Snom 4S Media Server Service manual

Administrator‘s
Guide
snom 4S
SIP Proxy/Registrar
Version 2.42

snom technology AG • 3
snom 4S Registrar Proxy Version 2.42 Administrator
Manual (2nd Ed.)
© 2001-2004 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.
Legal Disclaimer
snom offers the software described in this manual for both open source operating systems
as well as licensed operating systems. Whenever software that has been used under GPL
or LGPL licensing conditions has been used by this product you can download the sources
from http://www.snom.com/downlad/gpl/snom_ossdk or purchase a disc from snom for a
nominal fee under the ordering code snom SDK CD.

snom technology AG • 3
Table of Contents
1 Read This First ........................................................7
1.1 Software Updates.................................................................. 7
1.2 Additional Information ........................................................... 7
2 Installation..............................................................9
2.1 Update to 2.3x from 2.2x ....................................................... 9
2.2 Choosing Ports...................................................................... 9
2.3 Windows ........................................................................... 11
2.3.1 Installation................................................................................................................................................................................. 11
2.3.2 Uninstalling in Windows.......................................................................................................................................... 13
2.4 Linux Installation ................................................................ 13
2.4.1 Manual Starting.................................................................................................................................................................. 13
2.4.2 Automatic Starting......................................................................................................................................................... 13
2.4.3 Software Updates............................................................................................................................................................ 14
2.5 Accessing the web server ..................................................... 14
2.6 Licensing............................................................................ 15
2.7 DNS Setup ......................................................................... 17
2.7.1 DNS Example......................................................................................................................................................................... 17
3 General Setup........................................................19
3.1 IP Address Conguration ...................................................... 19
3.1.1 Binding to the right address............................................................................................................................. 19
3.1.2 Receiving forwarded packets .......................................................................................................................... 19
3.1.3 STUN Settings....................................................................................................................................................................... 21
3.2 Security Setup .................................................................... 22
3.2.1 https/http Access............................................................................................................................................................. 22
3.2.2 Administrator Access.................................................................................................................................................. 23
3.2.3 Importing Certicates................................................................................................................................................ 23
3.3 System Settings.................................................................. 25
3.3.1 Log Level...................................................................................................................................................................................... 25
3.3.2 Log Filename.......................................................................................................................................................................... 25
3.3.3 Internal Length ................................................................................................................................................................... 26
3.3.4 Cache Sizes .............................................................................................................................................................................. 26
3.3.5 Maximum Number of Subscriptions ...................................................................................................... 26

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3.3.6 Unavailable Host TTL.................................................................................................................................................. 26
3.3.7 Handle Dialog Subscriptions............................................................................................................................. 27
3.3.8 Act as Presence-Server........................................................................................................................................... 27
3.3.9 Perform Number Guessing ................................................................................................................................. 28
3.3.10 Loose Routing Flag..................................................................................................................................................... 28
3.3.11 Email Setup.......................................................................................................................................................................... 28
3.3.12 License Reporting ........................................................................................................................................................ 29
3.3.14 RADIUS Settings........................................................................................................................................................... 29
3.3.15 Conguration in XML............................................................................................................................................... 29
4 STUN .....................................................................31
4.1 Setting up STUN ................................................................. 31
4.2 128 Bit STUN...................................................................... 32
5 Domains ................................................................33
5.1 Deriving settings ................................................................. 33
5.2 Creating a domain .............................................................. 34
5.3 Deleting a domain ............................................................... 35
5.4 Edit a domain ..................................................................... 35
5.5 Going to a domain context.................................................... 35
5.6 Determining the Domain Context........................................... 35
5.6.1 Purpose........................................................................................................................................................................................... 35
5.6.2 Usage ................................................................................................................................................................................................ 36
5.7 Backup .............................................................................. 37
6 Server Farm ..........................................................39
6.1 Shutting servers down ......................................................... 39
6.2 Number of necessary servers ................................................ 39
6.3 DNS considerations ............................................................. 40
6.4 Refresh rate considerations................................................... 41
6.5 Settings ............................................................................. 41
7 Domain Settings ....................................................43
7.1 HTTP Interface.................................................................... 43
7.2 Conferencing and Call-back .................................................. 44
8 Accounts ...............................................................45
8.1 Purpose ............................................................................. 45
8.2 Setting up accounts from the web interface ............................ 46
8.3 Uploading user accounts from le .......................................... 47
8.3.1 Old Proxy Format............................................................................................................................................................. 47

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8.3.2 Importing Accounts from Spreadsheet Tools .......................................................................... 47
8.4 Storing information ............................................................. 49
