mirror of https://github.com/asterisk/asterisk
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@401 65c4cc65-6c06-0410-ace0-fbb531ad65f31.0
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Inter-Asterisk eXchange Protocol
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||||
================================
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INTRODUCTION
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||||
------------
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||||
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This document is intended as an introduction to the Inter-Asterisk
|
||||
eXchange (or simply IAX) protocol. It provides both a theoretical
|
||||
background and practical information on its use.
|
||||
|
||||
WHY IAX
|
||||
-------
|
||||
The first question most people are thinking at this point is "Why do you
|
||||
need another VoIP protocol? Why didn't you just use SIP or H.323?"
|
||||
|
||||
Well, the answer is a fairly complicated one, but in a nutshell it's like
|
||||
this... Asterisk is intended as a very flexible and powerful
|
||||
communications tool. As such, the primary feature we need from a VoIP
|
||||
protocol is the ability to meet our own goals with Asterisk, and one with
|
||||
enough flexibility that we could use it as a kind of laboratory for
|
||||
inventing and implementing new concepts in the field. Neither H.323 or
|
||||
SIP fit the roles we needed, so we developed our own protocol, which,
|
||||
while not standards based, provides a number of advantages over both SIP
|
||||
and H.323, some of which are:
|
||||
|
||||
* Interoperability with NAT/PAT/Masquerade firewalls
|
||||
IAX seamlessly interoperates through all sorts of NAT and PAT
|
||||
and other firewalls, including the ability to place and
|
||||
receive calls, and transfer calls to other stations.
|
||||
|
||||
* High performance, low overhead protocol
|
||||
When running on low-bandwidth connections, or when running
|
||||
large numbers of calls, optimized bandwidth utilization is
|
||||
imperitive. IAX uses only 4 bytes of overhead
|
||||
|
||||
* Internationalization support
|
||||
IAX transmits language information, so that remote PBX
|
||||
content can be delivered in the native language of the
|
||||
calling party.
|
||||
|
||||
* Remote dialplan polling
|
||||
IAX allows a PBX or IP phone to poll the availability of a
|
||||
number from a remote server. This allows PBX dialplans to
|
||||
be centralized.
|
||||
|
||||
* Flexible authentication
|
||||
IAX supports cleartext, md5, and RSA authentication,
|
||||
providing flexible security models for outgoing calls and
|
||||
registration services.
|
||||
|
||||
* Multimedia protocol
|
||||
IAX supports the transmission of voice, video, images, text,
|
||||
HTML, DTMF, and URL's. Voice menus can be presented in both
|
||||
audibly and visually.
|
||||
|
||||
* Call statistic gathering
|
||||
IAX gathers statistics about network performance (including
|
||||
latency and jitter, as well as providing end-to-end latency
|
||||
measurement.
|
||||
|
||||
* Call parameter communication
|
||||
Caller*ID, requested extension, requested context, etc are
|
||||
all communicated through the call.
|
||||
|
||||
* Single socket design
|
||||
IAX's single socket design allows up to 32768 calls to be
|
||||
multiplexed.
|
||||
|
||||
While we value the importance of standards based (i.e. SIP) call handling,
|
||||
hopefully this will provide a reasonable explanation of why we developed
|
||||
IAX rather than starting with SIP.
|
||||
|
||||
CONFIG FILE CONVENTIONS
|
||||
-----------------------
|
||||
Lines beginning with '>' represent lines which might appear in an actual
|
||||
configuration file. The '>' is used to help separate them from the
|
||||
descriptive text and should not actually be included in the file itself.
|
||||
|
||||
Lines within []'s by themselves represent section labels within the
|
||||
configuration file. like this:
|
||||
|
||||
> [mysection]
|
||||
|
||||
Options are set using the "=" sign, for example
|
||||
|
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> myoption = value
|
||||
|
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Sometimes an option will have a number of discrete values which it can
|
||||
take. In that case, in the documentation, the options will be listed
|
||||
within square brackets (the "[" and "]" ones) separated by the pipe symbol
|
||||
("|"). For example:
|
||||
|
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> myoption = [value1|value2|value3]
|
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|
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means the option "myoption" can be assigned a value of "value1", "value2",
|
||||
or "value3".
