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Introduction to TCP/IP

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Agenda

What Is TCP/IP? IP Addressing

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What Is TCP/IP?

A suite of protocols Rules that dictate how packets

of information are sent across multiple networks

Addressing Error checking

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IP

Internet Protocol (IP) Determines where packets are routed based on their destination addresses

Breaks packets into smaller packets and reassembles them

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TCP/IP Applications

Application layer File Transfer Protocol (FTP) Remote Login (Telnet) E-mail (SMTP)

Transport layer Transport Control Protocol (TCP) User Datagram Protocol (UDP)

Network layer Internet Protocol (IP)

Data link & physical layer LAN Ethernet, Token Ring, FDDI, etc. WAN Serial lines, Frame Relay, X.25, etc.

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TCP/IP Transport Layer

21 FTP—File Transfer Protocol23 Telnet25 SMTP—Simple Mail Transfer Protocol37 Time69 TFTP—Trivial File Transfer Protocol79 Finger103 X400161 SNMP—Simple Network Management Protocol162 SNMPTRAP

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TCP Transmission Control Protocol

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UDP User Datagram Protocol

• Unreliable

• Fast

• Assumes application will retransmit on error

• Often used in diskless workstations

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ICMP Ping

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IPv4 Addressing

• 32-bit addresses

• Commonly expressed in dotted decimal format (e.g., 192.168.10.12)

• Each “dotted decimal” is commonlycalled an octet (8 bits)

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IP Addressing—Three Classes

• Class A: NET.HOST.HOST.HOST

• Class B: NET.NET.HOST.HOST

• Class C: NET.NET.NET.HOST

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IP Addressing—Class A

• 10.222.135.17

• Network # 10

• Host # 222.135.17

• Range of class A network IDs: 1–126

• Number of available hosts: 16,777,214

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IP Addressing—Class B

• 128.128.141.245

• Network # 128.128

• Host # 141.245

• Range of class B network IDs: 128.1–191.254

• Number of available hosts: 65,534

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IP Addressing—Class C

• 192.150.12.1

• Network # 192.150.12

• Host # 1

• Range of class C network IDs: 192.0.1–223.255.254

• Number of available hosts: 254

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IP Network Address Classes

0000000001111111

10111111

1111111111011111

00000000 00000000

11111111

11111111 00000000 00000000

00000000

# Networks

126

16,384

2,097,152

# Hosts

254

65,534

16,777,214

Class

A

B

C

Class A 35.0.0.0

Class B 128.5.0.0

Class C 132.33.33.0Network Address Space

Host Address Space

Example

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IP Subnetting

• Subnets allow routing by ranges

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IP Subnet Mask

Given:

Address = 131.108.2.160

Subnet Mask = 255.255.255.0

Subnet = 131.108.2.0

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IP Address Assignment

• ISPs assign addresses to customers

• IANA assigns addresses to ISPs

• CIDR block: bundle of addresses

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Summary

TCP/IP is a suite of protocols TCP/IP defines communications

between computers on the Internet IP determines where packets are

routed based on their destination address

TCP ensures packets arrive correctly at their destination address