Question

We have a chat application which works on ASP.Net web applications. We want to allow users to make calls to other users through our chat application. To provide that we want to make use of Microsoft Lync 2010 and use their SDK to leverage its capabilities and make calls. Any pointers on how to do that will be of great help.

Answer 1

You have a couple of options here – you could use the NameCtrl control to integrate presence and a pop-up menu into your aspx pages – see my answer here for more details, and an example.

Assuming you’re not using Silverlight, you could create a .NET assembly that uses the SDK to initiate a call (see the walkthrough here), and then expose this to COM using .NET’s COM Interop features – example here, if you haven’t done this before

Also, Sevki’s answer is a great way to get up and running quickly, although you won’t be able to get the presence of the user that way.

All of this assumes that the users have Lync running on their machine, i.e. assumes you won’t be opening chat up to users outside your organisation who may not have Lync installed.

Edit: Not having Lync installed changes things a lot. If Lync is installed, then Lync will handle setting up the audio call, and will handle the transfer of Audio between the participants in the conversation. Without Lync, you’d have to do that yourself, which won’t be straightforward.

Your best bet might be to have your users use the Lync Web App. This is a web based client that allows external users to join conferences. You’d need to build a UCMA 3.0 application which would sit inside your Lync infrastructure. The app would:

1. Accept a request from your web app to start a new conference, inviting the desired user – see here and here
2. When the conference is created, get the id and return it to the web user
3. In the web client, use the returned id to build a URL that opens the Lync Web App.

I can’t remember the syntax of the url off the top of my head, but to get it, you could create a new conference using the Lync Client, then select Invite By Email (from the icon of two “pawns”) – this will generate an email containing a URL – clicking the URL take you to a page that gives you conference join options, including installing the web app (you’d need to try the URL on a machine that doesn’t have Lync installed to get the option to install the web app)

Edit: My bad – the Lync Web App doesn’t support Audio. You could actually use the same concept as above, but with the Lync Attendee Client instead. However, this forces the user to install some components client side, so may not be acceptable in your scenario.

Edit: See also the answer here for more details, this refers to getting video to the client, but is relevant for audio too