sipt Module

Torrey Searle

Voxbone SA

Table of Contents

1. Admin Guide
1. Overview
2. Dependencies
3. Functions
3.1. sipt_destination(destination, hops, nai[, terminator=1])
3.2. sipt_set_bci_1(charge_indicator, called_status, called_category, e2e_indicator)
3.3. sipt_set_calling(origin, nai, presentation, screening)
3.4. sipt_forwarding(origin, nai)
3.5. sipt_has_isup_body()
4. Exported pseudo-variables
4.1. $sipt(calling_party_number.presentation) / $sipt_presentation
4.2. $sipt(calling_party_number.screening) / $sipt_screening
4.3. $sipt(hop_counter) / $sipt_hop_counter
4.4. $sipt(calling_party_category) / $sipt(cpc) / $sipt_cpc
4.5. $sipt(calling_party_number.nature_of_address) / $sipt.(calling_party_number.nai) / $sipt_calling_party_nai
4.6. $sipt(calling_party_number)
4.7. $sipt(called_party_number.nature_of_address) / $sipt(called_party_number.nai) / $sipt_called_party_nai
4.8. $sipt(called_party_number)
4.9. $sipt(event_info)
4.10. $sipt(backward_call_indicator.charge_indicator)
4.11. $sipt(redirection_info) / $sipt_redirection_info
4.12. $sipt(redirection_number) / $sipt_redirection_number
4.13. $sipt(redirection_number.nai) / $sipt_redirection_number_nai
4.14. $sipt(redirection_information.reason)
4.15. $sipt(redirection_information.original_reason)
4.16. $sipt(redirecting_number.nai)
4.17. $sipt(redirecting_number)
4.18. $sipt(original_called_number.nai)
4.19. $sipt(original_called_number)
4.20. $sipt(generic_number.nai)
4.21. $sipt(generic_number)

List of Tables

1.1. Address Presentation Restricted Indicator Values
1.2. Screening Indicator Values
1.3. Calling Nature of Address Values
1.4. Called Nature of Address Values
1.5. Event Info Values
1.6. Charge Indicator Values
1.7. Redirecting reason Values
1.8. Redirecting number NAI Values

List of Examples

1.1. sipt_destination(destination, hops, nai) usage
1.2. sipt_destination(destination, hops, nai) usage
1.3. sipt_set_calling(origin, nai, presentation, screening) usage
1.4. sipt_set_calling(origin, nai) usage
1.5. sipt_has_isup_body() usage
1.6. sipt_presentation pseudo-variable usage
1.7. sipt_screening pseudo-variable usage
1.8. sipt_hop_counter pseudo-variable usage
1.9. sipt_cpc pseudo-variable usage
1.10. sipt_calling_party_nai pseudo-variable usage
1.11. sipt_called_party_nai pseudo-variable usage
1.12. sipt_redirection_number usage

Chapter 1. Admin Guide

1. Overview

Module for updating ISUP encapsulated in SIP (SIP-T/SIP-I)

The sipt module can be used to update various ss7 headers contained inside a message.

2. Dependencies

The module depends on the following modules (in the other words the listed modules must be loaded before this module):

  • none

3. Functions

3.1. sipt_destination(destination, hops, nai[, terminator=1])

updates the IAM in the body if it exists, setting the called party number to destination with the nature address specified in nai and decrementing the hop counter value if present. If the hop counter header is missing it will be added with the value of hops. If terminator is set to 1, then F will be appended to digit string to indicate the number is complete (default).

Example 1.1. sipt_destination(destination, hops, nai) usage

...
# update the destination number to our current request uri, 
# setting nature of address to international
$rU = "19495551234";
sipt_destination($rU, 31, 4);
...

3.2. sipt_set_bci_1(charge_indicator, called_status, called_category, e2e_indicator)

updates the first byte of the backward call indicator in the ACM or COT in the body if setting the Charge Indicator to charge_indicator, the Called party's status indicator in called_status, the Called party's category indicator in called_category and the End to End Method Indicator with the value of the value of e2e_indicator.

