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omnet++veins

Veins 802.11p CSMA/CA and retransmission

Vehicles communicate using 802.11p on Veins 5.1, OmNET 5.6.2, sumo 1.8.0 environment.

My questions

  1. Do I have to implement retransmission process(like CSMA/CA) when collision is occurred? or, is retransmission process(like CSMA/CA) already implemented in library or such class?

  2. I want to use RTS/CTS option, do I have to implement it too?

Thank you

Solution

  • To directly answer your question: the 802.11p modules that are included in Veins 5.1 trigger automatic retransmissions (following the 802.11 specification) for lost unicast messages if the MAC layer useAcks parameter is set to true (which is not the default). RTS/CTS is not implemented, so if you want to use only modules from Veins you would need to implement this yourself.

    More generally, though, your research sounds like it might be better served if you would combine Veins with The INET Framework (via veins_inet); this would allow you to use the more general 802.11 simulation model included in The INET Framework. It includes features like block-ACKs, RTS/CTS, fragmentation and reassembly, infrastructure mode, automatic rate selection, and many more.