Snom 4S Media Server Use and care manual

Administrator‘s
Manual
snom 4S
SIP Proxy/Registrar
Version 2.30

snom technology AG • 3
snom 4S Registrar Proxy Version 2.30 User Manual
© 2003 snom technology Aktiengesellschaft. All Rights Reserved.
This document is supplied by snom technology AG for information purposes only to licensed
users of the snom 4S registrar proxy and is supplied on an “AS IS” basis, that is, without any
warranties whatsoever, express or implied.
Information in this document is subject to change without notice and does not represent any
commitment on the part of snom technology AG. The software described in this document
is furnished under a license agreement and may be used only in accordance with the terms
of that license agreement. It is against the law to copy or use this software except as
specically allowed in the license. No part of this document may be reproduced, republished
or retransmitted in any form or by any means whatsoever, whether electronically or
mechanically, including, but not limited to, by way of photocopying, recording, information
recording or through retrieval systems, without the express written permission of snom
technology AG.

snom technology AG • 3
Welcome to the
SIP World!
SIP is becoming more and more accepted in the area of VoIP.
Many companies are working on SIP solutions and making great products
that will make telephony much easier and better.
SIP without a proxy makes no sense. Entering IP addresses to nd
another user cannot be the future of telephony. Locating http web content
and nding email users has become a part of todays communication
behavior and sure will be part of telephony in the near future.
snom 4S stands for “snom soft switch for small and medium
enterprises“. We started the work on this proxy with the goal to give
business a feature rich, robust and simple to use core component. Over
time, we found that it can also be used in other environments like Internet
telephony service provider. We added features that are necessary for
billing and worked on remote management support. If you set up a server
farm, you can create a robust solution that will continue operations even
under adverse conditions.
This product is a proxy/location server with built-in registrar
which means this software is also responsible for locating users. Needless
to say, the proxy is stateful, which means that is is capable of nding
users on a priority based schedule. However, for simplicity we call ist just
“proxy”.
Features like follow me and group calling are supported. As long
as the involved user agents support features, the proxy will he happy to
pass them through. That also includes instant messaging and presence
information. The proxy supports “store & forward”, when a user is not
logged in he or she may receive the message after loggin in. However
media services like mailbox and music on hold are not part of the software.
You should use a media server for this.
Interoperability is important to us. We have tried to stick to the
SIP standard as well as possible and tested the phones of other vendors.

4 • Welcome
[ S N O M 4S PR O X Y / R E G I S T R A R M ANUAL ]
snom technology AG • 5
We hope that this will help to build up a ourishing VoIP telephone
industry in which the products of the different vendors work together like
the products in the computer industry do today. We believe that having a
choice is good for you and therefore good for us.
This manual gives you a brief introduction to VoIP and SIP,
explains the installation process for Windows and Linux and shows how
to run the SIP proxy. For additional snom 4S information, please visit
our Web site at http://snom.com and if you have any comments and
suggestions about snom 4S, please contact us through snom technology
AG’s support link Web site. We would appreciate your feedback.
And, of course, you can reach us at sip:[email protected]
Thank you and have fun using the snom 4S!
Dr. Christian Stredicke Nicolas Peter-Pohland

4 • Welcome
[ S N O M 4S PR O X Y / R E G I S T R A R M ANUAL ]
snom technology AG • 5
Table of Contents
Welcome to the SIP World! ........................................3
Read This First ...........................................................9
Upgrades................................................................................... 9
Additional Information................................................................. 9
Scripting.................................................................................. 10
The Voice over Internet Protocol..............................11
Why SIP?................................................................................. 11
Open Standards ....................................................................... 12
What You Can Expect and What Not ............................................ 13
The SIP Architecture ................................................15
User Agents ............................................................................. 15
Proxies.................................................................................... 16
Location Server ........................................................................ 16
Registrars ................................................................................ 17
Media Server............................................................................ 17
Gateways ................................................................................ 17
B2BUA .................................................................................... 19
Installation ..............................................................21
Update to 2.30 from Previous Versions ........................................ 21
Windows Installation ................................................................. 23
Uninstalling in Windows ............................................................. 24
Linux Installation ...................................................................... 24
Manual Starting..................................................................................................................................................................................... 24
Automatic Starting ........................................................................................................................................................................... 25
Licensing ..................................................................27
Accessing the web server .......................................................... 27
Entering the license code ........................................................... 28

6 • Contents
[ S N O M 4S PR O X Y / R E G I S T R A R M ANUAL ]
snom technology AG • 7
[ S N O M 4S PR O X Y / R E G I S T R A R M ANUAL ]
Domains ...................................................................29
Deriving settings ...................................................................... 29
Creating a domain ................................................................... 30
Deleting a domain..................................................................... 31
Edit a domain........................................................................... 31
Going to a domain context ......................................................... 31
Backup ................................................................................... 32
Scripting...................................................................33
Background ............................................................................. 33
Script Structure........................................................................ 34
Quotes................................................................................................................................................................................................................ 34
Case....................................................................................................................................................................................................................... 35
Statements.............................................................................. 35
if.................................................................................................................................................................................................................................. 35
foreach............................................................................................................................................................................................................... 36
return................................................................................................................................................................................................................... 37
Variables ................................................................................. 37
Scope................................................................................................................................................................................................................... 37
Types.................................................................................................................................................................................................................... 37
Operators....................................................................................................................................................................................................... 38
Functions................................................................................. 39
Denition........................................................................................................................................................................................................ 39
Calling................................................................................................................................................................................................................. 40
String Functions ................................................................................................................................................................................... 40
Parsing Functions ............................................................................................................................................................................... 42
SIP functions............................................................................................................................................................................................. 44
Registration Related Functions....................................................................................................................................... 45
Proxy Related Functions........................................................................................................................................................... 46
Other Functions..................................................................................................................................................................................... 48
Callbacks................................................................................. 49
on_request................................................................................................................................................................................................... 49
on_response .............................................................................................................................................................................................. 51
on_register .................................................................................................................................................................................................. 52
challenge ........................................................................................................................................................................................................ 52
get_user .......................................................................................................................................................................................................... 54
on_new_user............................................................................................................................................................................................ 54
user_directory......................................................................................................................................................................................... 55
require_billing ......................................................................................................................................................................................... 56
on_denial........................................................................................................................................................................................................ 57

