VoIP Gateway ring delay 2

[Crowtalks]

I have a Norstar VoIP Gateway attached to A MICS 7.0 that communicates with a few BCMs. MCDN is not in play in this setup.

Calling across the network between the BCMs gives immediate ring tone on the callers end. Calling through the Gateway either to the MICS or from the MICS results in a 6 to 8 second delay before the callers hear the ring tone. I have tweaked settings in the Gateway with no effect.

Any ideas?

 

[NTL555]

the norstar VOIP gateways use auto answer with LS/DS or CLID trunk cards. With Auto Answer in play, there is a 2 ring delay cycle on a Norstar MICS/CICS. Callers will hear 2 rings before the customer will hear 1. No way around it, unless you get a gateway that communicates via T1/E&M with the Norstar system.

NTL555

 

[Crowtalks]

OK, I'll buy that... what about the 6-8 second delay when you call from the MICS to one of the BCMs?

 

[RikRodgers]

Are you able to measure latency across the network on that connection?

 

[Crowtalks]

Yeah, latency is almost nonexistent with an average of <30ms.

 

[NTL555]

is that your dial timeout? does hitting the # help?

NTL555

 

[Crowtalks]

I haven't tried hitting the # with this setup...I'll have to do that

 

[bighands2468]

Email from Nortel Addressing calling from MICS to MICS. You should not have a delay calling to a BCM.

Response:

As per the Distributor Technical Reference Bulletin: DTR-2004-0521-NA, Date: 17 December 2004 ,Norstar VoIP Gateway Ring-back delay,

In some scenarios a user initiating a VoIP call to a Norstar with a Norstar VoIP Gateway connected could experience a delay before ring-back is heard.

A call to a Norstar VoIP Gateway that has the DID option (Digit Delivery table) configured can experience up to 9 seconds of delay before the ring-back is heard. These delays are caused by a series of call processing steps that are inherent in the way the Norstar processes DID information.

Possible actions to reduce Ring-back delay

• With two or more Norstar systems networked using Norstar VoIP Gateways, configure the Gateways to play ring back tone to the Norstar system by setting the "Play ringback Tone to Tel" parameter to "Play".

This will play a ring back tone to the calling party as the call is being setup. Depending on the line and set configuration for busy treatment in the Norstar, the caller may hear ring-back tone followed by busy tone. This can be avoided by proper configuration of the sets and lines. For example forward busy to voice mail for the set, and ensuring that a prime set is defined for the physical lines. Please note: When the ringback tone from Norstar cuts in there will be a momentary break in the ringback cadence since it is not synchronized with the gateway ring cadence

If you choose not to implement the above actions the following additional actions will minimize the silent period before ring-back starts.

• Ensure that "#" is dialed after the phone number has been entered. This is only applicable for gateway to gateway calls.

o This indicates the end of dial digits and eliminates the standard time-out delay waiting for additional digits.

• Use "P" or "PP" instead of "D" prior to digit delivery. This can be adjusted in the Digit Delivery Table.

o Each "P" inserts a 1.5 second pause before the digits are delivered from the Gateway to the Norstar system instead of waiting for dial-tone which could take up to 6

 

[Crowtalks]

Thanks Bighands2468.

I'll have to try these tweaks, especially the P instaed of the D in the Digit Table.