Cisco Cisco Expressway

Introduction

This deployment guide describes how to configure a Cisco Collaboration video network to interwork with a Microsoft
environment, using the Microsoft Interoperability service on a dedicated Cisco Expressway ("Gateway" Expressway).

It also highlights the capabilities and limitations of interoperation between Expressway and Microsoft.

To enable video calling, screen sharing, messaging and presence between Cisco Unified Communications Manager-
registered collaboration endpoints and Microsoft clients, you need to configure:

■

A SIP trunk between the Gateway Expressway and Unified CM

■

The Microsoft Interoperability service on the Gateway Expressway to route calls to Microsoft

■

Static routes from Microsoft FE Servers to the Gateway Expressway

■

Static routes from Cisco Unified Communications Manager IM and Presence Service publishers to Microsoft
FE Servers

Deployment Scope

The following major Expressway-based deployments do not work together. They cannot be implemented together on
the same Expressway (or traversal pair):

■

Mobile and Remote Access

■

Microsoft Interoperability

■

Jabber Guest

■

Hybrid Services (connector host)

What is the Gateway Expressway and Why Should I Use It?

A Gateway Expressway is an Expressway-C (or cluster of Expressway-Cs) that provides interoperability between a
Cisco Collaboration network and the Microsoft environment.

We require that you dedicate an Expressway-C to this role so that you:

■

Minimize the impact of adding Microsoft interoperability to your existing Cisco Collaboration network.

■

Limit the number of Expressways that need the Microsoft Interoperability option key.

■

Reduce the number of static routes that you need to define from the Microsoft environment.

Each static route matches a single SIP domain to a single FQDN, or IP address, but you can create appropriate
DNS records to map an FQDN to a cluster of Expressways.

■

Reduce the number of third-party applications that you configure Microsoft to trust.

Microsoft FE Server will only accept SIP messages from peers that it trusts. By dedicating a Gateway
Expressway (or cluster), you reduce the number of trusted applications that you need to configure in
Microsoft.

Recommendations

■

We recommend that you use TLS connectivity throughout the deployment. We do not recommend
TCP because:

—

Microsoft SIP infrastructure uses TLS by default

—

TCP prevents the use of encryption

Cisco Expressway with Microsoft Infrastructure Deployment Guide

Introduction