8.4 หัวข้อ [RasSrv::GWRewriteE164]

This section describes rewriting the dialedDigits E.164 number depending on the gateway a call has come from or is being sent to. This allows for more flexible manipulation of the dialedDigits for routing etc. In combination with the RasSrv::RewriteE164 you can have triple stage rewriting:


Call from "gw1", dialedDigits 0867822
|
|
V
Input rules for "gw1", dialedDigits now 550867822
|
|
V
Global rules, dialedDigits now 440867822
|
|
V
Gateway selection, dialedDigits now 440867822, outbound gateway "gw2"
|
|
V
Output rules for "gw2", dialedDigits now 0867822
|
|
V
Call to "gw2", dialedDigits 0867822


Format:
gw-alias=in|out=[!]original-prefix=target-prefix[;in|out...]

If the call matches the gateway, the direction and begins with original-prefix it is rewritten to target-prefix. If the `!' flag precedes the original-prefix, the sense is inverted. Special wildcard characters ('.' and '%') are available. Multiple rules for the same gateway should be separated by ';'.

Example:
gw1=in=123=321

If a call is received from "gw1" to 12377897, it is rewritten to 32177897 before further action is taken.

8.5 หัวข้อ [EndPoint::RewriteE164]

Once you specify prefix(es) for your gatekeeper endpoint, the parent gatekeeper will route calls with dialedDigits beginning with that prefixes. The child gatekeeper can rewrite the destination according to the rules specified in this section. By contrast, when an internal endpoint calls an endpoint registered to the parent gatekeeper, the source will be rewritten reversely.


Format:
external prefix=internal prefix

For example, if you have the following configuration,


[Parent GK]
ID=MasterGK
/ \
/ \
/ \
/ \
[Child GK] [EP3]
ID=ProxyGK E164=18888200
Prefix=188886
/ \
/ \
/ \
[EP1] [EP2]
E164=601 E164=602

With this rule:

188886=6

When EP1 calls EP3 by 18888200, the CallingPartyNumber in the Q.931 Setup will be rewritten to 18888601. Conversely, EP3 can reach EP1 and EP2 by calling 18888601 and 18888602, respectively. In consequence, an endpoint registered to the child gatekeeper with prefix '6' will appear as an endpoint with prefix '188886', for endpoints registered to the parent gatekeeper.

The section does not relate to the section RasSrv::RewriteE164, though the latter will take effect first.

8.6 หัวข้อ [Routing::Sql]

Rewrite the called alias with a SQL query. Supports routing OnARQ, OnLRQ and OnSetup.

If the string returned from the database is 'REJECT' (upper or lower case), the call is rejected. If the string matches a dotted IP address, it is taken as destination IP otherwise it is treated as a new destination alias. If 2 columns are returned, the first is treated as the new destination alias and the second is treated as new destination IP.

If multiple rows of destination IPs are returned they are used as alternative routes for failover and GnuGk will try them in order.

When at least one destination IP is specified or the call is rejected, the SQL policy will end the routing chain. If only the alias is changed, the chain continues with this updated alias.

When rejecting a call, the 2nd column can contain an integer designating the reject reason (H.225 AdmissionRejectReason for registered calls, H.225 LocationRejectReason for neighbor calls, H.225 disconnect reason for unregistered calls).

If the database returns nothing, the call is passed on unchanged.


Driver=MySQL | PostgreSQL | Firebird | ODBC | SQLite
Default: N/A

SQL database driver to use. Currently, MySQL, PostgreSQL, Firebird, ODBC and SQLite drivers are implemented.


Host=DNS[:PORT] | IP[:PORT]
Default: localhost

SQL server host address. Can be in the form of DNS[:PORT] or IP[:PORT]. Like sql.mycompany.com or sql.mycompany.com:3306 or 192.168.3.100.


Database=gnugk
Default: N/A

The database name to connect to.


Username=gnugk

The username used to connect to the database.


Password=secret

The password used to connect to the database. If the password is not specified, a database connection attempt without any password will be made.


Query=SELECT ...
Default: N/A

Define a SQL query to fetch the new destination number. The query is parameterized - that means parameter replacement is made before each query is executed. The following parameters are defined:

%c - the called alias
%p - the called IP (only available on Setup, empty otherwise)
%s - the calling IP
%r - the calling aliases
%{Calling-Station-Id} - the calling station ID (same value as used in accounting and authentication events)
%i - the call ID
%m - the message type (ARQ, LRQ or Setup)
Some of these can be empty if they aren't included in the ARQ, LRQ or Setup message.
If the query returns no rows, the current alias is used. Otherwise, the first result row is used.

