SIP-I Module

The following modules must be loaded before this module:

The following libraries or applications must be installed before running OpenSIPS with this module loaded:

The character to be used as separator in the subname of the $isup_param and $isup_param_str pseudovariables between the ISUP parameter name and subfield name.

Default value is "|".

...
modparam("sip_i", "param_subfield_separator", ":")
...

The string to be used for the Content-Type header field of the ISUP MIME body when creating a new ISUP part.

Default value is "application/ISUP;version=itu-t92+".

...
modparam("sip_i", "isup_mime_str", "application/ISUP;base=itu-t92+;version=itu-t")
...

The default set of headers (fully defined, including the header termination) to be pushed into the ISUP part together with the Content-Type header.

Default value is "Content-Disposition:signal;handling=optional\r\n".

...
modparam("sip_i", "default_part_headers", "Content-Disposition:signal;handling=required\r\n")
...

Country Code that the first part of the number from P-Asserted-Identity is tested against when trying to map the Calling Party Number ISUP parameter from SIP by default. If there is a match, the value assigned to the Nature of Address Indicator subfield is 3(national), otherwise it is 4(international).

Default value is "+1".

...
modparam("sip_i", "country_code", "+4")
...

Adds a new ISUP part to the SIP message body.

With the exception of some ISUP message types(IAM, REL, ACM, CPG, ANM, CON), the newly added part contains a blank ISUP message(i.e. all mandatory parameters zeroed and no optional ones) and all the required parameters should be set through $isup_param. For the previously mentioned message types, the mandatory parameters and some optional ones are automaticaly set to default values according to basic SIP-ISUP interworking rules from ITU-T Rec. Q.1912.5. This only provides a general and simplified mapping from SIP headers and message type (request method, reply code etc.) to ISUP parameters and you should not base your SIP-ISUP interworking only on this.

Meaning of the parameters is as follows:

If isup_msg_type is not explicitly provided, it is automatically deduced from the SIP message as follows:

The abbreviations that can be given as isup_msg_type for each ISUP message type are the following:

This function can be used from REQUEST_ROUTE,FAILURE_ROUTE,ONREPLY_ROUTE,LOCAL_ROUTE.

...
if ($rs == "183") {
	# Encapsulate a CPG
	add_isup_part("Call progress");
	# set desired parameters
	...
}
...
	

The ISUP parameter named param_name of a received or newly added ISUP message can be accessed through this read-write variable. For optional parameters, writing to a param_name that does not exist in this ISUP message will insert it. Assigning null to this variable will remove the optional parameter from the message or zeroize the parameter in case of a mandatory one.

The format of the subname for $isup_param is the following:

The ISUP parameter can be addressed in different ways:

Addressing at entire parameter level as a hex string and at byte level are supported for all the ISUP parameters defined in the ITU-T Rec. Q.763. Addressing at subfield level is supported only for some ISUP parameters and not all of the subfields of a parameter defined in the ITU Recommandation are supported.

String aliases are not available for all parameters or parameter subfields. Also, not all the possible values of a parameter or parameter subfield have a string alias defined.

For more information on supported subfields and aliases check Section 1.7, “ISUP parameter subfields and string aliases”.

...
	$isup_param(Called Party Number | Nature of address indicator) = 3;
	...
	# use a string alias
	$isup_param(Called Party Number | Numbering plan indicator) = "ISDN";
	...
	$isup_param(Called Party Number | Address signal) = "99991234";
	$isup_param(Nature of connection indicators) = "0x01"
	$isup_param(Calling party's category) = 10;
	...
	# use a string alias
	$isup_param(Transmission Medium Requirement) = "speech";
	...
	# access at byte level
	$(isup_param(Forward Call Indicators)[0]) = 96;
	$(isup_param(Forward Call Indicators)[1]) = 1;
...
	

The ISUP parameter named param_name of a received or newly added ISUP message can also be accessed through this read-only variable. This variable is similar in usage with $isup_param except it will return the string alias for the value when possible.

The format of the subname for $isup_param_str is the following:

...
	# may print: "NOA is: national"  
	xlog("NOA is: $isup_param_str(Called Party Number|Nature of address indicator)");
	# may print: "CpN is: 99991234"
	xlog("CpN is: $isup_param_str(Called Party Number|Address signal)");
	# may print: "nature of conn: 0x01"
	xlog("nature of conn: $isup_param_str(Nature of connection indicators)");
	# may print: "Cg cat is: ordinary"
	xlog("$isup_param_str(Calling party's category)");
...
	

Read-only variable, returns the ISUP message type as string.

...
	# may print: "ISUP msg is: IAM"
	xlog("ISUP msg is: $isup_msg_type");
...
	

The result of this transformation is similar to a read access of the $isup_param pseudovariable with the exception that byte level access is not provided.

The parameters for the transformation are:

...
	# for this example, we take the ISUP body from the received SIP-I message
	$var(isup_body) = $(rb[1]);

	# may print: "NOA is: 3"  
	xlog("NOA is: $(var(isup_body){isup.param, Called Party Number, Nature of address indicator})\n");

	# may print: "CpN is: 99991234"  
	xlog("CpN is: $(var(isup_body){isup.param, Called Party Number, Address signal})\n");

	# may print: "Cg cat is: 10"
	xlog("Cg cat is: $(var(isup_body){isup.param, Calling party's category})\n");

	# may print: "nature of conn: 0x01"
	xlog("nature of conn: $(var(isup_body){isup.param, Nature of connection indicators})\n");
...
		

The result of this transformation is similar to a read access of the $isup_param_str pseudovariable with the exception that byte level access is not provided.

The parameters for the transformation are:

...
	# for this example, we take the ISUP body from the received SIP-I message
	$var(isup_body) = $(rb[1]);

	# may print: "NOA is: national"  
	xlog("NOA is: $(var(isup_body){isup.param.str, Called Party Number, Nature of address indicator})\n");

	# may print: "CpN is: 99991234"  
	xlog("CpN is: $(var(isup_body){isup.param.str, Called Party Number, Address signal})\n");

	# may print: "Cg cat is: ordinary"
	xlog("Cg cat is: $(var(isup_body){isup.param.str, Calling party's category})\n");

	# may print: "nature of conn: 0x01"
	xlog("nature of conn: $(var(isup_body){isup.param.str, Nature of connection indicators})\n");
...