.

9-8 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

The Seven Layers of the OSI Model

9-9 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

A Few Network Topologies• (a) Bus; (b) ring; and (c) star network topologies.

9-10 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Parity• Even parity bits are assigned to a few ASCII characters:

9-11 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Check Bits• Check bits for a single error correcting ASCII code:

9-12 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

SEC coded ‘a’• Format for a single error correcting ASCII code:

9-13 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

SEC Coded ‘d’• Parity computation for an ASCII character in an SEC code:

9-14 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

3-Bit SEC Hypercube• Hamming distance relationships among three-bit codewords.

Valid codewords are 000 and 111. The remaining codewords represent errors.

9-15 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

LRC and VRC Checking• Combined LRC and VRC checking. Checksum bits form even

parity for each column.

9-16 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Cyclic Redundancy Checking

9-17 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Internet Protocol Stack• Layering in the TCP/IP protocol suite:

9-18 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

IPv4 Address Classes

9-19 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Encapsulation• Encapsulation in the TCP/IP protocol suite:

9-20 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Hub vs. Router vs.

Switch

• Configurations shown for (a) a hub; (b) a router; and (c) a switch.

9-21 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Self-Routing Switch• A 44 self-routing switch based on the bubblesort algorithm:

9-22 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

TDM vs. ATM• (a) Time division multiplexing vs. (b) asynchronous transfer mode.

9-23 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Format of an ATM Packet• Format of an ATM packet. (a) User-to-network interface (UNI) format; and (b) network-to-network interface (NNI)

format.

9-24 Chapter 9 - Communication

Department of Information Technology, Radford University ITEC 352 Computer Organization

Simple ATM Network