Wednesday, November 27, 2013

So you think you have QOS enabled your Lync?

Well think again……

We had a very interesting workshop with one of Microsoft’s PFEs this week, and the focus of this workshop was deep diving into Voice in Lync 2013.

One important aspect of Voice is the implementation of CAC and QOS in the customer network, end to end. Followers of my blog will know I am strong supporter the end-to-end user experience. As a part of this, my strategy is to try to convince all my customers to implement both QOS and CAC (implementing one without the other could actually worsen the experience for the end user).

Newsflash: Some of work you do to implement these function could be “slightly” in vain. With Lync 2013 CU came Lync mobility with the possibility to join audio, video and conference through WLAN on the mobile device. This is great, and I use it a lot. However, as I have suspected, and now confirmed; Mobile clients do NOT support CAC (nor are there any QoS mechanisms on the devices).

A consequence of this is over-subscription of the capacity configured in your network, and all clients in the subnets where mobile clients exist can all suffer bad quality. Seeing how popular the mobility has become, this can turn out to be a challenge for many a administrator.

I still believe you should implement QOS and CAC wherever possible, but now we have to be aware of the mobile “surprise”, and try to calculate this into the rest of your scheme. Let’s all hope Microsoft will look for a way to enable QOS and CAC for mobile devices (They have for common area phones, so why not the mobile devices?). I did not get a clear list of all devices not supporting CAC, but I will post an update once I can get hold of such a list.

Anybody else with a thought on how to handle the subject, or even better, experience from a deployment where this has been an issue?