|
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|
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Objects, or pseudo-objects are instantiated using the "=>" construct. For
|
||||
example:
|
||||
|
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> myobject => parameter
|
||||
|
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creates an object called "myobject" with some parameter whose definition
|
||||
would be specific to that object. Note that the config file parser
|
||||
considers "=>" and "=" to be equivalent and their use is purely to make
|
||||
configuration files more readable and easier to "humanly parse".
|
||||
|
||||
The comment character in Asterisk configuration files is the semicolon
|
||||
";". The reason it is not "#" is because the "#" symbol can be used as
|
||||
parts of extensions and it didn't seem like a good idea to have to escape
|
||||
it.
|
||||
|
||||
IAX CONFIGURATION IN ASTERISK
|
||||
-----------------------------
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|
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Like everything else in Asterisk, IAX's configuration lies in
|
||||
/etc/asterisk -- specifically /etc/asterisk/iax.conf
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|
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The IAX configuration file is a collection of sections, each of which
|
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(with the exception of the "general" section) represents an entity within
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the IAX scope.
|
||||
|
||||
------------
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|
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The first section is typically the "general" section. In this area,
|
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a number of parameters which affect the entire system are configured.
|
||||
Specifically, the default codecs, port and address, jitter behavior, TOS
|
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bits, and registrations.
|
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|
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The first line of the "general" section is always:
|
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|
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> [general]
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Following the first line are a number of other possibilities:
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> port = <portnum>
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This sets the port that IAX will bind to. The default IAX port number is
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5036. It is recommended that this value not be altered in general.
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> bindaddr = <ipaddr>
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This allows you to bind IAX to a specific local IP address instead of
|
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binding to all addresses. This could be used to enhance security if, for
|
||||
example, you only wanted IAX to be available to users on your LAN.
|
||||
|
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> bandwidth = [low|medium|high]
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|
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The bandwidth selection initializes the codec selection to appropriate
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values for given bandwidths. The "high" selection enables all codecs and
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is recommended only for 10Mbps or higher connections. The "medium"
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bandwidth eliminates signed linear, Mu-law and A-law codecs, leaving only
|
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the codecs which are 32kbps and smaller (with MP3 as a special case). It
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can be used with broadband connections if desired. "low" eliminates ADPCM
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and MP3 formats, leaving only the G.723.1, GSM, and LPC10.
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> allow = [gsm|lpc10|g723.1|adpcm|ulaw|alaw|mp3|slinear|all]
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> disallow = [gsm|lpc10|g723.1|adpcm|ulaw|alaw|mp3|slinear|all]
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The "allow" and "disallow" allow you to fine tune the codec selection
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beyond the initial bandwidth selection on a codec-by-codec basis.
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The recommended configuration is to select "low" bandwidth and then
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disallow the LPC10 codec just because it doesn't sound very good.
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> jitterbuffer = [yes|no]
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> dropcount = <dropamount>
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> maxjitterbuffer = <max>
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> maxexcessbuffer = <max>
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These parameters control the operation of the jitter buffer. The
|
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jitterbuffer should always be enabled unless you expect all your
|
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connections to be over a LAN. The drop count is the maximum number of
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voice packets to allow to drop (out of 100). Useful values are 3-10. The
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maxjitterbuffer is the maximum amount of jitter buffer to permit to be
|
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used. The "maxexcessbuffer" is the maximum amount of excess jitter buffer
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that is permitted before the jitter buffer is slowly shrunk to eliminate
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latency.
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> accountcode = <code>
|
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> amaflags = [default|omit|billing|documentation]
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These parameters affect call detail record generation. The first sets the
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account code for records received with IAX. The account code can be
|
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overridden on a per-user basis for incoming calls (see below). The
|
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amaflags controls how the record is labeled ("omit" causes no record to be
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written. "billing" and "documentation" label the records as billing or
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documentation records respectively, and "default" selects the system
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default.
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> tos = [lowdelay|throughput|reliability|mincost|none]
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IAX can optionally set the TOS (Type of Service) bits to specified values
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to help improve performance in routing. The recommended value is
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"lowdelay", which many routers (including any Linux routers with 2.4
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kernels that have not been altered with ip tables) will give priority to
|
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these packets, improving voice quality.
