Lecture 14: Carrier Sense
نویسنده
چکیده
Last lecture, we looked at the ALOHA protocol for medium access control (MAC). The ALOHA protocol pioneered two main ideas: the ability to detect and handle collisions on a shared medium and the use of randomization to decide whether to transmit a packet or not. However, ALOHA was designed for situations where none of the users could hear any of the other users transmitting. Real-world wireless deployments are not always this bad, and oftentimes users do have the ability to hear each other’s transmissions—an ability called carrier sense. This lecture, we’ll look at a few examples of how to incorporate carrier sense into the MAC protocol.
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