8.5 Changing Normal User Settings ............................................. 49
8.5.1 Single Registration......................................................................................................................................................... 49
8.5.2 3rd Party Registration............................................................................................................................................... 50
8.5.3 User-Visible Settings................................................................................................................................................... 50
9 Automatic User Agent Conguration......................51
9.1 Server Detection ................................................................. 51
9.2 Setting Groups.................................................................... 52
9.3 MAC Addresses ................................................................... 53
9.4 Settings ............................................................................. 54
9.5 Software Version ................................................................. 55
10 Registration.........................................................57
10.1 Registration Settings.......................................................... 57
10.1.1 Require Authorization............................................................................................................................................ 57
10.1.2 Min and Max registration time .................................................................................................................. 57
10.1.3 Keep-Alive Registry Time................................................................................................................................. 58
10.1.4 Default Q.................................................................................................................................................................................. 58
10.1.5 Reject Registrations across NAT............................................................................................................. 58
11 Routing ...............................................................61
11.1 Domain Administrator Settings ............................................ 61
11.1.1 Protected Destinations ......................................................................................................................................... 61
11.1.2 Sequential Forking Time.................................................................................................................................... 62
11.2 System Administrator Settings ............................................ 63
11.2.1 Max Forwards .................................................................................................................................................................... 63
11.2.2 Tel Domain ............................................................................................................................................................................ 63
11.2.3 ENUM Sufx......................................................................................................................................................................... 64
11.2.4 Call Log File.......................................................................................................................................................................... 64
11.2.5 NAT Gateway...................................................................................................................................................................... 64
11.2.6 Route REGISTER, Route Other Requests................................................................................... 64
11.2.7 No Loose Routing......................................................................................................................................................... 65
11.2.8 Don’t Always Record-Route........................................................................................................................... 65
11.3 Dial Plan .......................................................................... 66
11.3.1 How it works....................................................................................................................................................................... 66
11.3.2 Call Pickup.............................................................................................................................................................................. 67
11.3.3 Example 1: North American Dial Plan............................................................................................ 68
11.3.4 Example 2: Do not allow cell phone numbers to certain users ................. 69
11.4 Error-Information .............................................................. 69

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12 Call Hunting.........................................................71
12.1 Dening Stages................................................................. 71
12.2 Dening the Algorithm ....................................................... 72
12.3 Default Actions.................................................................. 73
13 Address Books.....................................................75
13.1 Number Guessing .............................................................. 75
13.2 Dening Address Book Groups............................................. 75
13.3 Setting Up an Address Book................................................ 76
14 Controlling ..........................................................77
14.1 Dening Rates .................................................................. 77
14.2 Dening Groups ................................................................ 78
14.3 Controlling Data ................................................................ 78
15 Message Handling ...............................................81
15.1 Store & Forward ................................................................ 81
15.2 Welcome Message ............................................................. 81
16 Status Reports.....................................................83
16.1 Registered Users ............................................................... 83
16.2 Call Logs .......................................................................... 84
16.2.1 Condition for Logging a Call ......................................................................................................................... 84
16.2.2 Call Logs in the Web Interface.................................................................................................................. 85
16.2.3 Call Attempts...................................................................................................................................................................... 86
16.3 SIP Trace.......................................................................... 86
16.4 Logs ................................................................................ 87
16.5 Unavailable Hosts .............................................................. 88
16.6 Memory Usage .................................................................. 88
17 Billing..................................................................91
17.1 CDR Generation ................................................................ 91
17.1.1 Call Log File Format.................................................................................................................................................. 91
17.1.2 XML-Based format...................................................................................................................................................... 91
17.2 RADIUS............................................................................ 92
17.2.1 Authentication and Accounting................................................................................................................. 92
17.2.2 Setup ............................................................................................................................................................................................. 93
17.2.3 RADIUS Server........................................................................................................................................................................
93
17.2.4 Security...................................................................................................................................................................................... 94

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1 Read This First
Before you start using the proxy and continue with the rest of this
manual please read the following important notes.
1.1 Software Updates
The 2.3x edition of the proxy uses the same license keys as the
previous versions. However, because of the domain concept, the license
checking algorithm had to be changed and the new proxy now checks
the hostnames directly against the found IP address. Therefore, the
list of hostnames should now include the IP address of the host. If you
have problems with this, please contact mailto:[email protected], please
include the old license information. We will give you a new license key in
this case.
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 2.2x proxy versions into the new version. Some of the settings
need manual update.