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> register => <name>[:<secret>]@<host>[:port]
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Any number of registery entries may be instantiated in the general
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section. Registration allows Asterisk to notify a remote Asterisk server
|
||||
(with a fixed address) what our current address is. In order for
|
||||
registration to work, the remote Asterisk server will need to have a
|
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dynamic peer entry with the same name (and secret if provided).
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The name is a required field, and is the remote peer name that we wish to
|
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identify ourselves as. A secret may be provided as well. The secret is
|
||||
generally a shared password between the local server and the remote
|
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server. However, if the secret is in square brackets ([]'s) then it is
|
||||
interpreted as the name of a key to use. In that case, the local Asterisk
|
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server must have the *private* key (/var/lib/asterisk/keys/<name>.key) and
|
||||
the remote server will have to have the corresponding public key.
|
||||
|
||||
The "host" is a required field and is the hostname or IP address of the
|
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remote Asterisk server. The port specification is optional and is by
|
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default 5036 if not specified.
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-------------
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The following sections, after "general" define either users, peers or
|
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friends. A "user" is someone who connects to us. A "peer" is someone
|
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that we connect to. A "friend" is simply shorthand for creating a "user"
|
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and "peer" with identical parameters (i.e. someone who can contact us and
|
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who we contact).
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||||
|
||||
> [identifier]
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The section begins with the identifier in square brackets. The identifier
|
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should be an alphanumeric string.
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||||
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> type = [user|peer|friend]
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This line tells Asterisk how to interpret this entity. Users are things
|
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that connect to us, while peers are people we connect to, and a friend is
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shorthand for creating a user and a peer with identical information
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||||
----------------
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User fields:
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> context = <context>
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||||
|
||||
One or more context lines may be specified in a user, thus giving the user
|
||||
access to place calls in the given contexts. Contexts are used by
|
||||
Asterisk to divide dialing plans into logical units each with the ability
|
||||
to have numbers interpreted differently, have their own security model,
|
||||
auxilliary switch handling, and include other contexts. Most users are
|
||||
given access to the default context. Trusted users could be given access
|
||||
to the local context for example.
|
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|
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> permit = <ipaddr>/<netmask>
|
||||
> deny = <ipaddr>/<netmask>
|
||||
|
||||
Permit and deny rules may be applied to users, allowing them to connect
|
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from certain IP addresses and not others. The permit and deny rules are
|
||||
interpreted in sequence and all are evaluated on a given IP address, with
|
||||
the final result being the decision. For example:
|
||||
|
||||
> permit = 0.0.0.0/0.0.0.0
|
||||
> deny = 192.168.0.0/255.255.255.0
|
||||
|
||||
would deny anyone in 192.168.0.0 with a netmask of 24 bits (class C),
|
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whereas:
|
||||
|
||||
> deny = 192.168.0.0/255.255.255.0
|
||||
> permit = 0.0.0.0/0.0.0.0
|
||||
|
||||
would not deny anyone since the final rule would permit anyone, thsu
|
||||
overriding the denial.
|
||||
|
||||
If no permit/deny rules are listed, it is assumed that someone may connect
|
||||
from anywhere.
|
||||
|
||||
> callerid = <callerid>
|
||||
|
||||
You may override the Caller*ID information passed by a user to you (if
|
||||
they choose to send it) in order that it always be accurate from the
|
||||
perspective of your server.
|
||||
|
||||
> auth = [md5|plaintext|rsa]
|
||||
|
||||
You may select which authentication methods are permitted to be used by
|
||||
the user to authenticate to us. Multiple methods may be specified,
|
||||
separated by commas. If md5 or plaintext authentication is selected, a
|
||||
secret must be provided. If RSA authentication is specified, then one or
|
||||
more key names must be specifed with "inkeys"
|
||||
|
||||
If no secret is specified and no authentication method is specified, then
|
||||
no authentication will be required.
