Clear Chanel Structured VS unstructered.

[shaftstri]

My understanding is Structured is TDM it has timeslots and unstructered doesnt.

Can some confirm this ?

ANd why would you want to use a Structured line for data only, is this due to the TELCO equipment being used that some can only offer structured because of their SDH/sonet infrastructure ?It seems most service offering DAT are chenelized.

PPP leased lines and lines useing HDLC these are synchronous end to end correct ?

Is this better the same doesnt matter cheaper ?

I have read alot of doc that suggests if your using CSS then this is clear channel as your other channels are clear ,anyone care to comment define the charecteristics of clear channel...on different services offered by TELCOS

What are the benifets of running chanelized circuits for data if any.Why are majority of DATA circuits channelized ?

What about other services DDS are they clear channel ?

It seems plenty of people use these terms and all give different answers.

Something not directly related ?

How does a a T1 pri work for voice and data 1 circuit

if i have 10 channels for voice PSTN access 10 for data how is the traffic marked for different delivery and switched routed ?

Lapd framing is ued for pri signalling at layer2 Q.921 and its balanced for voice ? SABME either user can send and recive whenevr DTE/DTE not relevant what about the 10 channels of data.. going to another site on the same pRI voice/data circuit ?

Hope this makes some sense

Thankyou.

[thomas.chen]

Answering a couple of your questions,

What are the benifets of running chanelized circuits for data if any.Why are majority of DATA circuits channelized ? By channelizing into 24 or 30, you are effectively using the Data circuits, this is the major reason for channelizing.

How does a a T1 pri work for voice and data 1 circuit ? T1 PRI is only used for Data, for voice T1 CAS is used which cannot be used for Data.

[shaftstri]

Hi Thomas,

You are incorrect !!! CAS is channel associated signalling Robbed bit they call it and is used in the US its very common and has gone through several iterations through to ESF extended super frame.

Bitts are used form the voice channels they are called a b c d bits these are used for various functions and are in band.Because CAS is stealing bits modem speed in the high range could suffer and do.

Its also much more efficient to have out of band signalling!!Look At the SS& network as an example!!

CAS is everywhere in the US though will be replaced by CCS which is used in ISDN PRI SS7 networks for out of band signalling.

PRI T1 is a type of ISDN, and includes 23 B-channels and one D-Channel. PRI T1 is used primarily for voice traffic, but also supports data and video applications

My question was why are we using chanelized circuits for data ?

And the structured VS non structured everyone has different answer I think this will be best explained by a DR of telecommunications