Snom phones, SIP proxy Frequently Asked Questions Manual
F REQUENTLY
A SKED
Q UESTION
How can I use Microsoft®
Messenger with snom
phones and the snom SIP
proxy?
Date: Aug-29-2002
Author: Dr. Christian Stredicke
Document: faq-02-08-29-cs
2 snom technology AG
[ F R E Q U E N T L Y A S K E D Q U E S T I O N ]
Microsoft Messenger 3
[ F R E Q U E N T L Y A S K E D Q U E S T I O N ]
About Microsoft Messenger
With its Windows XP operating system, Microsoft offers a new real time communication
platform, the MicrosoftMessenger. The Messenger is also available as an update to Windows
2000 clients. The messenger uses SIP as its underlying protocol and is compatible with other
equipment that uses SIP. In comparison to Netmeeting, the Messenger does not merely offer
telephony calls and video conferencing in an improved quality - it also adds instant messaging
and presence indication features. The Messenger uses UPnP to tunnel NAT. This means that
a DSL router not supporting UPnP stops SIP trafc owing between the Messenger and the
Internet. The MSN service that also comes with the Messenger solves the problem in a different
way, but uses a proprietary protocol.
Registering Messenger at the Proxy
The Messenger uses its own proprietary protocol by default. If you want to use it with
SIP, you need to open the options dialog and select the tab for the SIP account. First of all, you
need to select the “Communication Services” and then enter your SIP account at the bottom. In
order for the messenger to be able to nd the proxy, it is important that this name contains the
“@” symbol. The advanced button contains additional settings. The server address is not the
address of the proxy, but the address to which all packets should be sent. This is the “outbound
proxy”, which what can take care of NAT and other problems. The transport layer should be
set to UDP or to TCP, TLS is not supported by the snom proxy. The Messenger reports on the
success of the registration. You can also see in the proxy web page for the registered clients
that the new user is available.
Important: If the proxy challenges the user agent, the domain of the proxy must be set to
the domain that users are registering with. See the proxy manual for details.
Calling the Messenger
Calling the Messenger is as easy as calling any other user. Just type in the URL of the
messenger and accept the voice conversation on your PC. The Messenger does not support
supplementary services like transfer or call parking (except hold, which is supported by the
Messenger). Group picking is provided with the proxy so the Messenger can participate in
such a group. Making a call in the other direction is also easy. Just type in the complete URL
(including the “@” symbol) of the other party and accept the call.
Sending Messages
To send a message from the Messenger to the phone, you can select the respective action
from the Messenger menu. Just enter the URL of the other party (including the “@”) and press
the send button in the dialog. On the snom phone, the screen changes and you can read the
new message. Additional messages are stored “behind” the top message and become visible
when the top message is read.
With the current software version, it is not possible to send a message from the snom
phone to the Messenger.