|
||||
|
||||
> secret = <secret>
|
||||
|
||||
The "secret" line specifies the shared secret for md5 and plaintext
|
||||
authentication methods. It is never suggested to use plaintext except in
|
||||
some cases for debugging.
|
||||
|
||||
> inkeys = key1[:key2...]
|
||||
|
||||
The "inkeys" line specifies which keys we can use to authenticate the
|
||||
remote peer. If the peer's challenge passes with any of the given keys,
|
||||
then we accept its authentication. The key files live in
|
||||
/var/lib/asterisk/keys/<name>.pub and are *public keys*. Public keys are
|
||||
not typically DES3 encrypted and thus do not usually need initialization.
|
||||
|
||||
---------------
|
||||
Peer configuration
|
||||
|
||||
> allow = [gsm|lpc10|g723.1|adpcm|ulaw|alaw|mp3|slinear|all]
|
||||
> disallow = [gsm|lpc10|g723.1|adpcm|ulaw|alaw|mp3|slinear|all]
|
||||
|
||||
The "allow" and "disallow" may be used to enable or disable specific codec
|
||||
support on a per-peer basis.
|
||||
|
||||
> host = [<ipaddr>|dynamic]
|
||||
|
||||
The host line specifies the hostname or IP address of the remote host, or
|
||||
may be the word "dynamic" signifying that the host will register with us
|
||||
(see register => in the general section above).
|
||||
|
||||
> defaultip = <ipaddr>
|
||||
|
||||
If the host uses dynamic registration, Asterisk may still be given a
|
||||
default IP address to use when dynamic registration has not been performed
|
||||
or has timed out.
|
||||
|
||||
|
@ -0,0 +1,326 @@
|
||||
Inter-Asterisk eXchange Protocol
|
||||
================================
|
||||
|
||||
INTRODUCTION
|
||||
------------
|
||||
|
||||
This document is intended as an introduction to the Inter-Asterisk
|
||||
eXchange (or simply IAX) protocol. It provides both a theoretical
|
||||
background and practical information on its use.
|
||||
|
||||
WHY IAX
|
||||
-------
|
||||
The first question most people are thinking at this point is "Why do you
|
||||
need another VoIP protocol? Why didn't you just use SIP or H.323?"
|
||||
|
||||
Well, the answer is a fairly complicated one, but in a nutshell it's like
|
||||
this... Asterisk is intended as a very flexible and powerful
|
||||
communications tool. As such, the primary feature we need from a VoIP
|
||||
protocol is the ability to meet our own goals with Asterisk, and one with
|
||||
enough flexibility that we could use it as a kind of laboratory for
|
||||
inventing and implementing new concepts in the field. Neither H.323 or
|
||||
SIP fit the roles we needed, so we developed our own protocol, which,
|
||||
while not standards based, provides a number of advantages over both SIP
|
||||
and H.323, some of which are:
|
||||
|
||||
* Interoperability with NAT/PAT/Masquerade firewalls
|
||||
IAX seamlessly interoperates through all sorts of NAT and PAT
|
||||
and other firewalls, including the ability to place and
|
||||
receive calls, and transfer calls to other stations.
|
||||
|
||||
* High performance, low overhead protocol
|
||||
When running on low-bandwidth connections, or when running
|
||||
large numbers of calls, optimized bandwidth utilization is
|
||||
imperitive. IAX uses only 4 bytes of overhead
|
||||
|
||||
* Internationalization support
|
||||
IAX transmits language information, so that remote PBX
|
||||
content can be delivered in the native language of the
|
||||
calling party.
|
||||
|
||||
* Remote dialplan polling
|
||||
IAX allows a PBX or IP phone to poll the availability of a
|
||||
number from a remote server. This allows PBX dialplans to
|
||||
be centralized.
|
||||
|
||||
* Flexible authentication
|
||||
IAX supports cleartext, md5, and RSA authentication,
|
||||
providing flexible security models for outgoing calls and
|
||||
registration services.
|
||||
|
||||
* Multimedia protocol
|
||||
IAX supports the transmission of voice, video, images, text,
|
||||
HTML, DTMF, and URL's. Voice menus can be presented in both
|
||||
audibly and visually.
