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Nick Borelli

Collaboration Edge Mobile and Remote No Ringback External calls

Was wondering if anyone has come across this issue in deploying vpn'less Jabber with Expressway E and C deployment.  All internal calls generate a ringback tone, but dialing externally there is dead air till the call connects.  Our deployments are straightforward and there is ringback on all calls when connected via the vpn or internally with jabber.  This happens on both sip and pri calls.  Any help is much appreciated.  

V.Naveen Kumar

Hi Nick,

Check you have added annunicator in the MRGL of jabber Device Pool. if not added and try again.


Yes in every deployment all the jabber devices have the correct MRGL with annunciators in the device pool and even on the device itself.

Did issue go away after 8.5 upgrade? We have same issue with 8.2.



I have  smilar problem with my MRA deployment. Expressway version : 8.9

Some of outgoing calls does not provide ringbacktone via MRA.

TCT client associated MRGL (ıts contain annonciator.)

I upload working and non-working scnerio logs on attached.

Calll flow;

Expressway-E-->Expressway-C--> CUCM--> Sip trunk--> SBC


Israel Ramos



I have this exact problem, were you able to resolve it?




Brandon Nuner

I just finished getting these servers online and I have the same issue.. Nick, did you fix this?


Had a similar problem.

My solution was to changing the dial-peers on my pstn gateway (ISDN) connected to cucm via sip trunk. Unfortunately I don't know what I configured exactly... :/

Your outbound dial-peers?

The Config looks like:


voice call send-alert
voice call disc-pi-off
voice call convert-discpi-to-prog
voice service voip
 ip address trusted list
  ipv4 x.x.x.x
 allow-connections h323 to h323
 allow-connections h323 to sip
 allow-connections sip to h323
 allow-connections sip to sip
 no supplementary-service h225-notify cid-update
 fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback pass-through g711alaw
  h225 signal overlap
  call preserve limit-media-detection
 modem passthrough nse codec g711alaw redundancy
  bind control source-interface BVI10
  bind media source-interface BVI10
  sip-profiles 1
voice class codec 1
 codec preference 1 g711alaw
 codec preference 2 g711ulaw
 codec preference 3 ilbc
 codec preference 4 g729r8
voice class sip-profiles 1
 response 183 sip-header Remote-Party-ID remove 
 response 200 sip-header Remote-Party-ID remove 
 response 180 sip-header Remote-Party-ID remove 
dial-peer voice 10 pots
 trunkgroup pstn
 translation-profile outgoing topstn
 destination-pattern 0
 progress_ind alert strip
 no sip-register
dial-peer voice 200 voip
 destination-pattern [1-9].$
 progress_ind setup enable 3
 session protocol sipv2
 session target ipv4:x.x.x.x
 voice-class codec 1  
 dtmf-relay rtp-nte sip-kpml sip-notify
 ip qos dscp cs3 signaling
 no vad

Nick Borelli

I do not have a solution as of yet.  This happens with sip trunks, h323 and mgcp so far for all external calls.  Internal extension dialing has ringback.

Expressway does not support Early Offer audio at this point of time

 Unsupported features (general)
-- DTLS is not supported through the Expressway- C/Expressway-E; attempts to make secure calls will fail
-- SIP Early Media
-- SIP KeyPad Markup Language (KPML)

Correct SIP Early Media is not supported on the Expressway series devices.  I have however corrected the issue with my call flow.  Each call flow will have a different resolution.


Call flow;

MRA Device >> Expressway-E >> Expressway-C >> CUCM Cluster 1 >> SIP >> CUCM SME Cluster >> MGCP >> MGCP ISDN PRI.

Basically all I did was disable option "SIP REL1XX" on the SIP trunk between CUCM Cluster 1 and the CUCM SME Cluster.  Now my MRA endpoint receives a 180 Ringing message instead of a 183 with SDP.  The end result is that the MRA user hears ringing.  


The drawback is that you wont get early media from the telco provider that typically provide informational messages to the caller.  I like the drawback better than not getting ringing at all.

My call flow is as follows vcse-> vcsc -> cucm -> SIP -> CUBE PRI ISDN

Nick, I'm not sure if you're still having this issue or not.  


If you still do not have ringback from your MRA registered devices.. Can you run a debug on your VCSc (with PCAP) and determine how the ringing message is being delivered to the VCSc?  I'm guessing you'll find a 183 with SDP for ringing which you'll find coming inbound from a CUCM node and it wont be forwarded to the VCSe.


Please post your findings (screen shots or even the entire pcap).

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