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
downloading of XML-Files is described below).
You can always nd information about the changes at our web
site, http://snom.com/download/proxy-release-notes.pdf.
1.2 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
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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 manual.
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 may check this document
if the update is necessary or not.
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2 Installation
2.1 Update to 2.3x from 2.2x
Versions 2.3x introduces a domain concept which is not directly
compatible to the 2.2x versions. The conguration information is stored
in a central directory, along with all other conguration information. The
previous versions used a different approach.
All conguration information is now stored in an XML-based
format in the le system. This approach makes it easier to maintain the
software across the various platforms and allows you to use standard
tools to maintain the conguration data e.g. for backup or revision control.
The XML les can be retrieved via the web interface which simplies the
support for the product across the Internet.
Although much of the interface remains the same, the software
update process cannot automatically convert the old conguration
information into the new format. Therefore, it is necessary to enter the
conguration information up again.
In case that you use an extensive dial plan, we recommend taking
a look at the scripting interface as it solves problems with the table based
dial plan. However, for simple installations you can still use the dial plan.
2.2 Choosing Ports
The proxy uses a number of ports for its communication to the
outside world. The most important port for installation and conguration
is the http port. You need this port in order to access the proxy with a web
browser.
The default http port number is 80. This is a reasonable choice in
case that you are not running any other http services on that machine or
that users want to access the machine. If you choose another port, users
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always have to specify the complete address including the port number.
Unfortunately, Microsoft Internet Explorer expects the complete address
including the scheme in this case (http://proxy:1234), which makes it
inconvenient to access the proxy. Therefore, if possible you should use
port 80. Otherwise, we recommend linking the proxy with the company
web site, so that users can easily access the proxy with a click and set a
bookmark.
If the port 80 is occupied by other services, you can select any
other port. If the proxy also cannot allocate your specied port, it will
try port 5068 and the following ports. However, you should avoid the
situation that the proxy selects the port.
The SIP port for the proxy should be set 5060. You can specify
also any other port; however some SIP user agents expect the proxy to
use 5060 and you can avoid trouble by using another port.
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2.3 Windows
Important: If you are doing an update, you rst need to stop
and uninstall the old proxy (see below).
2.3.1 Installation
After double clicking on the setup executable, the installation
program starts up. Press “Next” to begin the installation.
At the beginning of the installation the setup program asks you
to accept the license conditions. Please read them carefully, and then
select the “accept” button and press “next” to accept the conditions. If
you decline, the installation will be aborted.
After accepting the license agreement, the next screen asks you
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to enter your personal information. Enter your name and the name of
your organization.
You can then select the location where the proxy les will be put.
The installation program proposes a reasonable location but if you want
to you can change it. After this, the installation asks you for the location
where the registration information will be put. This directory needs
write access and will contain the information for registered users. The
installation program proposes a location relative to the proxy installation
directory, but it might be useful to specify a different location for this, e.g.
a temporary directory. It is important that the directory exists; the proxy
will not create this directory.
In the next step you can select the installation type. We
recommend using the “typical” installation.
Before the installation nishes, you need to dene on which ports
the proxy will operate. This is important because otherwise it will be hard
for you to nd the right port.
After nishing the setup wizard, check that the proxy is running.
If you do not want to reboot your system (because it is running other
critical applications), you can also manually start the service in the
services section of the Windows control interface.
Check that the installation has been successful by checking the
Services window of Windows. Open the services Window and look for
“snom 4S SIP Proxy/Registrar”. The status should be “Started”. If this is
not the case you should invoke the proxy by selecting “start”. In this case,
we recommend rebooting the system to check if the proxy is starting
again after the reboot.
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After making sure the proxy is running, you should connect to
the proxy to a web browser. In order to do this, you can connect to the
address of the local computer (http://127.0.0.1:8080 if you are running
the web browser on the same machine). It is important that you connect
to the proxy via web browser, because that is the only way to control the
proxy. If you forgot the port number or the proxy grabbed another port,
you can use “netstat” to nd the proxy http port.
2.3.2 Uninstalling in Windows
To uninstall the proxy, rst stop it in the services window. Then
go to the Software Window and click on “remove” for snom 4S proxy
Server.
2.4 Linux Installation
The software runs under SuSE and Red Hat Linux; other Linux
versions like mandrake will also be able to run the proxy, but these
versions are not explicitly supported in the installation script. We strongly
recommend using one of the supported Linux distributions in order to
keep the proxy stable.
We currently offer four builts. We differentiate between RedHat
und SuSE and 9.0 (both RedHat and SuSE) and 8.0 or earlier operating
system versions.
