10-09-2014, 10:12 AM
Wireless ATM&Congestion Control
Wireless ATM.ppt (Size: 602 KB / Downloads: 10)
ATM (Asynchronous Transfer Mode)
In ATM networks, the data is divided into small, fixed length units called cells. The cell is 53 bytes. Each cell contains a 5-byte header, which comprises of identification, control priority and routing information. The rest 48 bytes are the actual data. There are two fundamental types of ATM connections
Some Early Debates
Open-Loop Vs Close-Loop
1st one do not need end-to-end feedback,but In 2nd approaches,
the source adjusts its cell rate in responding to the feedback
information received from the network.
Credit-Based Vs Rate-Based
Credit-Based approaches consist of per-link, per-VC window
flow control. Rate-Based approaches control the rate by which
the source can transmit
Binary Feedback Vs Explicit Feedback
Binary Feedback uses on bit in the cell to indicate the elements
along the flow path is congested or not In Explicit Feedback,
the network tells the source exactly what rate is allowed for it
to send
Conclusion
WATM has the potential to bring wireless networks a new generation
The success of WATM will be highly relies on the success of ATM/B-ISDN in wired networks
Both ATM and wireless communicates have put a lot of attention on Wireless
This report introduced the concepts in congestion control for ATM networks, and the specifications for ATM Congestion Control ATM traffic control proposed by ATM