Interactive end-of-chapter exercises


Supplement to Computer Networking: A Top Down Approach 8th Edition


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Random Access Protocols: Aloha

Assume that there are 3 active nodes, each of which has an infinite supply of frames they want to transmit, and these frames have a constant size of L bits. If two or more frames collide, then all nodes will detect the collision.

There are two versions of the Aloha protocol: Slotted and Pure. In this problem we will be looking at the efficiency of these two variations. In the case of Slotted Aloha, frames will be sent only at the beginning of a time slot, frames take an entire time slot to send, and the clocks of all nodes are synchronized.

Please round all answers to 2 decimal places.


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