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Posted By: bcousins Audible ringback on MICS with PRI - 02/05/07 12:30 PM
I have two Norstar MICS with 5.0 software that we were converting from T-1 to PRI. When we cut over to PRI, calls would go thru but the calling party (calling into the MICS) did not have audible ringback. We have worked this problem with Qwest tier 3 support and they are quoting me the Bellcore standard SR4994 - ISDN CPE guidelines section 5.1 "Audible ring tone shall be provided by terminal CPE." There is not a setting on the MICS that controls this. The Qwest is providing the circuit from a 5ESS. This is occurring on 2 different MICS coming from 2 Different central offices (both Qwest, both cut the same day, both probably built at the same time by the same person since they were on the same order.) Qwest is insisting that this is being caused by the MICS. They have put a protocol analyzer on the circuit and captured a call both thru the switch and with the switch removed. both sessions came back the "CPE" was not sending the ringback tone signaling.

I am at a loss. I have talked to a number of other techs and no one has ever had this problem on a Norstar. Any help would be appreciated.

Thanks,
Barb
Posted By: 5Etek-mike Re: Audible ringback on MICS with PRI - 02/05/07 04:27 PM
Barb,
In follow up to my PM, your post indicates that your provider's policy requires them to provision your PRI to receive the ringtone from your local system(s). I'm not very familiar with Norstar/MICS systems, however, if your MICS does not control the providing of ringtone back to the provider, let's see if other members may be able to add their input based on their MICS experience, and how they adressed any problems similar to yours. Please understand that I wish to refrain from discussing 5E translations (even though the translations do provide for ringtone control and treatment) in respect of your provider's policy, not that I disagree or agree with them.
Posted By: bcousins Re: Audible ringback on MICS with PRI - 02/05/07 05:05 PM
Mike,
I understand your hesitancy. I was hoping you could tell me somewhere either in the trunk group or the Pri provisioning where there might be a parameter they could change to allow ringback.

Barb
Posted By: 5Etek-mike Re: Audible ringback on MICS with PRI - 02/05/07 05:14 PM
PM sent
Posted By: sentrex1 Re: Audible ringback on MICS with PRI - 02/05/07 06:14 PM
Hi Barb I have several customers with pri's on mics and myself i have never had to ajust anything for when calling into the mics
i have pri's from different providers as well,
also i have never heard thru the grapevines about
this problem but maybe here in canada we have different protocols.
Also when i have to call our telco providers,
here they always come with the answer looks good on our side,its gotta be your equipment
hope this helps you
Posted By: bcousins Re: Audible ringback on MICS with PRI - 02/06/07 07:47 AM
Sentrex1- Teir III tech support with the provider has been working with me. They have come out to the site and monitored the circuit with a protocol analyzer and captured a session (live call) and they say that they are not seeing the Norstar send back the signaling information to generate ringback tone. They have quoted Belcore standard SR4994 ISDN CPE Guidelines Section 5.1 "Audible ringtone shall be provided by the terminating CPE." They said they have looked at all the provisioning and can't find a problem on their end.

I was hoping someone else may have had a problem like this and could give me some insight. Also if anyone is familiar with the 5ESS programming and or 5E and Norstar that they may be able to point me in the right direction when speaking with my provider. I do not know alot about the 5E and I may be using the wrong terminology.
Posted By: 5Etek-mike Re: Audible ringback on MICS with PRI - 02/06/07 08:38 AM
Barb,
Have them check for any special "BRCS" features assigned in their 5E "Recent Change/5.4 views", to make sure that the BRCS features on the the "no-ringtone" PRI match the BRCS features assigned to your other customer's good PRI.
Posted By: bcousins Re: Audible ringback on MICS with PRI - 02/06/07 09:26 AM
Mike,
I have them checking. I asked them for a printout of the trunk group configuration but they said it was proprietary.
Posted By: SSPhone Re: Audible ringback on MICS with PRI - 02/06/07 09:32 AM
Are the PRI's set for NI2?
Posted By: bcousins Re: Audible ringback on MICS with PRI - 02/06/07 09:44 AM
Norstar is set up as:
Hardware=PRI - Lines 001-023 Protocol=NI2 NSF ext=None
Bchan seq=Descend
CBC Routing= FX=None 800=None
CO Fail=TIA 547A
IF levels=ISDN
Framing=ESF
Internal CSU=on
CSU line buildout=0
Line coding=B8ZS
Clock Source= Primary

Also have made sure all 23 lines are provisioned
Under lines is set up PRI-A no prime set.

All calls both inbound and outbound complete. The problem is when a caller calls in, they will not hear audible ringback tone. They will hear silence and all of a sudden the customer (norstar) will answer the call. Most people calling the customer will hang up and try again because they think the call is not going thru since they are not hearing ringback tones.
Posted By: 5Etek-mike Re: Audible ringback on MICS with PRI - 02/06/07 10:09 AM
"Hardware=PRI - Lines 001-023 Protocol=NI2 NSF ext=None"

Does the "ext" setting allow you to change from the "none" (default) to "WATS"? From what I can find the WATS setting is for 5ESS.
Have you matched this information with your other customer's PRI? Are both MICS using the same software version?

I advise having a Certified Nortel Technician confirm this, and take over coordination with the folks from Qwest. Unfortuneately, I'm not qualified on the Nortel Norstar MICS Systems, and I do not want to accidentally misadvise you, accidentally resulting in increasing the protocol issue. Please understand. smile
Posted By: JimmyT Re: Audible ringback on MICS with PRI - 02/06/07 02:05 PM
From Nortel Software Release Notes.

Enhancements made over MICS 5.0 WI 6.00

No Ringback tone on inbound calls

Customers calling into the Norstar system from the public network on PRI trunks will not get ringback tone from the Norstar. Those installs using the private networking or MCDN functionality will not be affected. The lack of ringback tone will be encountered when using any of the following protocols:
• NI2
• DMS 100
• DMS 250
• 4ESS
Customer installations using PRI connections directly to the central office will be the only sites affected by this issue. For those sites utilizing PRI trunking in M1 private networked environments installations will be unaffected. Customers using analog only installations will also be unaffected.

This has been addressed in MICS 5.0 WI 6.02
Enhancements made over MICS 4.1.1 WI 6.15
PRI
Posted By: bcousins Re: Audible ringback on MICS with PRI - 02/06/07 02:07 PM
UPDATE....PROBLEM RESOLVED
Got hold of an old ITAS technical bulletin.
It seems that 5.0 software has a problem that was corrected with Maintenance Release 5.0 WI 6.02 software. Apparently the people who sold this customer the switch never upgraded to the maintenance release since they were not using ISDN/PRI at the time.

Thanks for all of your help.
Barb
Posted By: 5Etek-mike Re: Audible ringback on MICS with PRI - 02/06/07 02:34 PM
Excellent! I'm glad that Nortel's 6.02 Software Release will provide ringtone to your customer's callers.

Thank you JimmyT and Barb for sharing this important software fix.
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