Simulate Balanced Sliding Window Protocol in C Simulate Balanced Sliding Window Protocol in C.docx (Size: 14.39 KB / Downloads: 182) BALANCED SLIDING WINDOW PROTOCOL This is a symmetric protocol that allows information to be sent reliably in both directions. Home CN Third year Selective Repeat Sliding Window Protocol. Selective Repeat Sliding Window Protocol by Vaibhav Kumbhar. Selective Repeat: With the use of multiple frames for a single message, the stop-and-wait protocol does not perform well. Only one frame at. Sliding window algorithm is used to perform required operation on specific window size of given large buffer or array. Window starts from the 1st element and keeps shifting right by one element. The objective is to find the minimum k numbers present in each window. This is commonly know as Sliding window problem or algorithm. Sliding Window protocol handles this efficiency issue by sending more than one packet at a time with a larger sequence numbers. The idea is same as pipelining in architectures.
• In sliding window method, multiple frames are sent by sender at a time before needing an acknowledgment.
• Multiple frames sent by source are acknowledged by receiver using a single ACK frame.
We’ll be covering the following topics in this tutorial:
Sliding Window
• Sliding window refers to an imaginary boxes that hold the frames on both sender and receiver side.
• It provides the upper limit on the number of frames that can be transmitted before requiring an acknowledgment.
• Frames may be acknowledged by receiver at any point even when window is not full on receiver side.
• Frames may be transmitted by source even when window is not yet full on sender side.
• The windows have a specific size in which the frames are numbered modulo- n, which means they are numbered from 0 to n-l. For e.g. if n = 8, the frames are numbered 0, 1,2,3,4,5,6, 7, 0, 1,2,3,4,5,6, 7, 0, 1, ….
• The size of window is n-1. For e.g. In this case it is 7. Therefore, a maximum of n-l frames may be sent before an acknowledgment.
• When the receiver sends an ACK, it includes the number of next frame it expects to receive. For example in order to acknowledge the group of frames ending in frame 4, the receiver sends an ACK containing the number 5. When sender sees an ACK with number 5, it comes to know that all the frames up to number 4 have been received.
Sliding Window on Sender Side
• At the beginning of a transmission, the sender’s window contains n-l frames.
• As the frames are sent by source, the left boundary of the window moves inward, shrinking the size of window. This means if window size is w, if four frames are sent by source after the last acknowledgment, then the number of frames left in window is w-4.
• When the receiver sends an ACK, the source’s window expand i.e. (right boundary moves outward) to allow in a number of new frames equal to the number of frames acknowledged by that ACK.
• For example, Let the window size is 7 (see diagram (a)), if frames 0 through 3 have been sent and no acknowledgment has been received, then the sender’s window contains three frames – 4,5,6.
• Now, if an ACK numbered 3 is received by source, it means three frames (0, 1, 2) have been received by receiver and are undamaged.
• The sender’s window will now expand to include the next three frames in its buffer. At this point the sender’s window will contain six frames (4, 5, 6, 7, 0, 1). (See diagram (b)).
Sliding Window on Receiver Side
• At the beginning of transmission, the receiver’s window contains n-1 spaces for frame but not the frames.
• As the new frames come in, the size of window shrinks.
• Therefore the receiver window represents not the number of frames received but the number of frames that may still be received without an acknowledgment ACK must be sent.
• Given a window of size w, if three frames are received without an ACK being returned, the number of spaces in a window is w-3.
• As soon as acknowledgment is sent, window expands to include the number of frames equal to the number of frames acknowledged.
• For example, let the size of receiver’s window is 7 as shown in diagram. It means window contains spaces for 7 frames.
• With the arrival of the first frame, the receiving window shrinks, moving the boundary from space 0 to 1. Now, window has shrunk by one, so the receiver may accept six more frame before it is required to send an ACK.
• If frames 0 through 3 have arrived but have DOC been acknowledged, the window will contain three frame spaces.
• As receiver sends an ACK, the window of the receiver expands to include as many new placeholders as newly acknowledged frames.
• The window expands to include a number of new frame spaces equal to the number of the most recently acknowledged frame minus the number of previously acknowledged frame. For e.g., If window size is 7 and if prior ACK was for frame 2 & the current ACK is for frame 5 the window expands by three (5-2).
Sliding Windows Replacement
• Therefore, the sliding window of sender shrinks from left when frames of data are sending. The sliding window of the sender expands to right when acknowledgments are received.
• The sliding window of the receiver shrinks from left when frames of data are received. The sliding window of the receiver expands to the right when acknowledgement is sent.
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Here you will get a sliding window protocol program in C.
In PC systems sliding window, the protocol is a technique to transmit information on a system.
Sliding window protocol is applied to the Data Link Layer of the OSI model. At information connection layer information is as edges.
In Networking, Window basically implies a cradle which has information outlines that should be transmitted.
Both sender and recipient concur on some window size. In the event that window size=w, at that point subsequent to sending
w outlines sender hangs tight for the affirmation (ack) of the principal outline.
When the sender gets the affirmation of a casing it is supplanted by the following edges to be transmitted by the sender.
On the off chance that beneficiary sends a group or aggregate affirmation to sender, at that point it comprehends
that more than one casings are appropriately gotten, for eg:- if ack of edge 3 is gotten
it comprehends that casing 1 and casing 2 are gotten appropriately.
In sliding window protocol the beneficiary must have some memory to remunerate
any misfortune in transmission or if the casings are gotten unordered.
Effectiveness of Sliding Window Protocol
η = (W*tx)/(tx+2tp)
W = Window Size
tx = Transmission time
tp = Propagation delay
Sliding window works in full duplex mode
It is of two kinds:-
Particular Repeat: Sender transmits just that casing which is incorrect or is lost.
Sliding Window Protocol In Computer Networks Ppt
Return n: Sender transmits all casings present in the window that happens after the blunder bit including mistake bit too.
Sliding Window Protocol Program in C
The following is the creation of sliding window protocol in C.
Output
Sliding Window Protocol Program in C++
Remark beneath in the event that you have any inquiries with respect to the above program.