TCP/IP Protocol Suite and IP addressing

Overview CCNA 1 - Module 9 (3.1)

• Why the Internet was developed and TCP/IP and the design of the Internet
• The four layers of the TCP/IP model
• Describe the functions of each layer of the TCP/IP model
• The OSI model vz. the TCP/IP model
• The function and structure of IP addresses
• How and why sub- and supernetting. CIDR.
• Public vz. private addressing
• Reserved IP addresses
• Static and dynamic addressing
• Routing

Introduction to TCP/IP

History and future of TCP/IP

• Arpanet
• Vinton Cerf

Application Layer Protocols

• FTP, TFTP, NFS, SMB, CIFS, Rsync
• SMTP, Post Office Protocol, IMAP
• SNMP
• Telnet, Rlogin, SSH
• Usenet, IRC
• Routing protocol
• DNS

Sample chapter in PDF-format from CCNA 4.0

Transport layer

Covered in detail in module 11

• TCP
• UDP

Internet layer

Internet Protocol

• IPv4
  • Address Classes
  • Network address
  • Broadcast address
• IPv6
• Hostname
• /etc/hosts

Network Access

• SLIP
• PPP
• PAP
• Ethernet ( Token Ring, FDDI)
• ATM
• Frame Relay
• SMDS
• ( ARP again)

The OSI model and the TCP/IP model

Also explained in Module 2#Networking_Models

Internet architecture

• "The cloud"
• Abstract physical details from users
• Diversity of application and network access layer techniques
• "Dual homed device"
• Fault tolerance
• Redundant paths (routing)

Internet Addresses

Addressing

IPv4 uses 32 bits. Alternatives to IP:

• NetBIOS
• IPX
• SMB

Decimal and binary conversion

Also explained in Module 1#Network_Math

IPv4 addressess

• Hierarchical
  • Network part
  • Host part

IP address classes

• A-E class (most significant bits pattern, range, subnet mask, usage)
• CIDR

Reserved IP addresses

• The network address (first)
• The broadcast address (last)

Public and private IP addresses

• IANA
• Internet Service Provider (ISP)
• Public addressess are unique
  • 10.0.0.0 - 10.255.255.255
  • 172.16.0.0 - 172.31.255.255
  • 192.168.0.0 - 192.168.255.255

Network Address Translation (NAT)

Introduction to subnetting

• "break a large network up into smaller, more efficient and manageable segments"
• By borrowing host bits.

IPv4 versus IPv6

• 4 octets = 32 bits = 4 billion addresses. Dotted numerical notation.
• 16 octets = 128 bits = 640 sextrillion addresses. Hexadecimal notation, with shortening rules.

Obtaining an IP address

Obtaining an Internet address

MAC addresses are unroutable and only locally significant

Static assignment of an IP address

• Through Windows Control Panel or ipconfig
• Linux:
  • system-config-network
  • ifconfig
  • etc

RARP IP address assignment

Reverse ARP - obsolete. Assigns only IP.

BootP IP address assignment

Bootstrap Protocol - Can assign more info, but is not dynamic.

DHCP IP address management

DHCP at Learn Networking

Problems in address resolution

IP and MAC address must match. Advanced topics: Proxy ARP, Common Address Redundancy Protocol(CARP)

Address Resolution Protocol (ARP)

• ARP table
• ARP request ("who-has")
• Default gateway
• The arp command

Advanced topics:

• Arping
• /proc/net/arp
• /etc/hosts
• /etc/ethers

Extra topics (in addition to CCNA)

• ICMP

Additional resorces (besides Wikipedia)

• An Introduction to TCP/IP at Learn Networking
• The TCP/IP Stack and the OSI Model at Learn Networking
• RFC 1180 - The official tutorial

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