17
edits
More actions
no edit summary
No edit summary |
No edit summary |
||
|
-Error Correction: Receiver not only detects whether errors have been intorduced in the frame but also determines exactly where in the frame the errors have occured.
-Half-duplex and full-duplex: With full-duplex the nodes at both ends of a link may transmit packets at the same time.
Channel Partitioning Protocols
Time division multiplexing
-The Good
-Eliminates Collisions
-Perfectly fair
-The Bad
-Each node is limited to an average of the bandwidth even if its the only one talking
-A particular node is the only one with something to say, it can't say it all at once it must take breaks
Code division multiplexing
-The Good
-Different nodes can transmit simultaneously
Random Access Protocols
When there is a collision, each node involved in the collision repeatedly retransmits its frame until the frame gets through without a collision. It doesn't necessarily retransmit right away however. It waits a random ammount of time to retransmit thus decreasing the probability of future collisions on the same frame.
Carrier Sense Multiple Access With Collision Detection (CSMA/CD)
-Listen before speaking: If someone else is talking then wait until they are finished
-If someone else begins talking at the same time, stop talking: Collision detection!
Taking Turns Protocols: Most popular is Token Ring.
| |||