Lync Protocols and Ports for Windows Phone 7 Application

The Lync Protocols and Ports app is now available for download from Windows Phone 7 Marketplace. This mobile application helps engineers, IT professionals, and field consultants configure the 15 most common communication points in a Lync environment. Using the Lync Protocols and Ports app, you can quickly find the protocol and port that needs to be opened between any two endpoints in the Lync environment. After download, the app doesn’t require internet connectivity, which makes it easy to use in secured or remote locations.

Author: Kaushal Mehta

Publication date: September 2011

Product version: LYNC Server 2010

A comprehensive Microsoft Lync Server 2010 environment can include 15 communication endpoints. These 15 endpoints extrapolate to 225 possible communication links. For a feature to work, these endpoints must be configured correctly. The Lync Server 2010 communication endpoints are shown in the below diagram.

Figure 1. Lync Server 2010 communication endpoints.

Figure 2 illustrates the connections between an Internal Lync client and every other endpoint in the environment. Similar mappings can be made for each source and destination endpoint.

Figure 2. Lync Server 2010 communication endpoint link connections.

Given the large number of potential links, it’s easy to miss opening a link. For example, an internal Lync client communicates with the internal Edge interface over UDP port 3478. If the link is not configured correctly, the connection will fail. A failed connection means the Lync client cannot acquire Media Relay Authentication Service (MRAS) candidates. This failure affects features, such as Audio/Video calls with an external user, desktop sharing, and so forth. Using the Lync Protocols and Ports app, the administrator enters the source and destination endpoints into the application. The application then displays which protocols and ports should be open. For example, when an internal Lync client needs to communicate with the internal Edge interface for MRAS candidates, the administrator selects Internal Client as the source and Internal Edge as the destination. Then the administrator selects Open ports to see which protocols and ports to open. Figure 3 illustrates the results of this combination and was taken from the application running in a Windows Phone 7 emulator.

Figure 3. Open ports required for Internal Client to Internal Edge connection.

Some link combinations are not valid. For example, an external Lync client cannot connect to a Survivable Branch Appliance. When you try to map an External Client to a Survivable Branch Appliance, the app displays NA, indicating the connection is invalid. Figure 4 displays the results of mapping an External Client to a Survivable Branch Appliance.

Figure 4. Invalid link combination generates NA results.


The Lync Protocols and Ports app for Windows Phone 7 helps administrators quickly determine which protocols and ports need to be opened in their Lync environment. After installation, the app does not require an internet connection, which makes it ideal for secure locations.

We want to hear from you

Missing a protocol or port? Need more communication points in the app? Please post your comments, and we’ll update the app as quickly as possible.

Additional Information

To learn more about Lync Server 2010 protocols and ports, check out the following:

Lync Server Resources

We Want to Hear from You

Keywords: LYNC Server, MRAS, STUN, LYNC Protocols, LYNC ports

Comments (5)
  1. Tobie Fysh says:

    Not the Windows Phone 7 application I'm waiting for <hint hint>

  2. Ed says:

    I'd rather have the actual Phone app than a phone app that tells me the same information that's on a single page i the documentation.

    Over a year without a phone app. I've got a number of customer that is just amazed by this. It didn't take much longer to actually develop Windows 7!

  3. Mike Reiring says:

    Agree w/ Tobie.  Where's the app we really want?  Mango is out.

  4. Yeah Yeah, we HEAR ya all 🙂 ..

Comments are closed.

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