Query string examples. Note that these are examples; the actual structure and schema are user defined, as are the various field names in these examples. GnuGk is simply expecting either IP addresses or aliases as a result of the query.


SELECT destination FROM routes WHERE called = '%c'
SELECT concat(prefix,'%c') FROM routes WHERE prefix = LEFT('%c', 5)
SELECT gatewayip FROM routes WHERE prefix = LEFT('%c',5)
SELECT concat(prefix,'%c'), gatewayip FROM routes WHERE route = LEFT('%c', 5) limit 3

8.7 หัวข้อ [Routing::NumberAnalysis]

This section defines rules for the numberanalysis routing policy. The policy checks a dialed number for minimum and/or maximum number of digits and sends ARJ, if necessary (number of digits is out of range), to support overlapped digit sending. It also partially supports Setup messages (no overlapped sending - only number length validation).


Format:
prefix=MIN_DIGITS[:MAX_DIGITS]

If the number matches the prefix, it is verified to consist of at least MIN_DIGITS digits and (if MAX_DIGITS is present) at most MAX_DIGITS digits. Special wildcard characters (!, '.' and '%') are available. If the number is too short, an ARJ is send with rejectReason set to incompleteAddress. If the number is too long, an ARJ is send with rejectReason set to undefinedReason. Prefix list is searched from the longest to the shortest prefix for a match. For Setup messages, a Release Complete with "badFormatAddress" is sent when the number has an incorrect length.


Example:

[RoutingPolicy::OnARQ]
default=numberanalysis,internal

[Routing::NumberAnalysis]
0048=12
48=10
.=6:20

Calls to destinations starting with 0048 require at least 12 digits, to 48 we require 10 digits and to all other destinations at least 6 and at most 20 digits.

8.8 หัวข้อ [Routing::CatchAll]

CatchAllIP=1.2.3.4
Default: (empty)

Specify an IP address to route all calls to. This overrides CatchAllAlias.


CatchAllAlias=Frank
Default: catchall

If CatchAllIP is not specified, then route all calls to this alias.

8.9 หัวข้อ [RewriteCLI]

This section contains a set of rewrite rules for ANI/CLI/H.323_ID numbers (Caller ID). The rewrite process is done in two stages - inbound rewrite and outbound rewrite. The inbound rewrite is done before any other Q.931 Setup message processing (such as inbound GWRewrite, authentication, accounting, ...), and because it alters the Calling-Station-Id it will have an effect in the authorization and accounting modules. The outbound rewrite takes place just before the Setup message is to be forwarded and its effect is visible only to the callee.

An inbound rewrite rule can be matched by a caller's IP and a dialed number or an original CLI/ANI. An outbound rewrite rule can be matched by a caller's IP, callee's IP and a dialed number or a destination number (the dialed number after rewrite) or a CLI/ANI (after inbound rewrite).

This module also provides CLIR (Calling Line Identification Restriction) feature that can be configured for each endpoint (rule).


ProcessSourceAddress=1
Default: 1

In addition to rewriting a Calling-Party-Number Information Element ("IE"), the sourceAddress element of a H.225.0 Setup message can be rewritten, so both contain consistent information.


RemoveH323Id=1
Default: 1

When a sourceInfo element of an H.225.0 Setup message is rewritten, aliases of type H323_ID, email_ID and url_ID can be left untouched if this option is disabled.


CLIRPolicy=apply
Default: N/A

A global Presentation Indicator ("PI") processing policy can be set up. This policy will be applied to all CLI rewrite rules that do not override it. Possible choices are forward - just forward the received PI as-is, apply - examine the received PI and hide CLI if it is set to "presentation restricted" and applyforterminals - similar to apply except that the number is removed only when the call is sent to a terminal, not a gateway.



Format for an inbound rule:
in:CALLER_IP=[pi=[allow|restrict][,forward|apply|applyforterminals]] [cli:|dno:]number_prefix(=|*=|~=|^=|/=)NEW_CLI[,NEW_CLI]...

The in: prefix tells that this is an inbound rule and the CALLER_IP will be used to match the rule (it can be a single IP or an entire subnet).


