Network Site Routing

A workaround for the previous scenario is to base emergency services routing off of the same network location information that might be defined for Call Admission Control and Media Bypass.

After the sites are configured, follow these steps for each site that has an E911 registered phone circuit:

1. Create a PSTN usage and voice route for the emergency call.

2. Create a user location policy with emergency services enabled. Enter the emergency services number and mask.

3. Assign the PSTN usage to the location policy.

4. Assign the location policy to the network site.

The end result is that Lync clients that sign in on network subnets associated to that site automatically receive that PSTN usage, and it is inserted at the top of their voice policy. A normalization rule for the emergency number based on the mask also is inserted. As the users move between offices, a PSTN usage and route for the local gateway are always inserted, ensuring that their emergency calls are sent out the media gateway in the office where they are currently located.

The advantage here is this works only for internal Lync clients. The location information is not exchanged for remote users, so users signed in through an Edge Server won’t be able to make emergency calls. Organizations should review these options with a legal team, but informing the users that emergency services calls can happen only within the office might be acceptable.