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

Application of satellite communication , Application of Satellite Communica...

Application of Satellite Communication started with the installation and commissioning of STD- “B” Earth Station having 11m diameter antenna in 1982, Initially with to only three

Structure of internet servers address, In a client's software , the structu...

In a client's software , the structure of an Internet server's address keyed is as follows: Where: http refer for the communication protocol to be used www refer for th

Explain routing loop issue in rip protoco, Can you determine routing loop i...

Can you determine routing loop issue in RIP protocol?

INAB-426-, As• New Content (Week 5) o System Integration Implementation P...

As• New Content (Week 5) o System Integration Implementation Plan ? Develop a detailed implementation plan that captures the following (address 4 of these): ? Testing activitie

Networking, discuss the interdependence of workstation hardware with releva...

discuss the interdependence of workstation hardware with relevant software

What are the local network security issues, Q. What are the Local Network S...

Q. What are the Local Network Security Issues? Local Network Security Issues Password Protection - Encrypted username & password Group/Owner ID's - File Permissi

the default settings of ipx delay number, The "ipx delay number" command w...

The "ipx delay number" command will permit an administrator to alter the default settings. Explain the default settings? Ans) For LAN interfaces, one tick; for WAN interfaces, s

Mechanical characteristics of RS232 interface, Q. Mechanical Characteristic...

Q. Mechanical Characteristics of RS232 interface? - 9-pin connector - 9-pin connector is more usually found in IBM-PC but it covers signals for asynchronous serial com

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