Token Passing
With both CSMA/CD and CA/CA , the possibility of visions is always there, and the more hosts that are placed on the wire, the greater the chances of collisions, because you have more systems "waiting" for the wireless to become free so that they can send their data.
Token passing takes a totally different approach to deciding on have on how a system can place data on the wire. With token passing, there is an empty packet running around on the wire - the "token. " In order to place data on the wire, you need to wait for the token; once you have the token and it is free of data, you can place your data on the wire. Since there is only one token and a host needs to have the token to "talk, " it is impossible to have collisions in a token - passing environment.
For example, if Workstation 1 wants to send data on the wire, the workstation would wait for the token, which is circling the network millions of times per second. Once the token has reached Workstation 1, the workstation would take the token off the network, fill it with data, ark the token as being used so that no other systems try to fill the token with data, and then place the token back on the wire heading for the destination host.
All systems will look at the data, but they will not proceed it, since it is not destined for them. However, the system that is the intended destination will read the data and send the token back to the sender as a confirmation. Once the token has reached the original sender, the token is unplugged as being used and released as an empty token on to the network.
With both CSMA/CD and CA/CA , the possibility of visions is always there, and the more hosts that are placed on the wire, the greater the chances of collisions, because you have more systems "waiting" for the wireless to become free so that they can send their data.
Token passing takes a totally different approach to deciding on have on how a system can place data on the wire. With token passing, there is an empty packet running around on the wire - the "token. " In order to place data on the wire, you need to wait for the token; once you have the token and it is free of data, you can place your data on the wire. Since there is only one token and a host needs to have the token to "talk, " it is impossible to have collisions in a token - passing environment.
For example, if Workstation 1 wants to send data on the wire, the workstation would wait for the token, which is circling the network millions of times per second. Once the token has reached Workstation 1, the workstation would take the token off the network, fill it with data, ark the token as being used so that no other systems try to fill the token with data, and then place the token back on the wire heading for the destination host.
All systems will look at the data, but they will not proceed it, since it is not destined for them. However, the system that is the intended destination will read the data and send the token back to the sender as a confirmation. Once the token has reached the original sender, the token is unplugged as being used and released as an empty token on to the network.
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