TCP – Transmission Control Protocol

• Connection oriented
• Sequenced packets
• Acknowledgement is sent back for received packets
• If no acknowledgement then packet is resent
• Packets are re-sequenced
• Manageable data flow is maintained

Note: TCP and UDP use dynamic port numbers greater than 1023

UDP

• Best effort
• Doesn’t care about sequence order
• Connectionless
• Less overhead and faster than TCP

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Internet Layer Protocols

IP – Internet Protocol

• All hosts on a network have an IP address
• Each data packet is assigned the IP address of the sender and the receiver
• It provides an “unreliable datagram” services
• Provides:
  • No guarantees that the packet will be delivered
  • No guarantee that the packet will be delivered only once
  • No guarantee that it will be delivered in the order in which it was sent

ARP – Address Resolution Protocol

• Use the IP Address to get the MAC address
• MAC Address is 48 bit
• IP address is 32 bit
• Only broadcast to network first time, otherwise stores IP and MAC info in table

RARP – Reverse Address Resolution Protocol

• Use the MAC address to get the IP address
• RARP Server tells diskless machines’ IP address

ICMP – Internet Control Message Protocol

• Management Protocol and messaging service provider for IP
• Sends messages between network devices regarding the health of the network
• Ping is ICMP packet
• Ping checks if a host is up and operational

Note: TCP/IP does not define physical standards it uses existing ones

Other TCP/IP Protocols

Telnet

• Terminal Emulation
• No File Transfer

FTP

• File Transfer Protocol
• Can not execute files

TFTP

• Trivial FTP
• No directory browsing capabilities, no authentication
• Can only send and receive files
• UDP-base file transfer program that provides no security

NFS – Network File Sharing

SMTP – Delivers e-mails

X-Windows – For writing graphical interface applications

SNMP

• Simple Network Management Protocol
• Provides for the collection of network information by polling the devices on the network from a management station
• Sends SNMP traps (notification) to  MIBS – Management Information Bases

Bootstrap Protocol (BootP)

• Diskless bootup
• BootP server hears the request and looks up the client’s MAC address in its BootP file
• Internet Layer Protocol