Mike Stacy's Blog

Creating OCS Address Book Entries for Polycom RMX Meeting Rooms

In case you’re not familiar with the Polycom RMX, it’s a platform of audio/video MCUs that can integrate with everything from voice PRIs to legacy video devices to the newest 1080p endpoints.  Starting with version 4.1 (current version as of this writing is 5.0), it also supports integration with OCS.  Specifically, OCS users can call into the RMX via audio or video by simply making a Communicator call to an RMX meeting room or entry point.  The RMX can bridge those MOC users with other non-OCS SIP endpoints as well as H.323 endpoints.  For more information on the RMX check out Polycom’s website.  While it’s fairly easy to call a meeting room from Communicator by dialing it manually, for folks that use MOC in conjunction with RMX meeting rooms consistently it is desirable to have quick dial access to the rooms.  An easy way to do this is using contact objects in Active Directory.

First, create a regular contact object in Active Directory.  You can enter any information you’d like in the required fields, just be sure to make the Display Name match what you’d like your users to see in the OCS address book.

Next, use adsiedit to assign a SIP address to the contact.  If you do not have adsiedit installed, just download the appropriate Windows Support Tools for the system you are using.  Once they are installed you can launch adsiedit via Start –> Run –> adsiedit.msc:

Next, navigate the Domain context to the location of your contact object and open its properties.  Scroll down to msRTCSIP-PrimaryUserAddress.  You’ll notice that it currently has no value set:

Enter the address in the format sip:<MeetingRoomID>@<RMXRoutingAddress>.  For example: sip:1000@rmx.domain.com.

Because you’ve defined a SIP address for the contact, OCS will automatically add it to the address book.  However, be aware that the address book only synchronizes every 24 hours at 1:30am local time (by default).  You can force the address book to regenerate faster using the abserver –syncnow command.  Be sure to allow time for AD replication before you run the address book synchronization.  For more details on the address book see http://technet.microsoft.com/en-us/library/ee323612(office.13).aspx.

Once the address book has synchronized and your client has downloaded the updated address book file, you will be able to find the room by name in MOC.  Since the RMX is not registering to OCS the presence will show as unknown, but assuming that your environment is configured correctly you will be able to make audio and video calls to that contact from the address book just like you can by manually typing in the SIP address.

A couple odd issues

I hit a couple odd issues in a recent deployment that I thought were worth sharing with others.  Sort of a throwback to the old “Notes from the field” book for anyone who used to be an Exchange 5.x admin…

No address book

Symptom:  User’s search in Communicator yields no result.  Other users can search the ABS without a problem.

Troubleshooting & Fix:  Checked to make sure Galcontacts.db was downloaded.  It was.  Deleted it and signed in again.  The file was recreated as expected, but with a time stamp 4 minutes in the future (?).  Time sync between the workstation and DC was fine.  Checked running processes to see if there was anything out of the ordinary and came across the Spybot Search & Destroy Resident Engine.  Disabling this fixed the problem.  Apparently galcontacts.db is considered malware by Spybot.

Audio calls sound horrible

Symptom:  Outbound voice quality on certain PCs is so choppy that audio calling is unusable.  MOC user can hear inbound voice just fine.  Laptops and other devices have excellent call quality both directions.

Troubleshooting & Fix:  Ensured the CPU was relatively idle, which it was (high CPU = bad audio).  Eliminated the network infrastructure as the culprit by connecting a known good system to the exact same cable as one of the problem PCs.  Audio was fine in this configuration.  Ensured it wasn’t the sound card by recording a quick wav file without issue.  No leads yet.

Started poking around Device Manager to see what hardware we’re dealing with.  Noticed that the embedded NIC was made by NVidia (they make NICs?).  Found the latest drivers for the NIC and sound card and applied them to no avail.  Even though all other network performance was fine I just wasn’t happy with a NIC made by a graphics company.  We disabled it in the BIOS and added a spare NIC and that did the trick – call quality started to function normally.

Filtering Contacts from the Address Book

Last night I was working with my friend and fellow UC architect, Peter Pawlak, on a customer design item.  This particular customer is a subsidiary of a larger organization.  The subsidiary is deploying OCS but the parent company is not.  Not a problem since each of them have their own forests.  However, the parent company pushes down it's users as contacts via an LDAP replication tool.  The issue was that the subsidiary is deploying telephony integration in their OCS deployment and the contacts that are coming from the parent company include phone numbers that are not formatted in such a way that they could be accounted for in the normalization rules (too many different formats).  There were also duplicate phone numbers and other similar issues.  In the end it was decided that the best plan of action was to simply exclude these contacts from the address book altogether.

To do this we used address book filtering.  If you aren't familar with address book filtering, check the section around Table 19 of the OCS Technical Reference (page 78).  What we had to do was find an attribute that did not exist for contacts but did exist for users and groups.  We settled on SAMAccountName and Peter made the appropriate changes to the AbUserEntry table in SQL, excluding objects that do not have a SAMAccountName attribute by setting the 0x8000 flag for that attribute.  This ensured that all users and groups were still included in the ABS.

Unfortunately the address book filtering capability for OCS is very basic, so you can't do things like string comparisons or value matching.  There is a resource kit tool that provides a UI for updating the AbUserEntry table, but I have seen that tool cause problems so I don't recommend using it unless you are extremely uncomfortable making the changes in SQL yourself (make sure to take a backup first if you do this in a production environment!).

Hopefully MS will consider more advanced filtering capabilities as this is a common request from customers.