Channel Allocation Problem
The channel allocation problem is the problem of assigning channels to users in a multi-user system. There are a number of different channel allocation algorithms, each with its own goal. Some channel allocation algorithms aim to maximize the total throughput of the system, while others aim to minimize the delay or jitter experienced by users.
Carrier Sense Multiple Access with Collision Detection (CSMA/CD)
CSMA/CD is a variation of CSMA that uses collision detection to further reduce the number of collisions. If a station detects a collision, it immediately stops transmitting and waits for a random amount of time before trying again
A network with CSMA/CD has 10 Mbps bandwidth and 25.6 μs maximum propagation delay. What is the minimum frame size? (This solution is for micro second not mili second)
Data:
L = size of frame
BW → bandwidth = 10 Mbps = 10 × 10^6 b/s
Tp → propagation time = 25.6 μs = 25.6 × 10^-6 s
Tt → transmission time
Formula:
For CSMA/CD,
Tt ≥ 2 × Tp
\({{\rm{T}}_{\rm{t}}} = \frac{{\rm{L}}}{{{\rm{BW}}}}\)
Calculation:
\(\frac{{\rm{L}}}{{{\rm{BW}}}} ≥ 2 × T_p\)
L ≥ 2× Tp × BW
L ≥ 2 × 25.6 × 10^-6 × 10 × 10^6
L ≥ 512 bits
Lmin = 64 bytes
Therefore, the minimum size of a frame in the network is 64 bytes.
