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Reliable User Datagram Protocol

RUDP provides a solution where UDP is too primitive because guaranteed-order packet delivery is desirable, but TCP adds too much overhead. 
In order for RUDP to gain higher Quality of Service, RUDP implements features that are similar to TCP with less overhead.

Implementations:

In order to ensure quality, it extends UDP by means of adding the following features:
  1. Acknowledgment of received packets
  2. Flow control
  3. Re-transmission of lost packets
  4. Over buffering (Faster than real-time streaming)
RUDP is not currently a formal standard, however it was described in an n 1999. It has not been proposed for standardization.

 Working Example:
  1. One way to think about how RUDP types of transport work is to use a basic model where all the data is sent in UDP format, and each missing packet is indexed. 
  2. Once the main body of the transfer is done, the recipient sends the sender the index list and the sender re-transmits only those packets on the list. 
  3. As you can see, because it avoids the re-transmission of any windows of data that have already been sent that immediately follow a missed packet, this simple model is much more efficient. 
  4. However, it couldn't work for live data, and even for archives a protocol must be agreed upon for sending the index. 

Probably because of the "task-specific" nature of RUDP implementations, though, RUDP hasn't become a formal standard.

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Comments

  1. Sharda Borse4 October 2016 at 11:09

    so for missed packets it will follow sr or gbn protocol and only difference is in main packet size?

    ReplyDelete
  2. amitkumarx864 October 2016 at 11:12

    for missed packets it will not follow any of it...it will store the information that which packets got missed.
    And then when whole msg got received it will send the list of missing packets to sender.

    So need of SR or GBN in this scenario.

    ReplyDelete

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