Call Adminission Control over MPLS

[Turbo727]

Hi All,

This question probably has been asked a million times. but I can't find a straight answer other than a high level cisco document.

This is a typical senario, multiple offices interconnected via MPLS network, one is HO where call manager resides in and other offices are just remote sites.

All sites are put into a dedicated location and regional respectively.

When set up location, call manager asks bandwidth between other locations. but since this is a hub-spoke topology (mpls is the hub and other sites are spoke), we would like to limit bandwidth per site for traffic going into the mpls cloud regardless of where it actually goes.

How can i tell call manager the mpls cloud is hub, seems no where I can assoicate the hub location to the mpls cloud.

is there a way to set this up?

Any input would be appreciated.

[Jonathan Schulenberg]

Assuming CUCM version is 8.x or earlier in this answer. There is a new option in 9.x.

You just mentally decide that MPLS is the Hub_None location. Every location you define is a spoke logically connected directly to Hub_None. So, if everything is in a location OTHER than Hub_None then all that is left is the MPLS cloud itself.

Please remember to rate helpful responses and identify helpful or correct answers.

[Turbo727]

Thanks for the info. 

Actually, it's ver 9.1. What's the new option? Bandwith manager? How does it work in this scenario. Thanks.

[Jonathan Schulenberg]

In 9.1 you can define whatever topology you want and are not forced to use Hub_None as your hub. In most cases it still makes sense to though. This mostly helps customers with non-hub and spoke designs such as:

• regional sites that aggregate point-to-point circuits from each location in the area and then connect upstream into an MPLS.
• one-off remote buildings or satellite sites that don't cost justify an entire MPLS circuit but has a limited bandwidth tie-line or VPN tunnel back to a site that does.
• country- or continent-specific WANs that have a fusion site but are not redundant.

Another way to say it is that locations can now be multiple hops away from the hub, or you can even have multiple hubs to represent your different WANs around the globe.

8.x example:  SiteA --- Hub_None ---SiteB

9.x example: SiteA --- Region1 --- Hub_None --- Region 2 --- SiteB --- Second_Hub --- SiteC

One important caveat is that ELCAC cannot handle redundant paths (either active or standby) nor asynchronous routing. For either of those situations you still need RSVP.

Please remember to rate helpful responses and identify helpful or correct answers.