Minimized Congestion: The protocol reduces network congestion by retransmitting only necessary frames, leading to smoother data flow. Faster Recovery: Selective Repeat allows individual damaged or lost frames to be retransmitted, enabling quicker recovery than stopping the entire transmission.
There are two types of sliding window protocol Go-Back-N (GBN), and Selective Repeat (SR). In Go-Back-N, the sender can send multiple data packets without waiting for an acknowledgement for each one. However, it can only send a certain number of packets (this is called the “window size”).
Selective Repeat Protocol (SRP) is a type of error control protocol we use in computer networks to ensure the reliable delivery of data packets. Additionally, we use it in conjunction with the Transmission Control Protocol (TCP) to ensure that the receiver receives data transmitted over the network without errors.
In Go-Back-N Protocol, if the sent frame are find suspected then all the frames are re-transmitted from the lost packet to the last packet transmitted. In selective Repeat protocol, only those frames are re-transmitted which are found suspected. Sender window size of Go-Back-N Protocol is N.
With the cumulative acknowledgment scheme, multiple dropped segments generally cause TCP to lose its ACK-based clock, reducing overall throughput. Selective Acknowledgment (SACK) is a strategy which corrects this behavior in the face of multiple dropped segments.
In Selective Repeat ARQ, the size of the sender and receiver window must be at most one- half of 2m.
In the Stop and Wait protocol, the transmission type is Half duplex. In the Go-Back-N protocol, the transmission type is full duplex. In the Selective Repeat protocol, the transmission type is full duplex.
Selectivity (α) is used to define the ratio of retention times of two sequentially eluting analytes and is a descriptor for the distance between them. Efficiency (N) is used to define the width of each peak and is primarily determined by particle size, quality of the pack and morphology of packing material.
In networking, a protocol is a set of rules for formatting and processing data. Network protocols are like a common language for computers. The computers within a network may use vastly different software and hardware; however, the use of protocols enables them to communicate with each other regardless.
The syntax is extremely small and easy to learn. Because its core resembles that of C/C++, experienced programmers can pick up the basics fast. Although it lacks the functionality of other programming languages, its scope has been deliberately limited to keep it simple.
Go-Back-N is an automatic repeat request (ARQ) protocol used in data communication to ensure reliable data transmission over an unreliable channel, often employed in scenarios like point-to-point communication using protocols like TCP. Go-Back-N is one of the two primary ARQ protocols, the other being Selective Repeat.
Advantages of ARQ are the simple equipment require, needing only a small amount of redundancy, and higher bit rate. The defects of ARQ are error control need a duplex channel, and it does not apply for a simplex channel and unreliable channel.
Advantages of the Protocol
The protocol applies the buffer method, so memory is needed on the sender and receiver sides. It retransmits only the data frames damaged during transmission in the network channel. Need less retransmission, which increases the efficiency and uses moderate bandwidth requirements.
In particular, if no packets are damaged, selective repeat and Go Back N perform equally well. If W is large enough, the sender will never pause so the efficiency of the protocol will be 100% (ignoring the fact that transmitting error checking codes and sequence numbers wastes some transmission capacity).
Half-duplex requires switching between a sending and receiving mode. Half-duplex and full-duplex are two common methods of transmitting data. Half-duplex is when data can only go in one direction at a time. Full-duplex is when data can flow in both directions at the same time.
In selective repeat ARQ, the receive window size is typically set to half the range of sequence numbers. The reason for this is to ensure that there is enough buffer space to handle out-of-order packets and retransmissions. Therefore, the maximum size of the receive window would be 32/2 = 16 packets.
A good rule of thumb is to compare window and floor areas. For a well-lit room, the amount of glazing should not be less than 20% of the floor area of the room it serves. Less than this and you are likely to be using electric lights to make the spaces bright enough to enjoy, which incurs unnecessary energy use.
If a frame from the sender does not reach the receiver, the sender continues to send subsequent frames until it has emptied its window. The receiver continues to fill its receiving window with the subsequent frames, replying each time with an ACK containing the sequence number of the earliest missing frame.
If the size of the window is greater than half the sequence number space, then if an ACK is lost, the sender may send new packets that the receiver believes are retransmissions. Sender can transmit new packets as long as their number is with W of all unACKed packets.
Acknowledgments are cumulative. Whenever a packet arrives, the receiver sends an acknowledgment containing the number of the last packet (actally byte) that was received “in order”. That is, if the sender sees Ack 12, it knows that segments 1-12 all got through Ok.
Selective exposure occurs when individuals seek out information that supports their pre-existing beliefs, while selective retention is the tendency to only remember information that is consistent with their beliefs.