[cisco-voip] ISDN call takes long time before connecting

[Amit Kumar]

Hi Abebe,

I don't think we can do any thing for this delay. As router got no control
over incoming isdn messages.

Either they are waiting for some timer to get expired before they try to
route the call.

It also depends whether called subscriber is registered with same telco, or
there is another telco involved as well. It's also likely that target telco
is taking time.

Another point is setup ack,  which we got back from telco indicates that
they have configured overlap receive on this circuit.

You can simply ask them, if their pabx is doing overlap receiving on their
end

Thanks,
Amit
On 14-Oct-2014 7:56 pm, "Abebe Amare" <abucho at gmail.com> wrote:

> Hi,
>
> I am having a hard time convincing the local telco that outgoing calls to
> PSTN numbers take about 11 seconds before the voice router receives
> CALL_PROC from their switch. They insist this is normal and want to dismiss
> the case but the delay is noticeable. Incoming calls have no problem.
> The PRI line comes using microwave media due to lack of copper last mile
> to the site and it connects to Cisco 2901 voice router which connects to
> CUCM using SIP.
> I have sent them the output of 'debug isdn q931' as follows:
>
> *Oct 11 11:48:12.999: ISDN Se0/2/0:15 Q931: Applying typeplan for sw-type
> 0x12 is 0x2 0x1, Calling num xxxxxxxxx
> *Oct 11 11:48:12.999: ISDN Se0/2/0:15 Q931: Sending SETUP  callref =
> 0x00C2 callID = 0x8043 switch = primary-net5 interface = User
> *Oct 11 11:48:13.003: ISDN Se0/2/0:15 Q931: TX -> SETUP pd = 8  callref =
> 0x00C2
>         Bearer Capability i = 0x8090A3
>                 Standard = CCITT
>                 Transfer Capability = Speech
>                 Transfer Mode = Circuit
>                 Transfer Rate = 64 kbit/s
>         Channel ID i = 0xA9839F
>                 Exclusive, Channel 31
>         Calling Party Number i = 0x2180, 'xxxxxxxxx'
>                 Plan:ISDN, Type:National
>         Called Party Number i = 0x81, 'yyyyyyyyy
>                 Plan:ISDN, Type:Unknown
> *Oct 11 11:48:13.295: ISDN Se0/2/0:15 Q931: RX <- SETUP_ACK pd = 8
>  callref = 0x80C2
>         Channel ID i = 0xA9839F
>                 Exclusive, Channel 31
> *Oct 11 11:48:24.167: ISDN Se0/2/0:15 Q931: RX <- CALL_PROC pd = 8
>  callref = 0x80C2
> *Oct 11 11:48:31.127: ISDN Se0/2/0:15 Q931: RX <- ALERTING pd = 8  callref
> = 0x80C2
>         Progress Ind i = 0x8488 - In-band info or appropriate now
> available
> *Oct 11 11:48:39.975: ISDN Se0/2/0:15 Q931: RX <- CONNECT pd = 8  callref
> = 0x80C2
>         Connected Number i = '!', 0x83, 'yyyyyyyyy'
> *Oct 11 11:48:39.975: ISDN Se0/2/0:15 Q931: TX -> CONNECT_ACK pd = 8
>  callref = 0x00C2
> *Oct 11 11:49:06.119: ISDN Se0/2/0:15 Q931: TX -> DISCONNECT pd = 8
>  callref = 0x00C2
>         Cause i = 0x8090 - Normal call clearing
> *Oct 11 11:49:06.423: ISDN Se0/2/0:15 Q931: RX <- RELEASE pd = 8  callref
> = 0x80C2
> *Oct 11 11:49:06.423: ISDN Se0/2/0:15 Q931: TX -> RELEASE_COMP pd = 8
>  callref = 0x00C2
>
> Is there anything I can do from my side to lower this delay?
>
> best regards,
>
> Abebe
>
> _______________________________________________
> cisco-voip mailing list
> cisco-voip at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-voip
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://puck.nether.net/pipermail/cisco-voip/attachments/20141014/86e052c6/attachment.html>