Topic Last Modified: 2013-02-16

To configure your firewall for ports and protocols necessary to support public instant messaging connectivity, first note that SIP/MTLS/TCP 5061 is bidirectional to account for the ability of contacts in the public IM provider to contact Lync clients, or for Lync to contact public IM contacts.

Windows Live Messenger can participate in audio/video communications with Lync clients. This accounts for the very similar firewall port and protocol configuration that you would typically have on the firewall to support Lync clients as external users.

Important:
More than ever, Lync is a powerful tool for connecting across organizations and with individuals around the world. Federation with Windows Live Messenger requires no additional user/device licenses beyond the Lync Standard Client Access License (CAL). Skype federation will be added to this list, enabling Lync users to reach hundreds of millions of people with IM and voice. Federation with Messenger client contacts will officially end on March 15, 2013, except for mainland China. Skype will become the federation client for federated users who previously used Messenger.

Important:

More than ever, Lync is a powerful tool for connecting across organizations and with individuals around the world. Federation with Windows Live Messenger requires no additional user/device licenses beyond the Lync Standard Client Access License (CAL). Skype federation will be added to this list, enabling Lync users to reach hundreds of millions of people with IM and voice.

Federation with Messenger client contacts will officially end on March 15, 2013, except for mainland China. Skype will become the federation client for federated users who previously used Messenger.

Firewall Summary – Public Instant Messaging Connectivity

Role/Protocol/TCP or UDP/Port	Source IP address	Destination IP address	Notes
Access/SIP(MTLS)/TCP/5061	Public IM connectivity partners	Edge Server Access interface	For federated and public IM connectivity that use SIP.
Access/SIP(MTLS)/TCP/5061	Edge Server Access interface	Public IM connectivity partners	For federated and public IM connectivity that use SIP.
Access/SIP(TLS)/TCP/443	Clients	Edge Server Access interface	Client-to-server SIP traffic for external user access.
A/V/RTP/TCP/50,000-59,999	Edge Server Access interface	Live Messenger clients	Used for A/V sessions with Windows Live Messenger if public IM connectivity is configured.
A/V/STUN,MSTURN/UDP/3478	Edge Server Access interface	Live Messenger clients	Required for public IM connectivity with Windows Live Messenger.
A/V/STUN,MSTURN/UDP/3478	Live Messenger clients	Edge Server Access interface	Required for public IM connectivity with Windows Live Messenger.

Firewall Summary – Public Instant Messaging Connectivity

See Also