2.4.1 Manual Starting
If you just want to try the proxy, it should be enough to start the
proxy manually. Load the tarball to a directory of your choice and start the
proxy with the command “proxy”. You can use the command line arguments
shown in the next chapter. You don‘t need to have root permissions to run
the proxy in this mode, normal user rights are enough.
2.4.2 Automatic Starting
If you want the proxy to be started automatically after a reboot,
you need to set up some les as superuser. Make sure that you are logged
in as root and go to the directory where you want to put the proxy. This
directory will have subdirectories for the different proxy versions and for
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registrations. It typically also contains the conguration information.
su -
cd /usr/local
tar xvfz ~/snom_sip_proxy-i386-suse8-2.42.tgz
Go to the directory where you extracted the new version:
cd snom_sip_proxy-i386-suse8-2.42
The tarball includes a shell script with the name install.sh which
sets up the necessary les and links for you:
./install-suse8.sh
In the le /etc/rc.cong (for SuSE Linux) and /etc/init.d/functions
(for RedHat) the variables “START_SIP_PROXY” and “SIP_PROXY_OPTS”
are set to a value depending on the html port that you specify. You may
edit the le and modify the value.
The installation script for SuSE will install a command
rcsnomproxy. “rcsnomproxy start” starts the proxy while “rcsnomproxy
stop” terminates the proxy process. For RedHat, you can use the Service
Manager to control the proxy.
After the installation you should see that the proxy is running.
Open a web browser to see if the proxy is up and running. Reboot the
system and check whether the sip proxy was started automatically after
the reboot. You can then continue with the installation using the web
browser. Stop and restart the proxy with the rcsnomproxy command (in
SuSE) to check whether the conguration has been saved. In RedHat, use
the service command to control the proxy.
2.4.3 Software Updates
To update a version, copy the latest tarball into the directory and
run the install script of the new version. It will automatically shut down
the old proxy and run the new one. This takes less than a second and all
registered users will be still registered. However, ongoing calls will not be
billed during this update period.
2.5 Accessing the web server
Open a web browser and enter the http address of the proxy.
If the browser is running on the same host as a proxy, you may use
the address “127.0.0.1”. If you did not enter port 80, you also need to
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append the port number to that address, separated by a colon. Many web
browsers need to have the resource identier in front of this address like
“http://127.0.0.1:5068”. If you did not enter a valid port (for example
because the port is already occupied) the proxy will try ports 5068 and the
following ports. You might have to try these ports in order to get access to
the proxy. In this case you should dene the port number explicitly later
in order to avoid future confusion.
You will then see the login page of the proxy. The default user
name and password are “admin” with no password. Please enter this and
push the login button.
You will see that the proxy opens a session for you. The session
identier is always kept with all the links that you used during your
interaction with the proxy. The session is automatically deleted when you
don‘t use the proxy for more than one hour. To delete the session, click
the logout link.
The proxy offers links in the left frame for easy navigation. There
are different menus for administrator mode, domain administrator mode
and user mode.
2.6 Licensing
There are a number of license modes available for the proxy.
When you downloaded the proxy from the Internet, you will probably
have a demonstration license key. This license key is valid independently
from the host names that you enter. However it will become invalid after
the indicated date. Please notice that it is not possible to overwrite the
demonstration license key with another demonstration license key. The
following table shows the currently available license codes. A “registration”
is an account which has one or more contacts registered (for example,
one VoIP phone and one mailbox count as one registration if they are
using the same account).
Name Code Registrations Call Log
SME sme 50 100
sm1 100 100
sm2 200 100
Entry ent 10 10
en2 20 10
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Expert exp 500 100
ex1 1,000 100
ex2 2,000 100
ex5 5,000 100
exa 10,000 100
exb 20,000 100
exc 50,000 100
exd 100,000 100
When you buy the proxy from snom, you will receive a license
key. This license key depends on the host names that you enter in the
rst eld. The „Hostnames“ eld has a function to uniquely identify this
copy of the snom SIP proxy. Therefore, when requesting the license key
from snom you should use the DNS names of the host which will run
the proxy. You should also include the IP address of this host. Examples
are „proxy.mycompany.com 213.43.34.12“ or „sip.mycompany.com
mycompany.net 32.43.12.32“. Please always use fully qualied DNS
names including dots. When you are using private addresses, please also
specify a fully qualied DNS name so that snom can clearly identify the
copy of the SIP proxy.
To see the possible license types please refer to the data sheet.