|
||||
|
||||
* Call statistic gathering
|
||||
IAX gathers statistics about network performance (including
|
||||
latency and jitter, as well as providing end-to-end latency
|
||||
measurement.
|
||||
|
||||
* Call parameter communication
|
||||
Caller*ID, requested extension, requested context, etc are
|
||||
all communicated through the call.
|
||||
|
||||
* Single socket design
|
||||
IAX's single socket design allows up to 32768 calls to be
|
||||
multiplexed.
|
||||
|
||||
While we value the importance of standards based (i.e. SIP) call handling,
|
||||
hopefully this will provide a reasonable explanation of why we developed
|
||||
IAX rather than starting with SIP.
|
||||
|
||||
CONFIG FILE CONVENTIONS
|
||||
-----------------------
|
||||
Lines beginning with '>' represent lines which might appear in an actual
|
||||
configuration file. The '>' is used to help separate them from the
|
||||
descriptive text and should not actually be included in the file itself.
|
||||
|
||||
Lines within []'s by themselves represent section labels within the
|
||||
configuration file. like this:
|
||||
|
||||
> [mysection]
|
||||
|
||||
Options are set using the "=" sign, for example
|
||||
|
||||
> myoption = value
|
||||
|
||||
Sometimes an option will have a number of discrete values which it can
|
||||
take. In that case, in the documentation, the options will be listed
|
||||
within square brackets (the "[" and "]" ones) separated by the pipe symbol
|
||||
("|"). For example:
|
||||
|
||||
> myoption = [value1|value2|value3]
|
||||
|
||||
means the option "myoption" can be assigned a value of "value1", "value2",
|
||||
or "value3".
|
||||
|
||||
Objects, or pseudo-objects are instantiated using the "=>" construct. For
|
||||
example:
|
||||
|
||||
> myobject => parameter
|
||||
|
||||
creates an object called "myobject" with some parameter whose definition
|
||||
would be specific to that object. Note that the config file parser
|
||||
considers "=>" and "=" to be equivalent and their use is purely to make
|
||||
configuration files more readable and easier to "humanly parse".
|
||||
|
||||
The comment character in Asterisk configuration files is the semicolon
|
||||
";". The reason it is not "#" is because the "#" symbol can be used as
|
||||
parts of extensions and it didn't seem like a good idea to have to escape
|
||||
it.
|
||||
|
||||
IAX CONFIGURATION IN ASTERISK
|
||||
-----------------------------
|
||||
|
||||
Like everything else in Asterisk, IAX's configuration lies in
|
||||
/etc/asterisk -- specifically /etc/asterisk/iax.conf
|
||||
|
||||
The IAX configuration file is a collection of sections, each of which
|
||||
(with the exception of the "general" section) represents an entity within
|
||||
the IAX scope.
|
||||
|
||||
------------
|
||||
|
||||
The first section is typically the "general" section. In this area,
|
||||
a number of parameters which affect the entire system are configured.
|
||||
Specifically, the default codecs, port and address, jitter behavior, TOS
|
||||
bits, and registrations.
|
||||
|
||||
The first line of the "general" section is always:
|
||||
|
||||
> [general]
|
||||
|
||||
Following the first line are a number of other possibilities:
|
||||
|
||||
> port = <portnum>
|
||||
|
||||
This sets the port that IAX will bind to. The default IAX port number is
|
||||
5036. It is recommended that this value not be altered in general.
|
||||
|
||||
> bindaddr = <ipaddr>
|
||||
|
||||
This allows you to bind IAX to a specific local IP address instead of
|
||||
binding to all addresses. This could be used to enhance security if, for
|
||||
example, you only wanted IAX to be available to users on your LAN.
|
||||
|
||||
> bandwidth = [low|medium|high]
|
||||
|
||||
The bandwidth selection initializes the codec selection to appropriate
|
||||
values for given bandwidths. The "high" selection enables all codecs and
|
||||
is recommended only for 10Mbps or higher connections. The "medium"
|
||||
bandwidth eliminates signed linear, Mu-law and A-law codecs, leaving only
|
||||
the codecs which are 32kbps and smaller (with MP3 as a special case). It
|
||||
can be used with broadband connections if desired. "low" eliminates ADPCM
|
||||
and MP3 formats, leaving only the G.723.1, GSM, and LPC10.
