Performance of TCP
in Wireless Networks
Transmission Control Protocol
Reliable ordered delivery
Implements congestion avoidance and control
Reliability achieved by means of retransmissions
Acknowledgements sent to
We have seen that mobile users can change point of
In a WLAN, a mobile changes access point.
In a cellular network, a mobile changes base station.
A mobile user can work at office and at home at
different in a day: mobile chang
Medium Access Control
What is media access control?
No need for controlling
access to the medium
We need to control the access
to the shared channel
- Otherwise collisions will occur
Media access co
Wireless Local Area
Networks and 802.11
Wireless LANs are local area networks established using shortrange wireless link technologies.
Range: ~100 300 m
A wireless LAN is similar to the Ethernet, but uses wireless links.
Relationship between frequency and wavelength
Why is it more difficult to communicate using higher
frequencies of the radio spectrum?
Why is it easier to communicate using lower frequencies
of the radio spectrum?
Whats the difference be