After entering the license code, you can see the administration menu of
the SIP proxy.
In case you have trouble licensing the proxy, please contact your
reseller and provide the host names that you intend to license the proxy
to.
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2.7 DNS Setup
After you set up the proxy, you need to make sure it can be
found. Depending on the sophistication of your installation, you need to
set up some DNS entries. This manual does not describe how you change
the DNS entries; for this purpose, please consult the manual of the DNS
tool that you are using.
As long as you are using plain IP Version 4 addresses, you
don’t need to change anything with DNS. This might be appropriate
in a completely private network with only one proxy server at a xed
address.
SIP uses several DNS levels. The rst level is called NAPTR and
this is a way to determine on a exible way where a service can be found.
ENUM is built upon this level. If you want to locate your proxy using
ENUM, you will probably need the support of additional tools. DNS SRV
is a way to specify addresses for a specic service. Using this level, you
can specify several servers for one address. This enables redundancy and
scalability. DNS SRV is also a way to specify other port numbers than
the default port number for a service. DNS A is the simple DNS address
resolution mechanism we know from the old days that resolves exactly
one address.
We recommend setting up DNS SRV so that you can redirect the
SIP services to a different host than your main server. This way, you can
use the same email addresses for a user as the sip address.
2.7.1 DNS Example
To use the DNS SRV support, you need to dene entries for “_sip._
udp” and “_sip._tcp” for your domain and assign weights and probabilities
to the different hosts that serve these services. A conguration le for
Linux might look like this:
$TTL 1D
anycom.de. IN SOA fox.anycom.de. hostmaster.anycom.de. (
2002050111 ; serial
1D ; refresh
2H ; retry
1W ; expiry
1D ) ; minimum
IN NS fox
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IN NS ns2.anycomns.de.
MX 10 mail.anycom.de.
_sip._tcp.anycom.de. IN SRV 0 5 5060 sip-server.anycom.de.
IN SRV 0 1 5060 test.anycom.de.
IN SRV 1 5 5060 www.anycom.de.
_sip._udp.anycom.de. IN SRV 0 5 5060 sip-server.anycom.de.
IN SRV 0 1 5060 test.anycom.de.
IN SRV 1 5 5060 www.anycom.de.
_stun._udp.anycom.de. IN SRV 0 5 3478 sip-server.anycom.de.
localhost IN A 127.0.0.1
ns IN A 232.145.142.95
anycom.de. IN A 232.145.142.95
sip IN A 232.145.142.97
In this example, there are three choices for accessing the proxies
for anycom.de. The rst two, (sip-server.anycom.de and test.anycom.de)
have the weight 0, and as long as one of them is up they will be contacted.
Only if both of them are down, will the service go to www.anycom.de. The
probability of contacting sip-server is 5/6, the probability of contacting
1/6, as the preference sum is 6. That means that most of the load goes
to sip-server.
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3 General Setup
3.1 IP Address Conguration
The proxy offers a powerful way of conguring the IP identity of
the proxy. Normally, you don’t have to do any changes on this conguration
web site. However, when you are using the proxy on a device that has
more than one IP address or in a DMZ, this page can help solving your
problems.
In principle, the proxy needs to address two different issues
for each port. The rst question is on which IP address it should bind
the port; the second is what identity it should show (for example when
sending a SIP packet).
3.1.1 Binding to the right address
To help selecting the IP address where to bind to, the proxy will
search your host for IP addresses and show them in the pull down menu.
If you explicitly select them, the proxy will use them. If you choose
“Default Address”, the proxy will search a public address and if there is no
public address get a private address. If you select “Public Address”, the
proxy will select only a public address; if you select “Private Address”, the
proxy will select only a private address. “Public Address 2” will select the
second public address, which is helpful for automatic setup of the change-
IP port for STUN.
You can also put manually addresses on the list of available
addresses. There are two elds at the bottom of the page where you may
specify them. These addresses will also be offered in the pull down menu
as if they had been found on the host.
3.1.2 Receiving forwarded packets
If you forward packets to the proxy from a rewall or NAT, the
3.

20 • General Setup
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proxy needs to act as if it was using this address. If you are doing this, you
need to specify which address the proxy should use. The default selection
is “Bind Address” which means that the proxy is using the address which it
bound to. If you want to use something else than bind address, you must
specify which port the proxy should assume.
If you choose to operate the proxy in a DMZ, you should make
sure that the proxy can be reached both from private as well as from
public addresses via the address which you have specied. Sometimes
this is not possible with NAT equipment which forwards packets only
between public Internet and the private network.
3.