|
||||
|
||||
> allow = [gsm|lpc10|g723.1|adpcm|ulaw|alaw|mp3|slinear|all]
|
||||
> disallow = [gsm|lpc10|g723.1|adpcm|ulaw|alaw|mp3|slinear|all]
|
||||
|
||||
The "allow" and "disallow" allow you to fine tune the codec selection
|
||||
beyond the initial bandwidth selection on a codec-by-codec basis.
|
||||
|
||||
The recommended configuration is to select "low" bandwidth and then
|
||||
disallow the LPC10 codec just because it doesn't sound very good.
|
||||
|
||||
> jitterbuffer = [yes|no]
|
||||
> dropcount = <dropamount>
|
||||
> maxjitterbuffer = <max>
|
||||
> maxexcessbuffer = <max>
|
||||
|
||||
These parameters control the operation of the jitter buffer. The
|
||||
jitterbuffer should always be enabled unless you expect all your
|
||||
connections to be over a LAN. The drop count is the maximum number of
|
||||
voice packets to allow to drop (out of 100). Useful values are 3-10. The
|
||||
maxjitterbuffer is the maximum amount of jitter buffer to permit to be
|
||||
used. The "maxexcessbuffer" is the maximum amount of excess jitter buffer
|
||||
that is permitted before the jitter buffer is slowly shrunk to eliminate
|
||||
latency.
|
||||
|
||||
> accountcode = <code>
|
||||
> amaflags = [default|omit|billing|documentation]
|
||||
|
||||
These parameters affect call detail record generation. The first sets the
|
||||
account code for records received with IAX. The account code can be
|
||||
overridden on a per-user basis for incoming calls (see below). The
|
||||
amaflags controls how the record is labeled ("omit" causes no record to be
|
||||
written. "billing" and "documentation" label the records as billing or
|
||||
documentation records respectively, and "default" selects the system
|
||||
default.
|
||||
|
||||
> tos = [lowdelay|throughput|reliability|mincost|none]
|
||||
|
||||
IAX can optionally set the TOS (Type of Service) bits to specified values
|
||||
to help improve performance in routing. The recommended value is
|
||||
"lowdelay", which many routers (including any Linux routers with 2.4
|
||||
kernels that have not been altered with ip tables) will give priority to
|
||||
these packets, improving voice quality.
|
||||
|
||||
> register => <name>[:<secret>]@<host>[:port]
|
||||
|
||||
Any number of registery entries may be instantiated in the general
|
||||
section. Registration allows Asterisk to notify a remote Asterisk server
|
||||
(with a fixed address) what our current address is. In order for
|
||||
registration to work, the remote Asterisk server will need to have a
|
||||
dynamic peer entry with the same name (and secret if provided).
|
||||
|
||||
The name is a required field, and is the remote peer name that we wish to
|
||||
identify ourselves as. A secret may be provided as well. The secret is
|
||||
generally a shared password between the local server and the remote
|
||||
server. However, if the secret is in square brackets ([]'s) then it is
|
||||
interpreted as the name of a key to use. In that case, the local Asterisk
|
||||
server must have the *private* key (/var/lib/asterisk/keys/<name>.key) and
|
||||
the remote server will have to have the corresponding public key.
|
||||
|
||||
The "host" is a required field and is the hostname or IP address of the
|
||||
remote Asterisk server. The port specification is optional and is by
|
||||
default 5036 if not specified.
|
||||
|
||||
-------------
|
||||
|
||||
The following sections, after "general" define either users, peers or
|
||||
friends. A "user" is someone who connects to us. A "peer" is someone
|
||||
that we connect to. A "friend" is simply shorthand for creating a "user"
|
||||
and "peer" with identical parameters (i.e. someone who can contact us and
|
||||
who we contact).
|
||||
|
||||
> [identifier]
|
||||
|
||||
The section begins with the identifier in square brackets. The identifier
|
||||
should be an alphanumeric string.