6 • Contents
[ S N O M 4S PR O X Y / R E G I S T R A R M ANUAL ]
snom technology AG • 7
[ S N O M 4S PR O X Y / R E G I S T R A R M ANUAL ]
on_unroutable......................................................................................................................................................................................... 58
General Setup...........................................................59
General Settings....................................................................... 59
SIP Port............................................................................................................................................................................................................. 59
STUN port...................................................................................................................................................................................................... 60
TCP threshold........................................................................................................................................................................................... 60
Log Level ........................................................................................................................................................................................................ 60
Log Filename............................................................................................................................................................................................. 60
HTTP port....................................................................................................................................................................................................... 61
HTTP User and Password......................................................................................................................................................... 61
Conguration in XML..................................................................................................................................................................... 61
User Accounts ..........................................................63
Purpose................................................................................... 63
Setting up accounts from the web interface.................................. 64
Uploading user accounts from le .............................................. 64
Storing information .................................................................. 65
Registration .............................................................67
Registration Settings ................................................................. 67
Require Authorization................................................................................................................................................................... 67
Min and Max registration time......................................................................................................................................... 68
Default Q ........................................................................................................................................................................................................ 68
Reject Registrations Across NAT .................................................................................................................................. 68
Example Registrations ............................................................... 69
Snom 200 .................................................................................................................................................................................................... 70
Microsoft Messenger .................................................................................................................................................................... 71
Routing ....................................................................73
Protected Destinations................................................................................................................................................................ 73
Max Forwards........................................................................................................................................................................................... 74
Call Log File ................................................................................................................................................................................................ 74
Tel Domain................................................................................................................................................................................................... 74
ENUM Sufx................................................................................................................................................................................................ 74
NAT Gateway............................................................................................................................................................................................ 74
Do not signal loose routing.................................................................................................................................................. 75
Do not Record-Route if Route is present.......................................................................................................... 75
Sequential Forking Time .......................................................................................................................................................... 76
Dial Plan.................................................................................. 77

8 • Contents
[ S N O M 4S PR O X Y / R E G I S T R A R M ANUAL ]
snom technology AG • 9
How it works.............................................................................................................................................................................................. 77
Example 1: Setting up overlap dialling............................................................................................................... 79
Example 2: North American Dial Plan .................................................................................................................. 80
Example 3: Do not allow cell phone numbers to certain users........................................ 80
Example 4: Using ENUM ............................................................ 81
Error-Information ..................................................................... 82
Message Handling ....................................................85
Store & Forward ....................................................................... 85
Welcome Message..................................................................... 85
DNS ..........................................................................87
What is DNS? ........................................................................... 87
Setup DNS............................................................................... 87
Server Farm Operation .............................................................. 89
ENUM...................................................................................... 90
Registering Phones ..................................................91
snom 100 Registration............................................................... 91
Microsoft Messenger Registration ................................................ 92
Maintenance.............................................................93
Registered Users ...................................................................... 93
Call Logs ................................................................................. 94
Condition for Logging a Call................................................................................................................................................ 94
Call Logs in the Web Interface........................................................................................................................................ 95
Pending Calls ............................................................................................................................................................................................ 96
Call Log File Format........................................................................................................................................................................ 96
SIP Message Flow ..................................................................... 97
Logging ................................................................................... 99
Index .....................................................................101

8 • Contents
[ S N O M 4S PR O X Y / R E G I S T R A R M ANUAL ]
snom technology AG • 9
Read This First
Before you read this manual please note the following three
important notes.
Upgrades
The 2.30 edition of the proxy does not require any additional
licenses. However, it is a major version update that could also carry the
name 3.0. In order not to confuse the licensing terms we chose the name
2.30.
The proxy keeps many of the proven concepts of the previous
versions, however introduces scripting and domains which makes it hard
for the installation process to automatically convert the conguration
data from the previous proxy versions into the new version. Some of the
settings need manual revision.
Therefore, if you update the proxy, we ask you to save old
conguration information for later reference. You can do this easily by
storing the web content of the relevant conguration pages to a le.
The installation process has been inproved especially for the
RedHat Linux edition and should now work smoothly on most systems.
That was especially on the 2.22 version one of the biggest problems for
installation.
Additional Information
This manual does not cover all topics that are related to the
usage of the proxy. We keep a list of frequently asked questions (FAQ) on
our website at http://snom.com/faq_en.php for specialized topics such as
remote management via shell script. They also contain topics that affect
other SIP components like the media server or the phones. These FAQ will
be kept up-do-date on a higher frequency than this proxy.

10 • Read This First
[ S N O M 4S PR O X Y / R E G I S T R A R M ANUAL ]
snom technology AG • 11
We also keep a list of bugxes in the Release Notes which is
available at the software download site at http://snom.com/down4s_
en.php. Before you make a software update, you make check this
document if the update is necessary or not.
Scripting
This version introduces “Scripting”. That means you may program
your proxy to exactly meet your requirements.
However, it is not a must. The default script takes the settings
from the web interface and allows the operation of the proxy that ts most
small and medium business requirements. So if you are not interested in
scripting you may skip the scripting chapter of this manual.