What are hidden station problem and exposed station problem in WLAN? How are the problems solved?
Hidden station problem: B is sending data to A, and after some time C also wants to send data to B. but C is not in the range of B and so it will be unaware of the transmission between B and A, and so C will send data to A and therefore there will be a collision.
Exposed station problem: station A is sending data to B and C also wants to send data to D, but since C is in the transmission range of A, C will not send data to D. But the transmission between C and D will not affect the transmission between A and B.
The hidden node can solve be solved by the use of handshaking. B before sending data to A, will first send request to send (RTS) to A. after that if A is ready to receive data from B then it will respond by sending Clear to send(CTS) to B, which will also be received by C since it will also in the transmission range of A. as a result of which C will stop transmission for the time period that is been specified in the CTS.
The use of handshaking is unable to prevent handshaking. C stops transmission for the time period specified in the RTS as it is in the range of A, but does not receive the CTS send by B. as a result of which it send RTS to D, and if D sent CTS to C then it collides with the data sent by A to B(also received by C).
USE OF HANDSHAKING TO PREVENT HIDDEN NODE PROBLEM
USE OF HANDSHAKING TO PREVENT EXPOSED NODE PROBLEM
What is SRS? Write the features of SRS.
Why Required of ISO 9001:2000 standard?
Write a C program to print pattern below:
*
* *
* * *
* * * *
Define Quality Planning
Write a short note on Asymptotic Notations.