I often hear confusion about the conferencing capabilities in Office Communication Server and how this differs from the Live Meeting Service.

Much of the confusion I think comes from the fact that both solutions use the same client, the Live Meeting console.  The assumption is often that the offerings are the same - but they are not.  Or another common comment - "I am using Live Meeting" spanning both options!

Actually its a great example of our software plus services strategy, giving customers the choice to have conferencing delivered on premise (using OCS) or delivered as a service (Live Meeting) based on their preference.

Some of the main differences are as follows:

- Scale and SLA:  Using the Live Meeting Service backed by Microsoft's infrastructure means scale is not an issue, you just add users and we worry about the back end systems. 

Our guidance is that OCS based conferencing will only support 250 users, with the  Live Meeting Service this grows to 1250 per meeting, with unlimited meetings.  You can beyond this too with Event Services.

- Pricing: Conferencing for OCS comes as part of the OCS Enterprise CAL, so if you are investing in OCS for Voice and are buying the licence for this reason, then you could see it that conferencing comes as a bonus capability.  Pricing for the Service is licences based too but it is also possible to have a pay as you go (PPM / Price per minute) model working through some of our conferencing partners.

- Features:  There is a restricted set of features with OCS for conferencing.  I've already covered the scale limit but the other key ones include no ability to save recordings to the Service, restricted web based features eg Events and Marketing, Recordings etc.

There are many sides to the story, but if you looking for a quick simple way to get up and running with conferencing, the Live Meeting Service is probably for you.

For larger customers or for those who have made commitment to OCS, we often see a blended solution, with the Service being used for larger, more complex requirements.

For more information as always please go to www.microsoft.com/uc