OCS Has built in mechanisms to publish the OCS Environment to the internet, the OCS EDGE Server provides those functionalities.  While many companies rely on VPN they often do not see the added value of what an EDGE Server can bring to the table.

Let’s compare Remote Access :

Remote Access is provided by the OCS EDGE server

• Eliminates the need to use VPN for OCS Access, It’s transparant for the End-Users because they don’t have to start their VPN connection before Communicator can be used.  Automatic logon is performed whether you connect from the LAN or from the Internet.
• It enables federation with Business (they also require OCS with EDGE)
• It enables federation with Public IM providers such as Windows Live, Yahoo & AOL
• The Windows Mobile OC Client also connects through the EDGE Server
• It enables the use of Live Meeting externally and makes it possible to use anonymous meetings so that customers & others can join meetings as well

Remote Access is provided through VPN

• No EDGE required
• Does not always work as expected.  In most cases VPN endpoints cannot do Peer to Peer calls – no routing of VPN clients.  Additionally an EDGE Server can solve these issues for VPN Users.
• It’s Not transparant to End-Users
• There is additional overhead for VPN tunnel and does not optimize the use of the Microsoft codec
• If there is a requirement for 2 Factor Authentication then VPN solution is the only way to go but you can still use the EDGE Server for other features