Wang and Ng In conclusion, in this section we have presented practical system solutions to the challenges in transport layer of Wireless Sensor Networks. The receiver sends a message to the source that specifies the rate at which it wants the source to send the packets. TCP Multi-Home Options Another transport protocol with native multihoming is SCTP To complement the ideas herein introduced, we recommend that readers interested in further protocol details consider the following references: Rather than TCP, real-time streams make use of the Real Time Transport Protocol (RTP) for transport, which is implemented on top of UDP.
When a packet gets to the destination, an ACK is generated and sent back to the source. The congestion avoidance algorithm is used when the SSIZE is greater than the threshold SSTHOLD. that is only running TCP will be approximately fair to all users. �-@n0Xk���_lɰN]?�_y�b��ٙ��KFޭ1���o4K�c�3���l����J���3�0���4�A�$��N��,0h�H������qk ��e �?��K�#�,l=�D�2HK��7U5�l/����X�d�q�'?n�1�b�
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To rephrase the question: How do congestion control algorithms work and how is congestion detected?This is assuming you have to use UDP (TCP would be preferred). The only effective way to control congestion is for the transport protocols to send packets into the network more slowly. Mechanisms have been invented to prevent network congestion or to deal with a network collapse: The SSTHOLD is the slow start threshold used to control the amount of data flow on the network. When the third duplicate ACK is received, set STHOLD no more than STHOLD = max (FlightSize / 2, 2*SMSS), where FlightSize is the amount of outstanding data in the network The disadvantage here is the sender need to wait for the timeout to happen. For each additional duplicate ACK received, increment SSIZE by SMSS. If the packets arrive normally, then the receiver can request an increased rate, say a linear increase. I'm still figuring out how to implement send and receive windows in order to implement packet resend and flow control over UDP.
It generates periodic RTCP Receiver Report (RR) packets that are sent back to the source. Congestion control Congestion control can be used to calculate the amount of data the sender can send to the destination on the network.
Congestion occurs when these buffers gets filled on the destination side.
If it really was that way the question wouldn't arise.
How can I detect congestion on the LAN to slow the rate of UDP packets being sent?EDIT: please, no comments on the use of UDP whether it's suitable or not. When congestion occurs, the destination has only two options with the arriving packets, to drop it or keep it.
The packet loss is determined when the timeout happens.
Since most of the mechanisms described in this chapter were designed for use on the Internet, and therefore were originally defined in terms of routers rather than switches, we use the term In such an environment, a given source may have more than enough capacity on the immediate outgoing link to send a packet, but somewhere in the middle of a network its packets encounter a link that is being used by many different traffic sources.
The function of TCP (Transmission Control Protocol) is to control …