Recall that with the CSMA/CD protocol, the adapter waits K.512 bit times after a collision, where K is drawn randomly. For K = 100, how long does the adapter wait until returning to Step 2 for a 10Mbps Ethernet? For a 100 Mbps Ethernet?
Can anyone help me with the formula to calculate? Thank you!
To calculate how long the adapter waits until returning to Step 2 in the CSMA/CD protocol, we need to calculate the waiting time in terms of bit times. The waiting time (W) can be calculated using the formula:
W = K * 512 / B
Where:
- W is the waiting time in bit times
- K is the randomly drawn value for K
- 512 is the number of bit times it takes for a minimum-sized Ethernet frame (64 bytes) to be transmitted on the network
- B is the bit rate of the Ethernet network
For a 10Mbps Ethernet:
W = 100 * 512 / 10,000,000
W ≈ 5.12 microseconds
For a 100Mbps Ethernet:
W = 100 * 512 / 100,000,000
W ≈ 0.512 microseconds
So, for K = 100, the adapter waits approximately 5.12 microseconds on a 10Mbps Ethernet and 0.512 microseconds on a 100Mbps Ethernet before returning to Step 2.