| | 1 | = Some discussion and material on Control Channel based 802.11 design = |
| | 2 | |
| | 3 | |
| | 4 | ---- |
| | 5 | P. Kyasunur, J. Padhye and P Bahl, "On the efficacy of separating control and data into |
| | 6 | different frequency bands", |
| | 7 | ---- |
| | 8 | == Key Points == |
| | 9 | * Using separate frequency (lower range) and low data rate link for control channel message exchanges |
| | 10 | * Channel access contention and reservations done on the control channel |
| | 11 | * Adjustible ''k'' factor, prereservation for upto ''k'' packets, depending on how much time it takes to transmit data packet. |
| | 12 | * The benefits of using control channel versus packet size of the data packet are shown in following Figure [[Image(ccm.PNG)]] |
| | 13 | |
| | 14 | == Effect of packet size == |
| | 15 | Thus, for every control channel bandwidth, there is some optimum packet size threshold, such as the benefits of using control channel become significant. Since application level generates packet sizes that suit the application, in order to create this "optimum packet size" many such packets are aggregated together. |
| | 16 | |
| | 17 | == Effect of control channel range == |
| | 18 | * By using a control channel range that is close to the interference range of the data channel, all nodes in the interference region can be notified of the impending transmission, thereby preventing data packet collisions. |
| | 19 | * If the transmission range of the control channel is too large, then contention resolution process on the control channel will reserve an unnecessarily large area, reducing spatial reuse. |
| | 20 | |
| | 21 | == Protocol Architecture == |
| | 22 | The protocol architecture is shown in the following Figure [[Image(cca.PNG)]] |
| | 23 | |
| | 24 | |