The optional pi= parameter controls CLIR (Calling Line Identification Restriction) features. Specifying either allow or restrict forces presentation indicator to be set to "presentation allowed" or "presentation restricted". forward, apply and applyforterminals controls how the received (if any) presentation indicator is processed by the gatekeeper. forward means forward it to the callee as-is, apply means hiding CLI if the PI is set to "presentation restricted", applyforterminals is similar to apply, except that CLI is hidden only when sending the call to a terminal, not a gateway.


The prefix cli: or dno: (the default) selects what number will be used to match the number_prefix - a caller id (CLI/ANI) or a dialed number. Number matching/rewriting can be done in five ways:

= - a cli or dno number will be matched using a prefix match against number_prefix and, if the match is found, CLI will be replaced with NEW_CLI.
~= - a cli or dno number will be matched using an identity match against number_prefix and, if both numbers are the same, CLI will be replaced with NEW_CLI.
*= - (VALID ONLY FOR cli) a cli number will be matched using a prefix match against number_prefix and, if the match is found, the matched CLI prefix (number_prefix) will be replaced with a NEW_CLI prefix.
^= - a cli or dno number will be matched using a prefix match against number_prefix and, if the match is found, H.323_ID will be replaced with NEW_CLI, Calling-Station-Id will remain unchanged.
/= - a cli or dno number will be matched using an identity match against number_prefix and, if both numbers are the same, H.323_ID will be replaced with NEW_CLI, Calling-Station=Id will remain unchanged,
After the equality (=/ =/*=/^=//=) sign, there follows a list of new CLI values to be used. If more than one value is specified, one will be chosen on a random basis. It's possible to specify whole number ranges, like 49173600000-49173699999 (for number ranges CLIs should have a fixed length). There is a special string constant "any", that can be used in place of the CALLER_IP or the number_prefix. To enable CLIR for this rule, use a special string constant "hide" instead of the list of new CLI values. Note that CLIR is far more useful for outbound rules.

Example 1:

[RewriteCLI]
in:192.168.1.1=dno:5551=3003
in:192.168.1.1=cli:1001=2222
in:192.168.1.1=any=1111

These rules state that for calls from the IP 192.168.1.1: 1) if the user dialed a number beginning with 5551, set CLI to 3003, 2) if the call is from user with CLI beginning with 1001, set CLI to 2222, 3) for other calls from this IP, set CLI to 1111.


Example 2:

[RewriteCLI]
in:192.168.1.0/24=any=18001111
in:192.168.2.0/24=any=18002222
in:any=any=0

These rules state that: 1) for calls from the network 192.168.1.0/24, set CLI to 18001111, 2) for calls from the network 192.168.2.0/24, set CLI to 18002222, 3) for other calls, set CLI to 0.


Example 3:

[RewriteCLI]
in:192.168.1.0/24=0048*=48
in:192.168.1.0/24=0*=48
in:any=100.~=48900900900

These rules state that: 1) for calls from the network 192.168.1.0/24, rewrite 0048 to 48 (example - 0048900900900 => 48900900900), 2) for other calls from the network 192.168.1.0/24, rewrite 0 to 48 (example - 0900900900 => 48900900900), 3) for other calls, if CLI is 4 digits and starts with 100, set it to 48900900900.


Example 4 (CLIR):

[RewriteCLI]
in:192.168.1.0/24=any=hide

This example causes caller's number to be removed from Setup messages originating from the 192.168.1.0/24 network. It also causes proper presentation and screening indicators to be set in Setup messages.


Format for an outbound rule:
out:CALLER_IP=CALLEE_IP [pi=[allow|restrict][,forward|apply|applyforterminals]] [cli:|dno:|cno:]number_prefix(=|~=|*=)NEW_CLI[,NEW_CLI]...

The out: prefix tells that this is an outbound rule, the CALLER_IP and the CALLEE_IP will be used to match the rule and can be a single IP or a subnet address.


The optional pi= parameter controls CLIR (Calling Line Identification Restriction) features. Specifying either allow or restrict forces the presentation indicator to be set to "presentation allowed" or "presentation restricted". forward, apply and applyforterminals controls how the received (if any) presentation indicator is processed by the gatekeeper. forward means just to forward it to the callee as-is, apply means hiding CLI if the PI is set to "presentation restricted", applyforterminals is similar to apply, except that the CLI is hidden only when sending the call to a terminal, not a gateway.