Example 1.2. sipt_destination(destination, hops, nai) usage

...
# set bci for charging, subscriber free, ordinary, no e2e available
sipt_set_bci_1("2", "1", "1", "0");
...

3.3. sipt_set_calling(origin, nai, presentation, screening)

updates the IAM in the body if it exists, setting (or adding) the calling party number to origin with the nature address specified in nai and setting the presentation and screening values to presentation and screening.

Example 1.3. sipt_set_calling(origin, nai, presentation, screening) usage

...
# update the calling party to the value in the from header
sipt_set_calling($fU, 4, 0, 3);
...

3.4. sipt_forwarding(origin, nai)

updates the IAM in the body if it exists, setting (or adding) the forwarding number to origin with the nature address specified in nai.

Example 1.4. sipt_set_calling(origin, nai) usage

...
# update the forwarding number to the value in the from header
sipt_forwarfing($avp(s:forwarding_number), 3);
...

3.5. sipt_has_isup_body()

The function returns true if the SIP message has a ISUP body attached.

Example 1.5. sipt_has_isup_body() usage

...
if(sipt_has_isup_body())
{
    # do interesting stuff here
}
...

4. Exported pseudo-variables

4.1. $sipt(calling_party_number.presentation) / $sipt_presentation

Returns the value of the Address presentation restricted indicator contained in the Calling Party Number header of the IAM message if it exists. Returns -1 if there isn't a Calling Party Number header.

Table 1.1. Address Presentation Restricted Indicator Values

0 presentation allowed
1 presentation restricted
2 address not avail (national use)
3 spare

Example 1.6. sipt_presentation pseudo-variable usage

...
# add privacy header if restriction is requested 
if($sipt(calling_party_number.presentation) == 1)
{
	append_hf("Privacy: id\r\n");
	$fn = "Anonymous";
}

...

4.2. $sipt(calling_party_number.screening) / $sipt_screening

Returns the value of the Screening Indicator contained in the Calling Party Number header of the IAM message if it exists. Returns -1 if there isn't a Calling Party Number header.

Table 1.2. Screening Indicator Values

0 Reserved (user provided, not verified)
1 User Provided, Verified and Passed
2 Reserved (user provided, verified and failed)
3 Network provided

Example 1.7. sipt_screening pseudo-variable usage

...

# remove P-Asserted-Identity header if the screening isn't verified 
# or network provided
$avp(s:screening) = $sipt(calling_party_number.screening);
if($avp(s:screening) != 1 && $avp(s:screening) != 3)
{
	remove_hf("P-Asserted-Id");
}

...

4.3. $sipt(hop_counter) / $sipt_hop_counter

Returns the value of the Hop Counter for the IAM message if it exists. Returns -1 if there isn't a hop counter.

Example 1.8. sipt_hop_counter pseudo-variable usage

...
# get the hop counter and update the Max-Forwards header if it exists
$avp(s:hop) = $sipt(hop_counter);
if($avp(s:hop) > 0)
{
	remove_hf("Max-Forwards");
	append_hf("Max-Forwards: $avp(s:hop)\r\n");
}

...

4.4. $sipt(calling_party_category) / $sipt(cpc) / $sipt_cpc

Returns the value of the Calling Party Category for the IAM message. Returns -1 if there is a parsing error.

Example 1.9. sipt_cpc pseudo-variable usage

...
# get the Cpc code and set put it in a custom sip header
append_hf("X-CPC: $sipt(cpc)\r\n");

...

4.5. $sipt(calling_party_number.nature_of_address) / $sipt.(calling_party_number.nai) / $sipt_calling_party_nai

Returns the value of the Nature of Address Indicator of the Calling Party for the IAM message. Returns -1 if there is a parsing error or if the Calling Party Number is not present.

Table 1.3. Calling Nature of Address Values

0 Spare
1 Subscriber Number (national use)
2 Unknown (national use)
3 National (significant) number (national use)
4 International use

Example 1.10. sipt_calling_party_nai pseudo-variable usage

...
# get the Calling Nai and add country code if national
if($sipt(calling_party_number.nai) == 3)
{
	$fU = "32" + "$fU";
}

...

4.6. $sipt(calling_party_number)

Returns the value (Address signal) of the Calling Party for the IAM message. Returns -1 if there is a parsing error or if the Calling Party Number is not present.

4.7. $sipt(called_party_number.nature_of_address) / $sipt(called_party_number.nai) / $sipt_called_party_nai

Returns the value of the Nature of Address Indicator of the Called Party for the IAM message. Returns -1 if there is a parsing error.

Table 1.4. Called Nature of Address Values

0 Spare
1 Subscriber Number (national use)
2 Unknown (national use)
3 National (significant) number
4 International use
5 Network-specific number (national use)

Example 1.11. sipt_called_party_nai pseudo-variable usage

...
# get the Called Nai and add country code if national
if($sipt(called_party_number.nai) == 3)
{
	$rU = "32" + "$rU";
}

...

4.8. $sipt(called_party_number)

Returns the value (Address signal) of the Called Party for the IAM message. Returns -1 if there is a parsing error or if the Called Party Number is not present.

4.9. $sipt(event_info)

Returns the value of the Event Info header of the CPG message. Returns -1 if there is a parsing error.

Table 1.5. Event Info Values

0 Spare
1 ALERTING
2 PROGRESS
3 In-band information or an appropriate pattern is now available
4 Call forward on busy
5 Call forward on no reply
6 Call forward unconditional

4.10. $sipt(backward_call_indicator.charge_indicator)

Returns the value of the charge indication of the backward call indicator header in the ACM or COT message. Returns -1 if there is a parsing error.

Table 1.6. Charge Indicator Values

0 no indication
1 no charge
2 charge
3 spare

4.11. $sipt(redirection_info) / $sipt_redirection_info

Returns call diversion information header from ISUP Returns "Redirecting reason" or -1 if no call diversion information found.

Table 1.7. Redirecting reason Values

0 Unknown
1 User busy
2 PROGRESS
3 no reply
4 deflection during alerting
5 deflection immediate response
6 mobile subscriber not reachable

4.12. $sipt(redirection_number) / $sipt_redirection_number

Returns number to which redirection will trigered Returns -1 if there is a parsing error.

Example 1.12. sipt_redirection_number usage

...
# get the redirection number
$avp(s:redir_num) = $sipt(redirection_number);

...

4.13. $sipt(redirection_number.nai) / $sipt_redirection_number_nai

Returns NAI for redirection number from ISUP Returns NAI for redirection number or -1 if no info found.

Table 1.8. Redirecting number NAI Values

0 Spare
1 Subscriber Number (national use)
2 Unknown (national use)
3 National (significant) number (national use)
4 International use

4.14. $sipt(redirection_information.reason)

Returns redirection reason from Redirection information from ISUP or -1 if no Redirection information found.

4.15. $sipt(redirection_information.original_reason)

Returns original redirection reason from Redirection information from ISUP or -1 if no Redirection information found.

4.16. $sipt(redirecting_number.nai)

Returns NAI for redirecting number from ISUP or -1 if no redirecting number found.

4.17. $sipt(redirecting_number)

Returns redirecting number from ISUP or -1 if no redirecting number found.

4.18. $sipt(original_called_number.nai)

Returns NAI for original called number from ISUP or -1 if no original called number found.

4.19. $sipt(original_called_number)

Returns original called number from ISUP or -1 if no original called number found.

4.20. $sipt(generic_number.nai)

Returns NAI for generic number from ISUP or -1 if no generic number found.

4.21. $sipt(generic_number)

Returns generic number from ISUP or -1 if no generic number found.