demanding;
What you need is Avaya Client Applications.
As per the installation guide blurb, this is a brief synopsis of what it is:
Lync Integration is intended for a network environment where the Microsoft Lync Server is deployed.
Lync Integration is a client side add-in to the Microsoft Lync 2010 and 2013 clients. Lync Integration
can be used to control an H.323 or SIP desk phone or a VDI Communicator client.
So no server required, and works with H.323 and SIP.
Basically you install the application onto each PC and configure the application to connect to the Aura system.
You then enter credentials for users station, define dial patterns etc...
Then you can place calls via Lync, using your deskphone/softphone as the voice path.
You will also see In a Call status for users also using the client etc...
See this document for requirements:
Note that access to software from Avaya may be on a licensed basis. Also full functionality will require certain CM licenses like IP Softphone and IP Video Softphone (depending what you want to do)
Thanks