241-206: Chapter 2 Networking Fundamentalsfivedots.coe.psu.ac.th/~touch/241-206/Chapter2.pdf ·...

transcript

241-206: Chapter 2Networking Fundamentals

touch@coe.psu.ac.th

Wednesday, June 10, 2009

Chapter Outline

• Network Terminology

Chapter Outline

• Bandwidth

Chapter Outline

• Bandwidth

• Networking Models

Network Terminology

Physical Network Topology

Computer Communication Protocol

• data representation

• signaling

• authentication

• error detection

Standard Organization

• IETF, IEEE, ISO for internet communication

• ITU-T for telecommunications and PSTN

• ITU-R for radio communications

• NMEA for marine electronics

• etc.

Proprietary Standards

• AppleTalk

• DECnet

• IPX/SPX

• Server Message Block (SMB) and CIFS

• Systems Network Architecture (SNA)

• Apple Filing Protocol (AFP)

Local Area Network (LAN)

• Operate within a limited geographical area

• Usually required high data rate transmission

• Control the network privately under local administration

• Provide full-time connectivity to local services

• Connect physically adjacent devices

LAN Devices

LAN Devices• Repeater

• HUB

• Bridge

• HUB

• Bridge

• Ethernet Switch

• HUB

• Bridge

• Ethernet Switch

• Router

Wide Area Network (WAN)

• Operate over a large geographical area

• Allow access over serial interfaces operating at lower speeds

• Provide full-time and part-time connectivity

• Connect devices separated over wide, even global areas

WAN Devices

• Router

WAN Devices

• Router

• Modem, DSU/CSU, TA/NT

WAN Devices

• Router

• Modem, DSU/CSU, TA/NT

• Communication Switch

Metropolitan Area Network (MAN)

Storage Area Network (SAN)

Virtual Private Network (VPN)

VPN Technologies

Intranet and Extranet

Bandwidth

Why bandwidth is so important?

• Bandwidth is limited by physics and technology

• Bandwidth is not free

• Bandwidth requirement are growing at a rapid rate

• Bandwidth is critical to network performance

Pipe Analogy for Bandwidth

Highway Analogy for Bandwidth

Units of Bandwidth

Unit of Bandwidth Abbreviation Equivalence

Bits per second bps 1 bps = fundamental unit of bandwidth

Kilobits per second kbps 1 kbps = ~1,000 bps

Megabits per second Mbps 1 Mbps = ~1,000 kbps

Gigabits per second Gbps 1Gbps = ~1,000 Mbps

Terabits per second Tbps 1 Tbps = ~1,000 Gbps

Units of Bandwidth

Maximum Bandwidths and Length Limitations

WAN Services and Bandwidth

Throughput

• Actual measured bandwidth

• throughput <= Digital Bandwidth of a medium

Variables that May Affect Throughput

• PC (client)

• The server

• Other users on the LAN

• Routing within the “Cloud”

• The design (topology) of all networks involved

• Type of data being transferred

• Times of day

Transfer Time Calculation

Audio Analogy of Bandwidth

Networking Models

Analyzing Network in Layers

Network Comparisons

Network Communications

Layer Communications

OSI Model

Benefits of the OSI Model

• Reduces complexity

• Standardizes interfaces

• Facilitates modular engineering

• Ensures interoperate technology

• Accelerates evolution

• Simplifies teaching and learning

Physical Layer

Datalink Layer

Network Layer

Transport Layer

Session Layer

Presentation Layer

Application Layer

Peer-to-Peer Communications

TCP/IP Model

Common TCP/IP Protocols

Comparing TCP/IP with OSI Model

Data Encapsulation

010101010101010101

Data Encapsulation Example

241-206: Chapter 2 Networking Fundamentalsfivedots.coe.psu.ac.th/~touch/241-206/Chapter2.pdf ·...

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