Limiting outbound ISDN calls to a limited number of channels

[sluijterr]

Hello,

I need some help on the next question from an customer of us. The situation is as follows:

An ISDN trunk with 30 channeld (E1): needs to be splitted up in:

10 channels for inbound, 10 channels for outbound, 10 channels for overflow for both.

It's a H323 gateway and CUCM. I was thinking of the next model:

!

Trunk group ISDN-Incoming

MaxCalls 10

!

Trunk group ISDN-Outgoing

MaxCalls 10

!

Trunk group ISDN-Overflow

MaxCalls 10

!

!

interface Serial0/0/0:15

description BASICVOIP

no ip address

encapsulation hdlc

isdn switch-type primary-net5

isdn incoming-voice voice

isdn send-alerting

isdn bchan-number-order ascending

trunk group ISDN-Incoming

trunk group ISDN-Outgoing

trunk group ISDN-Overflow

no cdp enable

!

!

dial-peer voice 951115 pots

trunkgroup ISDN- Outgoing

preference 1

description OUTBOUND-OTHER

destination-pattern *#0.T

progress_ind setup enable 3

progress_ind alert enable 8

progress_ind progress enable 8

progress_ind connect enable 8

!

!!

dial-peer voice 9511152 pots

trunkgroup ISDN- Overflow

preference 2

description OUTBOUND-OTHER

destination-pattern *#0.T

progress_ind setup enable 3

progress_ind alert enable 8

progress_ind progress enable 8

progress_ind connect enable 8

!

!

dial-peer voice 1007 voip

description ** DDI calls to CUCM Sub 1 ** preference 1 destination-pattern 88951....

progress_ind setup enable 3

session target ipv4:10.10.10.10

voice-class codec 1

voice-class h323 1

trunkgroup ISDN-Incoming

dtmf-relay h245-alphanumeric

ip qos dscp cs5 media

no vad

!

!

dial-peer voice 1007 voip

description ** OVERFLOW DDI calls to CUCM Sub 1 ** preference 2 destination-pattern 88951....

progress_ind setup enable 3

session target ipv4:10.10.10.10

voice-class codec 1

voice-class h323 1

trunkgroup ISDN-Overflow

dtmf-relay h245-alphanumeric

ip qos dscp cs5 media

no vad

!

The problem is you cannot place more then 1 trunk group on the serial. Is there anotherway to reach the goal?

thank you in advance.

rg

Remco

[Sreekanth Narayanan]

Hi Remco,

This cannot be done. E1 PRI is designed such that there will be 2 signaling channels for all 30 data channels and therefore, you will not be able to split the PRI into 3 groups as per the customer's requirement.

You can talk to the provider and ask them to send incoming calls to the customer site only on the last 10 channels, but there isn't a way for you to send 10 calls on the first 10 channels out and stop when the 11th call tries to go out. So it's a dead-end there too.

Thanks

Sreekanth

[Aman Soi]

Hi ,

this is good DOC 

https://supportforums.cisco.com/document/98726/how-route-outgoing-calls-through-specific-isdn-channels-e1t1

regds,

aman

[Ayodeji Okanlawon]

Here is what you can do...

1. inbound--This is out of your control. You will need to tell your telco to send inbound calls to eg first 10 channels..channels. channel1-10. If those are busy they should overflow to channel (whatever you want to use eg 21-30

2. For outbound you can use channel 11-20. You will need the following configuration

conf t:

trunk group OUTBOUND
 description ****  Outgoing PSTN Trunk Group*****

controller e1 0/0/0

pri-group timeslots 1-31

trunk-group OUTBOUND timeslots 11-20

int serial 0/0/0:15
 no ip address
 isdn switch-type primary-ni
 isdn incoming-voice voice
 no cdp enable
 trunk-group OUTBOUND

dial-peer voice 2 pots
 trunkgroup OUTBOUND
destination-pattern XXXXXXXX (whatever your dial plan is)
 progress_ind setup enable 3
 progress_ind alert enable 8

[Sreekanth Narayanan]

I was not aware of the trunk-group timeslots under controller. That's a good thought!

[sluijterr]

Thnx for your reactions, I'm going to study them and try in my lab. Only  the moment i'm busy with a customer project, but after that I'll work on it!

thnx

Remco