Difference between Go-Back-N and Selective Repeat Protocol

By Jaxson

Main Difference

The main difference between these two types is that Go-Back-N protocol sends down different sequence values without getting any confirmation. On the other hand, Selective Repeat Protocol gives the option of canceling and permitting.

Comparison Chart

Basis of DistinctionGo-Back-N ProtocolSelective Repeat Protocol
DefinitionPasses the signal without any permission or authority from the original transmission source.Passes the signal to the user who has the option of giving the permission or revoking it.
ErrorA lot of space is wasted since the failure rates stay high and less information moves from the sender.Less bandwidth is wasted as the error rates are small between the transmitter and the receiver.
SortingNo requirement of sorting different messages.Can sort out all the messages

Go-Back-N Protocol

It is different from other formats as it does not require any authentication when the data moves between the system, where the receiver will only take the next value waiting in line and not everything coming its way. In this manner, the latest message becomes available for the user, but some of the previous information disappears. It also does not mean that the most recent word has the utmost importance. This mode of communication has become redundant for several reasons such as taking a lot of time to complete the cycle and reading all the sequence numbers.  This interaction is initiated between two computers, where people want to send messages to each other. It may be for business or personal usage but for such as case the medium that carries the information between two devices has a protocol that helps it to work. The user asks for the data to move from their computers to the other, and similarly, they have to ask for the data to become visible on their devices. For this purpose, different commands have been used such as DatReq and dating. The usage is simple where the information displays only as many times as suggested, gets a value along with the sign, and then the reader has the screen that shows several values, and it is up to them to decide which command to prompt. Once the value reaches the maximum, then it comes down to the initial value and therefore starts the cycle again.

Selective Repeat Protocol

Here, both the transmitter and receiver exist that help with the fast communication between the users. What makes the system efficiency is the devices that have speedy replies. Hence selective repeat protocol has become the modern mode of protocol that currently rules our devices. Just like other sequences, different commands have been used such as DatReq and DatInd that help with the reading and the sending of information respectively. The transmitter sends a number, and that only shows the value but not the data, this action helps with reading the relevant information that the reader requires. That said, a limit still exists on the number of messages that a person sends to the other and once the maximum value breaches, the cycle starts again with the new messages. It is up to the person using the devices to decide which posts they want to read and which they want to ignore. The sender also gets notified with what the other person does and therefore keeps track of all the activities. The window starts from zero and reaches 7 for most cases before it refreshes. Buffer for each value makes sure individuals lose no data during this process.

Key Differences

  • A lot of space is wasted during Go Back N protocol since the error rates stay high and the sender sends less. Less bandwidth is consumed during Selective Repeat Protocol as the error rates are small between the transmitter and the receiver.
  • The implementation of selective repeat protocol becomes more complicated as different values come into contention. On the other hand, application of Go Back N protocol is more straightforward since no such activity takes place.
  • No requirement of sorting different messages exists within the Go Back N protocol whereas the receiver can sort out all the notes because it has to maintain the procedure that we follow, in selective repeat protocol.
  • The most used protocol that exists within devices is still the Go Back N protocol even though it is old and takes more time. On the other hand, selective repeat protocol makes complex implementation therefore only stays relevant for analytical purposes.

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