Filter
Top Products
Call Server Configuration
Polycom, Inc. 254
Preliminary/Postliminary Scripting
A preliminary is an executable script, written in the Javascript language, that defines processing actions
(filtering or transformation) to be applied to a dial string before the dial rule’s action is performed.
A postliminary is an executable script, written in the Javascript language, that defines dial string
transformations to be applied before querying an external device (gatekeeper, SIP peer, SBC, or MCU).
Transformation scripts output some modification of the DIAL_STRING variable (which is initially set to the
dial string being evaluated).
Filtering scripts may pass the dial string on to the dial rule’s action (if the filter criteria aren’t met) or return
one of the following:
● NEXT_RULE: Skips the rule being processed and passes the dial string to the next rule.
● BLOCK: Rejects the call.
See Sample Preliminary and Postliminary Scripts for some examples.
Predefined Preliminary/Postliminary Scripting Variables
The following table describes the predefined variables you can use in a preliminary or postliminary script.
The script can evaluate a variable or change its value (the change isn’t preserved after the script completes).
Variable Initial value
CALLER_E164 For H.323 calls only, an array variable initially set to the set of E.164
addresses of the caller. The length of the array is 0 if the caller doesn’t have
an E.164 address.
CALLER_H323ID Array variable initially set to the set of H323ID addresses of the caller. The
length of the array is 0 if the caller doesn’t have an H323ID address.
CALLER_IS_IPV6 “TRUE” if the caller is an IPv6 endpoint. Blank otherwise.
CALLER_SIP_URI Array variable initially set to the set of SIP URI addresses of the caller. The
length of the array is 0 if the caller doesn’t have a SIP URI address.
CALLER_SITE_AREA
_CODE
Area code of the caller’s site. Blank if the site doesn’t have an area code.
CALLER_SITE_COUNTRY_COD
E
Country code of the caller’s site. Blank if the site doesn’t have a country
code.
CALLER_SITE_DIGITS The number of subscriber number digits in the caller’s site (that is, the length
of a phone number at the site, excluding area code). Blank if the site doesn’t
have a number of digits.
CALLER_SITE_NAME The name of the caller’s site.
CALLER_SITE_SITE
_CODE
The site code of the caller’s site.
CALLER_TEL_URI Array variable initially set to the set of Tel URI addresses of the caller. The
length of the array is 0 if the caller doesn’t have a Tel URI address.