The prefix cli:, dno: (the default) or cno: selects what number will be used to match the number_prefix - a caller id (CLI/ANI), a dialed number or a destination/called number (the dialed number after rewrite). Number matching/rewriting can be done in three ways:

= - a cli or dno number will be matched using a prefix match against number_prefix and, if the match is found, CLI will be replaced with NEW_CLI,
~= - a cli or dno number will be matched using an identity match against number_prefix and, if both numbers are the same, CLI will be replaced with NEW_CLI,
*= - (VALID ONLY FOR cli) a cli number will be matched using a prefix match against number_prefix and, if the match is found, the matched CLI prefix (number_prefix) will be replaced with a NEW_CLI prefix.
After the equality sign (=/ =/*=), a list of new CLI values to be used is specified. If more than one value is configured, one will be chosen on a random basis. It's possible to specify entire number ranges, like 49173600000-49173699999. There is a special string constant "any" which can be used in place of the CALLER_IP, the CALLEE_IP or the number_prefix. To enable CLIR for this rule, use a special string constant "hide" or "hidefromterminals" instead of the list of new CLI values.

Example 1:

[RewriteCLI]
out:any=192.168.1.1 any=1001
out:any=192.168.1.2 any=1002

These rules set a fixed ANI/CLI for each terminating IP: 1) present myself with ANI 1001, when sending calls to IP 192.168.1.1, 2) present myself with ANI 1002, when sending calls to IP 192.168.1.2.


Example 2:

[RewriteCLI]
out:any=192.168.1.1 any=1001-1999,3001-3999

This rule randomly selects ANI/CLI from range 1001-1999, 3001-3999 for calls sent to 192.168.1.1.


Example 3 (CLIR):

[RewriteCLI]
out:any=any any=hidefromterminals
out:192.168.1.1=any any=hide

In this example each subscriber has enabled CLIR, so all calls to terminals will have a caller's number removed and presentation/screening indicators set. Calls to gateways will have the presentation indicator set to "presentation restricted" and the caller's number will not be removed to allow proper call routing and number removal at the destination equipment.
One exception to these rules are calls from 192.168.1.1 which will have a caller's number always removed, no matter whether calling a terminal or a gateway.


Example 4 (CLIP):

[RewriteCLI]
out:any=192.168.1.1 any=hide

In this example CLIP (Calling Line Identification Presentation) feature is disabled for the user 192.168.1.1.


Example 5 (CLIR):

[RewriteCLI]
out:192.168.1.1=any pi=restrict,apply cli:.*=.
out:any=any pi=allow cli:.*=.

These rules do not change CLI (.*=.) and: 1) enable CLIR for an endpoint 192.168.1.1. apply tells the gatekeeper to not only set the PI, but also to hide the number. 2) force CLI presentation for other endpoints.


The rule matching process has a strictly defined order:

the closest caller's IP match is determined (closest means with the longest network mask - single IPs have the highest priority, "any" has the lowest priority),
(outbound rules) the closest callee's IP match is determined,
the longest matching prefix/number is searched for the given IP/IP pair in the following order:
dno: type (dialed number) rules are searched,
cno: type (destination/called number) rules are searched,
cli: type (caller id) rules are searched.
After a match for caller's/caller's IP is found, no more rules are checked, even if no prefix/number is matched inside the set of rules for these IPs.

On the Windows platform, there is a problem with duplicated config keys in INI files, so GnuGk provides a workaround for this restriction. This example will not work because of the same key (in:192.168.1.1):

[RewriteCLI]
in:192.168.1.1=1001=2001
in:192.168.1.1=any=2000

As a workaround, you can use a string with percent signs (%) at the beginning and at the end before the key. This prefix will be automatically stripped from the key name before loading rules:
[RewriteCLI]
%r1% in:192.168.1.1=1001=2001
%r2% in:192.168.1.1=any=2000

9. RAS Configuration

9.1 หัวข้อ [RasSrv::GWPrefixes]
This section configures how dialed E.164 numbers are routed to a specific gateway.


Format:
gw-alias=prefix[:=priority][,prefix[:=priority],...]

Note that you must specify the alias of the gateway. If a gateway has registered with the specified alias, all numbers beginning with the prefixes are routed to that gateway. Special characters . and ! can be used here to match any digit or to disable the prefix. A priority can be given to each prefix for each gateway (using := syntax), so that if several gateways match the dialed number, the one with the highest prefix priority will be selected to route the call (when the ActivateFailover switch is ON, the call will be routed to all selected gateways in order of the prefix priority). A smaller value corresponds to a higher priority. Default value is 1. If the prefix priority and overlaps the GatewayPriority (see section [EP::...]), the prefix priority will be preferred.

