Shared medium

In <a href="/facts/Telecommunication/vxoj1cxR">telecommunication</a>, a shared medium is a <a href="/facts/Transmission_medium/yT1uXLmq">medium</a> or <a href="/facts/Channel_(communications)/MtlxEShV">channel</a> of <a href="/facts/Information_transfer/cDXdYmhQ">information transfer</a> that serves more than one user at the same time.
In order for most channels to function correctly, no more than one user can be transmitting at a time, so a <a href="/facts/Channel_access_method/CdCGxpcu">channel access method</a> must always be in effect.
In <a href="/facts/Circuit_switching/fJ3vdmAB">circuit switching</a>, each user typically gets a fixed share of the channel capacity. A <a href="/facts/Multiplexing/YE7hK8cw">multiplexing</a> scheme divides up the <a href="/facts/Channel_capacity/55wJYsS6">capacity</a> of the medium. Common multiplexing schemes include <a href="/facts/Time-division_multiplexing/tv7bMh1v">time-division multiplexing</a> and <a href="/facts/Frequency-division_multiplexing/lgj6TMU1">frequency-division multiplexing</a>. Channel access methods for circuit switching include <a href="/facts/Time-division_multiple_access/ue5UzN7B">time-division multiple access</a>, <a href="/facts/Frequency-division_multiple_access/mQTBIpzA">frequency-division multiple access</a>, etc.
In <a href="/facts/Packet_switching/olDlDP1R">packet switching</a>, the sharing is more dynamic — each user takes up little or none of the capacity when idle, and can utilize the entire capacity if transmitting while all other users are idle. Channel access methods for packet switching include <a href="/facts/Carrier-sense_multiple_access/uUMMF4ex">carrier-sense multiple access</a>, <a href="/facts/Token_passing/9cw7bA4f">token passing</a>, etc.

Shared medium open-in-new

Shared medium