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HSL over TDM / ATM

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Wallis Dudhnath - 5th October 2016  (13:38 GMT)

ATM and TDM are two types of data transfer technologies. TDM stands for Time-division multiplexing, which is a method of combining multiple data streams into one and sending it together over one signal. ATM stands for Asynchronous Transfer Mode. It is based on a fixed "cell" that is used to convey a Multimedia payload, i.e. Voice, Data, etc..

Summary: ATM uses "cells" whereas TDM uses a "nailed up" TimeSlot to convey information. Internally, HSL uses ATM "cells".

Over 20 years ago when TDM was overloaded with the signalling load there was the move to 2Mbits/s HSL. This was an interim step before the full adoption of Sigtran (SS7overIP).

GURJIT SINGH - 5th October 2016  (08:31 GMT)

Want to know ATM HSL Bandwidth

galal Ajlouni - 8th August 2012  (11:25 GMT)

Would you please help me to get the formula how to calculate link load (in erlangs) for ATM-HSL (High speed link) .

Tauhid - 31st October 2010  (07:18 GMT)

Can anybody describe a little what is the difference between ATM and TDM?

Nikhil - 19th March 2010  (08:46 GMT)

I want to know difference between TDM HSL and ATM HSL

MTN - 19th May 2008  (14:30 GMT)

Hi Tuannd,

As I know that the HSL is over ATM, but its can be over TDM but its will be as simulation and its will be 30 % use of the 2 Mbps.
Also in TDM you can use the total bandwidth or the total E1 but fractional 30 channels .

Tuannd - 25th April 2008  (03:01 GMT)

Dear friends

I am looking for the difference between HSL over TDM and HSL over ATM: the principles, standards and dimensiontion guide. Can anybody help me? many thanks!!

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