You can install Avaya IP Office Desktop Clients through group policy. This tutorial describes how to deploy a MSI on multiple machines using a group policy.

Ensure that the following are present on all the remote PCs:

.NET Framework 4.5.2
The install package for this can be downloaded from the Configure | Desktop Integration page within one-X Portal for IP Office.

.NET Framework 3.5
Support for .NET Framework 3.5 must also be enabled within the Windows Features on the user PC (from the Control Panel, select Programs and Features | Turn Windows features on or off).  

Microsoft Office 2007 PIA

Microsoft VSTO 2010 Runtime v4.0 (10.0.40303 or later)

Deployment Methods

Group policy supports two methods of deploying an MSI package:

Assign software
A program can be assigned per-user or per-machine. If it is assigned per-user, the program is installed when the user logs on. If it is assigned per-machine, the program is installed for all users when that machine starts.

Publish software
A published program is added to the Add or Remove Programs list and the user is able to install it from there.

Deployment Summary

1. Create a Distribution Point

2. Create a Group Policy Object

3. Assign an MSI Package

4. Publish an MSI Package

5. Redeploy an MSI Package

6. Remove an MSI Package

7. Silent Installation