Question

A common protocol stack used by many applications is to use TCP at the transport layer and IP at the network layer. The ICMP protocol is also used to report on problems encountered by IP.

1. The IP protocol provides a service referred to as “best effort”. Describe the services of the IP protocol, and potentially ICMP protocol, with respect to flow control (ensuring the sender does not overwhelm the receiver).
2. Describe the service TCP provides with respect to flow control and explain the mechanisms it uses to overcome the deficiencies of IP.

Answer 1

Ans- ICMP: is an integral part of IP and must be implemented by every Ip. the ICMP report the error in the processing of datagram. there are based on two important point .

1. Error handeling or Feedback messaging.

• TTL Exceed.
• parameter problem.
• source quench.
• source redirect.
• Destination Unreachable.

2. Request and Reply

• Echo request and reply.
• Time stamp request and reply.
• Network mask request and reply.
• Router solicitation.

TCP: Transmission Control Protocol is a set of standardized rules allow the computer to communicate on a network as the internet. it is following important points.

• Reliable.
• end to end .
• Byte stream protocol.
• Connection Oriented.
• mux and demux.

IP- it is define IP address of protocol. which uses IP communication of routing function and internet. tcp and Ip both are allow source and destination.

TCP implement for IP 's deficiencies by providing reliable ,stream- oriented connections that hide most of IP. The protocol refear   most Tcp/Ip protocol are based onTcp , the TCP/IP are twin pillars of TCP/IP. it is used unix operating .

Segment Format- is used 32 bit words and 20byte header.

Source port number- it identifies the port number of sender it is a 16 bit field.

Destination port number- it idetifies the port number of recieving application .it is a 16 bit field.

Sequence Numbers- is a 32 bit field.tcp assign unique sequence number to each byte of data of segment .

TCP header conatins the first byte's sequence number.

Round -Trip Time Estimation- round -trip time estimation is perform parameter of tcp .it is used low packets retransmit.if too high connection can sit idle while the host waits to timeout.