Dicsonnect supervision on T1

[ttech]

Twice in the past week I have been subbed to do a cutover to a T1 on the Legend. Both R7's Neither one of them would disconnect when the far end hung up(on 2 different providers) It is usually an option that is set in the channel bank but the T's were directly into a 100D card so there was no dhannel bank

I ended up having the Ts re-provisioned for Ground start and they disconnected correctly.

I had set LS Disconnect as reliable but to no avail.

Am I missing something here?

Don

 

[merlinman]

I had one this last week that the vendor was using a channel bank, but they had trouble between their switch and the channel bank.

So by switching to Ground Start, you probably got the best fix available.

Most of the time these vendors provide E&M Tie Lines.

I wonder why they didn't in this case?

(Of course, usually they are selling what they call "TWO WAY D-I-D".)

 

[ttech]

They wanted line apperances on the console. I tseems that Disconnect supervision is something that is automatically built into Groung start trunks.

 

[Dexman]

Take it from a C.O. tech, having loop start trunks on a dedicated T1 circuit is an open invitation to both headaches and hung ports.

Suppose that a user has a T1 circuit, loop-start trunks and an auto attendant that answers all inbound calls. A caller dials a toll-free number that rings down on any one of the channels of the T1. The auto attendant answers the call and gives the caller a list of options to consider. The caller, possibly calling on a cellphone in an area with lousy coverage, or from a landline and simply not wanting to deal with an automated system, drops the call. There is no positive disconnect signal for the originating switch to pass on down to the Legend. Thus, a default telephone will eventually ring with nobody on the line for the poor person to speak with. If no default extension is programmed, the port will get hung in the phone system.

T1E&M is the best choice for signaling to use on a T1 circuit . Ground-start comes in a close second. Loop-start is a distant third .

 

[merlinman]

Yes, you could get T1 E&M, but the last time I did that, the vendor could not do Imediate/Imediate. Therefore, it took a full 2 seconds to get dial tone.

So I guess in this case, Ground Start was the way to go.

Of course, the other issue is the Customer is living in the STONE AGE, but we will not go there.

 

[Dexman]

It's odd that a switch cannot be provisioned for T1E&M immediate.

I work on a Nortel DMS-500 and an Alcatel DEX-600E and both of those guys can handle both versions of T1E&M. I'm sure a Lucent 5E can as well.

I wonder what type of switch was on the other end of the circuit?

Oh well.

 

[merlinman]

I have no idea, I think a 5-ESS either REEAL or EMULATED.

I would blame the programmers there for not knowing how to set it up.

But I would also place blame on the Sales Folks for not selling PRI.

That would have solved so many issues here, but this was one of those things that I had to just show up and do the programming after the fact, thus, no input from the LEGEND design engineer.

I just had to make it work with what I had.