atcomsystems.ca/forum Forums General General Telephone & Systems Information Define: "Trunk" and "SuperTrunk"?

Hi folks,
I'm an I.T. guy who's trying hard to learn the telecom side of things, and I'm always confused when people refer to a "trunk" and also "supertrunk".

For example, our current data provider has a line item on our invoice titled "Supertrunk Channel Ter/DS1"

I think I get the DS1 phrase (that's Digital Service Level 1, i.e. a T-1 line, right?).

Can someone define the two terms - "trunk" and "supertrunk" for me and how they probably apply to my ISP?

Also, do you have any suggestions on how I might go about learning more about datacom - i.e., are there any good books on the topic, video tutorials, etc.?

Thank you!
Ed

Never heard the term here. It's got to be a term made up by that provider. My guess is that it is a dynamic T1.

It's been a long time, but I seem to recall one carrier pushing their T-1 trunks that were ESF (as opposed to AMI) as "Super Trunks".

There may also have been some talk of PRIs, as opposed to standard T-1s as "Super Trunks", but I think either way it was all just marketing-speak.

Sam

Sometimes the best approach is the direct approach. Ask them what they mean by the term, and ask them to show you a reference.

Same here term is not one I ever heard.

Maybe they are referring to bonding multi T-1"s.......

A "Supertrunk" is basically a T1 line that is not PRI. You get the full 24 channels. I run into them from time to time out here but they are usually older circuits.

They can be a real pain to configure because they are so configurable, especially when a system has defaulted. I've never had a provider able to tell me exactly how one should be setup. It's usually a crap shoot unfortunately.

What Styx1 said...old school T1 with 24 in and out channels. No caller ID. Alot were setup as E&M4 but AT&T switch interfaces in our area require the customer equipment to be programmed as DID trunks but would also allow outbound service on the channels. Haven't seen any in years since the acceptance of PRI formats. Blast from the past.

I've seen Supertrunk most referred to by AT&T, so it may be a marketing name coined by AT&T for their 24-channel T1. Like everyone has said, you don't see them too often. PRI is much more common now, and can deliver more features (like caller ID), as others have mentioned.

The chan term you reference how they describe each end of the circuit. If you look at your Customer Service Record, you'll see two addresses for the chan term, one at your site and the other at the central office (unless it's a point to point between your sites).

Justin

Here are a some terms and couple of factoids.

SF = Super Frame
ESF = Extended Super Frame
AMI = Alternate Mark Inversion
B8ZS = BiPolar with 8 Zero Substitution
PRI = Primary Rate Interface
ISDN = Intergrated Services Digital Network
E&M = Ear & Mouth

A PRI/ISDN T1 is provisioned as ESF/B8ZS. It can contain as many as 23 "B" (voice) channels and 1 "D" (data) channel.

A T1 that that features Loop Start, Ground Start or E&M can support up to 24 channels. If compression is applied on both ends of the circuit, the number of channels can be increased.