|
||||
|
||||
> type = [user|peer|friend]
|
||||
|
||||
This line tells Asterisk how to interpret this entity. Users are things
|
||||
that connect to us, while peers are people we connect to, and a friend is
|
||||
shorthand for creating a user and a peer with identical information
|
||||
|
||||
----------------
|
||||
User fields:
|
||||
|
||||
> context = <context>
|
||||
|
||||
One or more context lines may be specified in a user, thus giving the user
|
||||
access to place calls in the given contexts. Contexts are used by
|
||||
Asterisk to divide dialing plans into logical units each with the ability
|
||||
to have numbers interpreted differently, have their own security model,
|
||||
auxilliary switch handling, and include other contexts. Most users are
|
||||
given access to the default context. Trusted users could be given access
|
||||
to the local context for example.
|
||||
|
||||
> permit = <ipaddr>/<netmask>
|
||||
> deny = <ipaddr>/<netmask>
|
||||
|
||||
Permit and deny rules may be applied to users, allowing them to connect
|
||||
from certain IP addresses and not others. The permit and deny rules are
|
||||
interpreted in sequence and all are evaluated on a given IP address, with
|
||||
the final result being the decision. For example:
|
||||
|
||||
> permit = 0.0.0.0/0.0.0.0
|
||||
> deny = 192.168.0.0/255.255.255.0
|
||||
|
||||
would deny anyone in 192.168.0.0 with a netmask of 24 bits (class C),
|
||||
whereas:
|
||||
|
||||
> deny = 192.168.0.0/255.255.255.0
|
||||
> permit = 0.0.0.0/0.0.0.0
|
||||
|
||||
would not deny anyone since the final rule would permit anyone, thsu
|
||||
overriding the denial.
|
||||
|
||||
If no permit/deny rules are listed, it is assumed that someone may connect
|
||||
from anywhere.
|
||||
|
||||
> callerid = <callerid>
|
||||
|
||||
You may override the Caller*ID information passed by a user to you (if
|
||||
they choose to send it) in order that it always be accurate from the
|
||||
perspective of your server.
|
||||
|
||||
> auth = [md5|plaintext|rsa]
|
||||
|
||||
You may select which authentication methods are permitted to be used by
|
||||
the user to authenticate to us. Multiple methods may be specified,
|
||||
separated by commas. If md5 or plaintext authentication is selected, a
|
||||
secret must be provided. If RSA authentication is specified, then one or
|
||||
more key names must be specifed with "inkeys"
|
||||
|
||||
If no secret is specified and no authentication method is specified, then
|
||||
no authentication will be required.
|
||||
|
||||
> secret = <secret>
|
||||
|
||||
The "secret" line specifies the shared secret for md5 and plaintext
|
||||
authentication methods. It is never suggested to use plaintext except in
|
||||
some cases for debugging.
|
||||
|
||||
> inkeys = key1[:key2...]
|
||||
|
||||
The "inkeys" line specifies which keys we can use to authenticate the
|
||||
remote peer. If the peer's challenge passes with any of the given keys,
|
||||
then we accept its authentication. The key files live in
|
||||
/var/lib/asterisk/keys/<name>.pub and are *public keys*. Public keys are
|
||||
not typically DES3 encrypted and thus do not usually need initialization.
|
||||
|
||||
---------------
|
||||
Peer configuration
|
||||
|
||||
> allow = [gsm|lpc10|g723.1|adpcm|ulaw|alaw|mp3|slinear|all]
|
||||
> disallow = [gsm|lpc10|g723.1|adpcm|ulaw|alaw|mp3|slinear|all]
|
||||
|
||||
The "allow" and "disallow" may be used to enable or disable specific codec
|
||||
support on a per-peer basis.
|
||||
|
||||
> host = [<ipaddr>|dynamic]
|
||||
|
||||
The host line specifies the hostname or IP address of the remote host, or
|
||||
may be the word "dynamic" signifying that the host will register with us
|
||||
(see register => in the general section above).
|
||||
|
||||
> defaultip = <ipaddr>
|
||||
|
||||
If the host uses dynamic registration, Asterisk may still be given a
|
||||
default IP address to use when dynamic registration has not been performed
|
||||
or has timed out.
|
||||
|
||||
|
Loading…
Reference in new issue