In the following example, the gateway "test-gw" will be responsible for prefixes "02" and "03" with a priority of 3, and for "04" with a priority of 1.


Example:
test-gw=02,03:=3,04:=1

9.2 หัวข้อ [RasSrv::PermanentEndpoints]

In this section you may configure endpoints that don't have RAS support or that you don't want to be expired. Their records will always remain in the registration table of the gatekeeper. However, you can still unregister it via the status port. Special characters . and ! can be used with prefixes here to match any digit and disable the prefix. You may use := syntax to set a prefix priority in the same manner as in [RasSrv::GWPrefixes] section.

Format:
IP[:port]=alias[,alias,...;prefix[:=priority][,prefix[:=priority]]...]

Example:
For gateway,

10.0.1.5=MyGW;009,008:=2,0.7:=3
For terminal,
10.0.1.10:1720=700

9.3 หัวข้อ [RasSrv::RRQFeatures]

AcceptEndpointIdentifier=1
Default: 1

Whether to accept endpointIdentifier specified in a full RRQ.


AcceptGatewayPrefixes=1
Default: 1

A gateway can register its prefixes with the gatekeeper by sending supportedPrefixes in the terminalType field of the RRQ. This option defines whether to accept the specified prefixes of a gateway.


AcceptMCUPrefixes=1
Default: 1

A MCU can register its prefixes with the gatekeeper by sending supportedPrefixes in the terminalType field of the RRQ. This option defines whether to accept the specified prefixes of a MCU.



OverwriteEPOnSameAddress=1
Default: 0

In some networks an endpoint's IP address may change unexpectedly. This may happen when an endpoint is using a PPP connection (e.g. modem or ADSL). This option defines how to handle a registration request (RRQ) from an IP address which does not match what we have stored. The default action is to reject the request. With this option enabled the conflicting request will cause an unregister request (URQ) to be sent for the existing IP address and the entry to be removed, allowing the endpoint to register with the new address.


IRQPollCount=0
Default: 1

When the gatekeeper does not receive a keep-alive RRQ from an endpoint within the TimeToLive time period, it sends an IRQ message to "poll" the endpoint and check if it is alive. After IRQPollCount messages are sent and no reply is received, the endpoint is unregistered. To disable this feature (and unregister endpoints immediately after TimeToLive timeout), set this variable to 0. IRQ poll interval is 60 seconds.


SupportDynamicIP=1
Default: 0

When the IP address of an endpoint changes, the gatekeeper can maintain registration. This will force the EP to fully re-register if its IP address changes.


AccHTTPLink=https://billing.mysite.com?account=%a&password=%p
Default: N/A

You can assign a URL for clients to access to view billing information. If using PacPhone you can also add wildcards for the client to use so the clients H323ID and password can be used to directly access their account information. %a - H323ID %p - password


AliasTypeFilter=terminal;h323id,dialeddigits
Default: N/A

Use this setting where endpoints send multiple H225_AliasAddress and some Aliases are shared across multiple registrations. You can filter out the shared alias types for any given endpoint type. The registrations will keep all alias types listed in the filter setting and remove all others. You must have separate AliasTypeFilter entries for each endpoint type. Valid endpoint types are: gatekeeper, gateway, mcu and terminal. Valid filters are: h323id, dialeddigits, url, transport, email and partynumber. NOTE: If no alias is found that match the filter then all aliases are registered.

9.4 หัวข้อ [RasSrv::ARQFeatures]

ArjReasonRouteCallToGatekeeper=1
Default: 1

If enabled, the gatekeeper rejects an answered ARQ without a pre-existing CallRec found in the CallTable by reason routeCallToGatekeeper in routed mode. The endpoint shall release the call immediately and re-send call Setup to the gatekeeper.


RemoveTrailingChar=#
Default: N/A

Specify the trailing character to be removed in destinationInfo. For example, if your endpoint incorrectly contains a termination character such as `#' in destinationInfo you may remove it with this option.


RoundRobinGateways=0
Default: 1

Enable/disable round-robin gateway selection if more than one gateway matches a dialed number. If disabled, the first available gateway will be selected. Otherwise, subsequent calls will be sent to gateways in round-robin fashion.