Time out - transport layer, Computer Networking

Assignment Help:

Time  out

Timers  are used to protect  against  lost packet. Each  packet  must have its own logical  timers since  only  a single  packet  will be retransmitted  after timeout. A single  hardware timer can be used to mimic  the function of  multiple logical  timers.

The SR receiver  will  acknowledge  a correctly received packet whether or not it is  in order. Out of order packets  are buffered  until any missing packets ( that  is packets with lower  sequence numbers) are received. The  various actions  taken by the SR receiver.

Packet  with  sequence  number in ( rev base re base + N- 1) is correctly received. In  this case  the received packet falls within the  receiver window  and a selective ACK  packet  is returned  to the  sender.

If  the packet was not  previously  received it  is buffered. If this  packet  has a sequence number  equal to the base of the  window  then this  packet  and any  previously  buffered  and consecutively numbered packets are delivered to the receiver. The  receiver window is them moved  forward  by the number of packets  delivered to the receiver as in figure when a packet  with a  sequence number of 2 is  received  then packets 3, 4 and 5 can  be delivered to the receiver.

Packet with  sequence  number in  ( rev base n rev base-1)  is received. In  this case an ACK  must be  generated this is the packet  which  the receiver has previously  acknowledge.

Otherwise ignores the  packets.

To understand  the functions of SR protocols  lets  take an example  of a window  size of  four packets. The sender  can sends  packets 0 to 3. If  first  packet pkt 0 is  lost  and pkt 1 , 2   and 3 are received by the  receiver instead of discarding these  packets  the receiver  buffers  the packets  and send  the ACK  for the  packets  respectively. After the  time out  of pkt 0 the sender  can retransmit this  lost  packet  pkt 0 if  the receiver receives the lost  packet  pkt 0  then the  receiver deliver all the  packets  which  was kept  buffered  by the  receiver previously.


Related Discussions:- Time out - transport layer

Explain the power of semantic web languages, What is the Power Of Semantic ...

What is the Power Of Semantic Web Languages? Ans) The major power of Semantic Web languages is that anyone can create one, simply by publishing some RDF that defines a set of

Determine how many bits are used for the page number, 1.  A virtual memory ...

1.  A virtual memory system has a virtual address space of 4 Gigabytes and a page size of 8 Kilobytes.  Each page table entry occupies 4 bytes.   a)  How many bits remain unchanged

Computer nework critira, what is compurter network and types, topology, com...

what is compurter network and types, topology, communication media

Describe the architecture of the tcp/ip protocol suite, Problem 1 Descr...

Problem 1 Describe the architecture of the TCP/IP protocol suite Problem 2 Describe the principle of operation of REXEC protocol Problem 3 Describe the concept

What is a web server in client server environment, This new model of Client...

This new model of Client/Server having of thin, portable, "universal" clients that talks to superfast servers. In the simple form, a web server returns documents when clients ask f

Mention and explain 16 bit, Mention and explain 16 bit, basic programmable ...

Mention and explain 16 bit, basic programmable registers in 8086 operated in real mode?

Selective repeat ARQ, Selective Repeat ARQ - Processing at the receive...

Selective Repeat ARQ - Processing at the receiver additionally complex - The window size is reduced to 2(m-1) (2m/2 at most) - Both the transmitter as well as the receiv

network consultant, Network Consultant, My name is Jason Long. I am th...

Network Consultant, My name is Jason Long. I am the CEO of IL Corporation. IL is an investment firm that performs financial services to many organizations. We currently have a

Error detection-general, Q. Error Detection-General? Sender transmi...

Q. Error Detection-General? Sender transmits every data unit twice Receiver performs bit-by-bit comparison between those two versions of data. Any mismatch would

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd