Thoughts - the fight for SIP SRVs between Cisco Jabber and Lync depolyments?

[Chris Swinney]

Hi all,

I suppose this is more a discussion rather than a direct question, but I would like to know your opinions.

We maintain a large VC network spanning many organisations. The has been based mainly on H.323 but we are trying to move toward SIP and so are requesting institutions add SIP SRV into their Internet DNS zones to point to the relevant VCS-Es.

However, a lot of the institutions are are looking to deploy Lync into their organisations - they are all essentially MS AD environment with Exchange and SharePoint, so it seem like s sensible option for them. Of course even though you can effectively trunk between the VCS and Lync server pool, at this moment in time only Lync 2010 is supported with a poor resolution (ignoring silly options like the AMG). although current (and upcoming) software from Cisco will support Lync 2013 and higher resolutions.

However, then we run into a quandary. Most institutions would want their users to be contatcable via a SIP URI that matches their e-mail address, and this is generally the root domain name of an organisation. I would love to be able to say that then should point the SIP SRV to the VCS-E, but they will want to point these toward the MS Lync server pool. Of course, we could point a secondary sub domain (i.e. video.domain.com) to the VCS and the root to the Lync pool, but is there any way we could get a a user to have both Lync and Jabber with the SAME URI (although I fear this would be also be regarded as confusing).

What do others do? Throughts and answer of a postcard (or just reply in this thread...)

Cheers

Chris

[Paulo Souza]

Hi Magnus, thanks!

I have read all the VCS guides, literally, this is the only one I have never read, because I didn't receive a project involving VCS and Lync integration yet.

This doc is in my "read list" however.

Regards

Paulo Souza

Please rate replies and mark question as "answered" if applicable.

[Chris Swinney]

Cheers Guys, some interesting comments - especially relating to the SIP SRV records and thier difference with Lync and a standard based SIP systems. This is didn't know as I misread the initial SIP SRV required for Lync thinking they conflicted (d@mn my dyslexia!).

I'm actually running through a basic Test Lync depolyment at this moment in time to see how we can set it up with the VCS - but what I really waiting for is x8..... (sooooon Chris, sooon....)

.

[Chris Swinney]

One or two other question regarding this subject and moving onto the actual  integration of the Cisco Videoconferencing infrastructure and Lync. I see  from above that we could actually use the same root external DNS zone to point to both the Lync servers AND the VCS-E without issue as they use different SRV records (ignoring backward compatibility with OCS), but is it possible or even advisable to host the same domain on both environments when integrating, or should they be different? The deployment guide actually shows an example scenario with different domains for the Lync and VC deployments. Maybe I am simply misreading the deploment guide (very likely), but I can't seem to find this outlined.

There is some talk above about the the use/non-use of  FindMe, however, I have just read in the "Microsoft Lync 2010 and Cisco  VCS - Deployment Guide" (page 17) that a FindMe licence is a pre-requisite prior to configuring Cisco VCS and Lync to interoperate. This in itself  might put us a bit on the back foot as we were looking to the potential  to integrate organisations Lync deployment with their current video  deployment, where a lot of VCS-Cs do not currently have the FIndMe licence.

To complicate matter further, we are not  able to follow the Cisco recommended deployment with a separate VCS/Lync  Gateway - as we have over 50+ organisations we simply cannot afford an  additional 50+ VCS-Cs!, although we recently had a conversation with our  Cisco partner and Cisco themselves say that this should be fine although  there are some limitations. For our purposes, we are mainly looking at  enabling simple video communication between the Lync world and standards  based VC world. I have included a sample diagram below and although I  have included Jabber clients, I doubt there will be too many institutions that will incorporate both Jabber AND Lync.Shame, but there you go. It also menas that things like presence and muitlplle user endpoint ringing may not be required by us.

Please note that I haven't included third party callers, I have just update the image to include third parties with standards based SIP/H.323 being routed via the VCS-E and Lync will come in via federated organisation and the Lync Edge Server. Ideally, all users should be able to contact and be contactable via all other users a and organisations.

To sum up, in this scenario:

1. What is the requirement for configureing SIP domains in each of the requirements, even though we now know that is is possible to route a single domain to both Lync AND VCS, should they still be seperate?
2. What is the actual requirement for a FindMe licence on the VCS-C?

Message was edited by: Chris Swinney  Updated image to include third parties

[Chris Swinney]

I have been thinking over this problem and come to a few conclusions about these questions

1. I suppose that if you want to enable external standards based SIP clients to be able to dial Lync client, then the single domain idea with SRV records pointing to both Lync edge server AND VCS would be the way forward - sure I suppose you could set up a new address space, but this would just seem to make things complicated for the user. This means that the VCS above would need the dial plan to forward calls on to both Lync and potentially registered VCS endpoints.
2. I also suppose that if endpoints on the VCS and Lync all use the same domain and alias, then it would be again be down to the Dial Plan to determine the potential for where the call is routed. I assume that the same rules apply to the way that the VCS handles calls placement via search rules and that if the VCS finds multiple alias in multiple zones (say through parallel searches of the same priority), then the call will be passed onto the first zone that responds. This means that only one end point (as far as the VCS is concerned) would ring (of course if the call is passed over the the Lync environment then potentially Lync will ring multiple devices?). With FindMe, then multiple alias could be defined and could be called at the same time - however, juts like FindMe is NOT required in the standard setup, I don't see why it would be required for Lync deployment, there are simply some caveats to take into consideration.

I do wonder what would happen on the Lync side if a call was placed to an alias of the same domain and even if this would be forwarded onto the VCS/Lync Gateway. However, I have just setup a demo Lync domain to test this so I'll see if I can figure it out.

I think the other thing that may need to be taken into account is if the is an "in house" remote Lync user that wished to place an call to and external standards based SIP client - in which case I believe the Extended OCS licence would be needed. I'm not sure if this applied to and external third party Lync user wishing to call a standard based SIP user in mydom.com organisation.

[Chris Swinney]

Well, I have a setup now in test that uses NO FindMe and I must say it works OK. Of course the limitations are with the potential to fork calls to different devices but this is try of an VCS deployment that doesn't run FindMe. We have used the same SIP domain on both the VCS and the Lync domain, so depending on where a user is registered and the search rules that have been implement, would depend upon how a device/user is looked up and called. For the majority of our particular installation, it should work just fine.

I can still see the benifit of setting up a seperat SIP domain for room based VC units, but for users, a single domain and address seems plausaable.

This essentially answer my question 1) and 2) posed above.

The issue now, as I see it, comes not particularly with the VCS deployment or set up, but the the setting of static rules on the Lync deployment. In a simple example in the deployment guide mentioned above, a single domain is forwarded through the Trusted Application to the VCS/Lync gateway. We expanding this slightly to forward a know SIP domain hosted on an entirely different VCS-C/VCS-E installation. Indeed, the deployment guide goes on to say (page 52):

Note: Static routes should only be set up where absolutely necessary, e.g. for allowing ad hoc calls to an MCU:
...
     
If static routes are set up, VCS will receive any requests to that domain that Lync cannot handle, and thus may receive significant volumes of mis-dial traffic.

Now this is all fine and dandy, but what if you actually want Lync users to be able to video call ANY standards based SIP endpoint (in the same way that a Jabber client could do), AND any Federated Lync endpoint?

In the same note, it states that the Lync will first check all registrations BEFORE failing back to a static route. But does this mean that it will check Federation as well before failing back to a static route? Further, Lync can be deployed not only to deal with Video, but more often that not will be looked upon for Voice calls. I can see that potentially routing all such calls through the VCS might be a step too far (especially WRT to call licensing), but still there may be a need to actually offer router all video calls to an unknown destination.

In essence, on the Lync side (and if there is anyone out there that might be able to answer this I would be greatful), I would like to know a few things:

1. Can a static route be set up to forward ALL unknown address via a trusted application (in a similar vein to a default gateway)?
2. Will all other possible routes through Lync (such as federated sites) be check before failing back to a static rule?
3. Is it possible to set up a static rule to ONLY forward video based calls?

On the VCS side of things:

1. What methods are their to monitor the actual resource usage of the VCS (i.e. CPU utilisation, memory usage, Ethernet port loading etc).

On the latter, I just ran a quick search in the VCS admin guide for the term "CPU" and came up with nothing! The VCS is a Linux box at the end of the day so I do assume that such monitoring would be available - but where and how?