Haiku #14

A voice cries out in

The wilderness – oh, wait, she's

In Room 42.


There are definitely a lot of advantages to the Voice over IP (VoIP) technology, the technology that enables people to make phone calls over the Internet instead of using the old-fashioned public switched telephone network. (You know, the PSTN network, the phone system?) At the same time, however, there's definitely a built-in disadvantage to Voice over IP phones. As a general rule, you can cart a VoIP phone with you everywhere you go and, as long as you have an Internet connection, you can use that phone and your same phone number. That's not true of a PSTN phone. Instead, PSTN phones are tied to a physical address. Suppose your home phone has the phone number (425)-555-1219. Can you unplug that phone and plug it into the phone jack in your office? You bet you can. However, that phone (that is, that piece of hardware) will no longer use the phone number (425)-555-1219; instead, it will have whatever number has been assigned to the phone jack in your office.


So why is that a disadvantage of the VoIP phone? Well, to be honest, it's not always a disadvantage. But suppose your house catches on fire. If you make an emergency call from a phone connected to the PSTN network, the fire department can immediately identify your exact physical location. However, that's not true if you call using a VoIP phone: like we said, VoIP phones are not tied to a physical address, which means you could be calling from pretty much anywhere. At best the fire department might be able to determine the IP address of the phone, which, in turn, would let them narrow the search down to, say, the entire west coast of the United States. "Get in the truck, boys," the captain would command. "There's a fire at!" It just doesn't work.


So is there a way to work around this problem with VoIP phones? Of course there is, and Microsoft's solution to this dilemma – the fact that emergency responders can't automatically determine the location of a caller using Enterprise Voice – is the Enhanced 9-1-1 service (more popularly known as E9-1-1, or even E911) introduced in Lync Server. With E9-1-1 (currently available only in the US, which means that anyone planning on having an emergency in the next few months should move to the US as soon as possible), administrators can create a database of their organization's physical layout: buildings, rooms, wireless access points, switches and subnets, you name it. In turn, any time someone makes an emergency call from within the organization, Lync Server can use the information in that database to determine the actual physical location of the caller: Building 3348, Room 42, 1 Microsoft Way, Redmond, WA 98052.


Admittedly, that's a somewhat superficial overview of the E9-1-1 service, but it gives you an idea of what the service is meant to do. By default, the E9-1-1 service is disabled when you install Lync Server, which makes sense: the odds are pretty good that you won't have your location database up and running at the time you install Lync Server. After you do have the database up and running, you can then enable and disable the service by using the CsLocationPolicy cmdlets: Get-CsLocationPolicy, Grant-CsLocationPolicy, New-CsLocationPolicy, Remove-CsLocationPolicy, Set-CsLocationPolicy, and everyone's favorite, Test-CsLocationPolicy. And when you do that, then emergency responders can determine the location of anyone making an emergency call from within your organization. That means you'll no longer be a voice crying out in the wilderness; instead, you'll be a voice crying out in Building 3348, Room 42, 1 Microsoft Way, Redmond, WA 98052.


To enable the E9-1-1 service at the global scope, all you have to do is run a command as simple as this:


Set-CsLocationPolicy –EnhancedEmergencyServicesEnabled $True


That's pretty slick, but there are all sorts of other cool things you can do with location policies. For example, if the Location Information Server is unable to determine a user's location, you can require the user to manually enter a location before they can make a call. You can configure the service so that location information is only used for emergency calls; that way, your location is not generally available to teammates and other users. You can even set things up so that a third-party (such as your own local security team) can participate in any emergency call placed from within your organization. And all done through location policies.


Yeah, we thought they were pretty cool, too. And we're not easy to impress!


Note. Wouldn't the characters on the television show Lost have benefitted from having the E9-1-1 service installed on the island where their plane crashed? Probably. On the other hand, if they did have the E9-1-1 service installed they could have called for help, rescuers would have known exactly where they were, and the entire cast would have been rescued before the end of the first episode. Not a very satisfying way to end a TV series, although, from what we've been told, it wouldn't have been any less satisfying than the way the series really did end. (Although, then again, compared to the way the Newhart show ended no series finale will ever be anything but ho-hum.)


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