SX 20 with cucm to call outside

[Hythim Ali El Hadad]

Hi,

we have two SX 20 registered to CUCM

how these sets call outside units also how other units call us through internet

Do we need expressway with rich media session license only ?

and how calls done

thanks

[PJMack]

Hello, 

Yes you will need to setup Expressway Core and Edge servers. A basic deployment would probably suit your needs, here is the deployment guide which covers how it works and how to set it up. 

https://www.cisco.com/c/dam/en/us/td/docs/voice_ip_comm/expressway/config_guide/X8-10/Cisco-Expressway-Basic-Configuration-Deployment-Guide-X8-10.pdf

[Patrick Sparkman]

In addition to PJMack's comment, see Cisco Expressway and CUCM via SIP Trunk Deployment Guide (CUCM 8,9,10,11 and X8.8).  You will need an RMS license for every concurrent B2B call made.

[Hythim Ali El Hadad]

Thanks for your replies
Only I need to understand how the call done

For example in our LAN, 2 SX20 registered to CUCM. and another one working standalone
How to call from standalone unit to the one registered to CUCM and also how to call from the one registered to CUCM to the standalone unit ?

Thanks

[Acevirgil de Ocampo · Accepted solution]

Hello,

Take note that CUCM supports only SIP and once the SX20 endpoints are registered on the CUCM, H323 service will be disabled on the endpoints so incoming/outgoing call using IP dialing will be disabled. If your H323 standalone endpoint and SX20's SIP registered are located inside your network, this will be a challenge for you.

IP dialing is only possible on endpoints registered on CUCM if the IP you want to call is located outside your network. And the Expressway Core and Edge will do the work for this. It means the call from SX20 will go through CUCM to the Expressways and to the endpoint.

This link may help: 

https://www.cisco.com/c/en/us/support/docs/unified-communications/telepresence-video-communication-server-vcs/118884-config-vcs-00.html

Is there a reason why you cannot register the standalone endpoint to your CUCM? 

Thanks and regards,

ACEVIRGIL

[Hythim Ali El Hadad]

Hi Acevirgil,

Thanks a lot for your reply

It make the things easier

There is no need to deploy standalone units. Only I was trying to understand the scenario

I see in the link you provided how to enable CUCM registered sets to call IP through expressway

I have another questions:

What is the pattern that outside endpoints will dial to reach me, either h323 or SIP end points ?

Also do I need only a rich media session license per every concurrent call through the expressway ?

Thanks again

[Acevirgil de Ocampo · Accepted solution]

Hi,

Thank you for rating the post.

To answer your questions,

1. What is the pattern that outside endpoints will dial to reach me, either h323 or SIP end points ?

Once your endpoints are registered on CUCM with given extensions, they can be reached from outside endpoint by dialing their full SIP URI address in the format of extension@domain. If one of your endpoint have the extension 123456 and you have the external routable domain for example company.com, external endpoint will dial 123456@company.com to reach that endpoint. The "company.com" is a domain that have SRV records on Public DNS so you need to create records for that domain. SIP URI dialing heavily depends on DNS.

Take a look at Cisco Expressway Basic Configuration Deployment Guide (X8.10) under Appendix 2: DNS Records on pages 55-56.

2.  Also do I need only a rich media session license per every concurrent call through the expressway ?

Yes. As mentioned on the previous posts Rich Media Session (RMS) licenses are required on both Expressways. 1 call through the Expressways will consumed 2 RMS licenses, 1 on Core and 1 on Edge. So it is a best practice in licensing that the number of RMS license on both Expressways should be the same.

I hope this clears your question.

regards,

ACEVIRGIL

[Hythim Ali El Hadad]

Thanks again for your kind reply

So I can use the same Expressway used for MRA or should use another one

if my EXPe domain is abc.com

so outisde callers will dial 123456@abc.com

And it'll reach EXPe which will pass it to EXPc and it will send it to CUCM. Is it right ?

Is there any link for needed configuration on expressway or it is sufficient to configure what you sent in the first link

Thanks

Haitham

[Acevirgil de Ocampo · Accepted solution]

Hi,

Yes, use the same Expressways. MRA and B2B calls are achieved on same pair of Expressway.

if my EXPe domain is abc.com

so outisde callers will dial 123456@abc.com

And it'll reach EXPe which will pass it to EXPc and it will send it to CUCM. Is it right ?

---

- Absolutely right! As long as you have the proper SRV records on Public DNS and resolvable FQDN for your Expressway Edge the calls will be routed to your Expressway Edge -->Expresseway Core --> CUCM --> Internal Endpoint.

Assuming you have already configured your Expressways and CUCM to work with MRA, the one I provided on the first post will be used if you want to enable IP dialing from inside to external IP's.

And if you will enable B2B for outside endpoints to reach your endpoints registered on CUCM, this link will help you for straight forward steps. 

http://info.stack8.com/blog/configuring-business-to-business-sip-uri-dialing-with-cisco-expressway

But you need to have the Cisco Expressway Basic Configuration Deployment Guide (X8.10) as your reference while doing the configuration if needed.

Br,

ACEVIRGIL