Ruleset Replacement Expressions

Ruleset replacement expressions are used when the value of a parameter, a command or an action is not known in advance, i.e. the value depends on the result of the SIP message processing.

A Ruleset replacement expression is a string that represents a SIP processing status. Replacement expressions always start with the dollar (“$”) sign followed by an identifier. When the Ruleset uses a replacement expression, the replacement expression is replaced by the value of the SIP processing status representing the replacement expression.

For example,
  • $aU uses the User part of the P-Asserted-Identity header
  • $th uses the Host part of the To header
  • sip:$aU@$th, used as the parameter of the Set R-URI action, uses the P-Asserted-Identity and To headers of the incoming request and puts them into the Request URI of the outgoing request.
Note: Special characters should be backslash-escaped, for example, as follows: \ → \\ or $ → \$
Note: It is important to know that if a mediation action (Section SIP Mediation) changes the content of a SIP message, the replacement expression will refer to the value after modification. E.g., if you apply the rule action “SetFrom(”, $fu will return!


Ruleset Replacement Expression Exhaustive List

Macro Replacements Description
$r $r. request-URI; note that the expression refers to current request URI which may be changed during the course of request processing
$ru user@host[:port] part of request URI
$rU R-URI User
$rd R-URI Domain (host:port)
$rh R-URI Host
$rp R-URI Port
$rP R-URI Parameters
$f $f. From header
$fu user@host[:port] part of From URI
$fU From User
$fd From Domain (host:port)
$fh From Host
$fp From Port
$fn From Display name
$fP From Parameters
$ft From Tag
$fH From header Headers
$t $t. To header
$tu user@host[:port] part of To URI
$tU To User
$td To Domain (host:port)
$th To Host
$tp To Port
$tn To Display name
$tP To Parameters
$tt To Tag
$tH To header Headers
$a $a. P-Asserted-Identity header
$au user@host[:port] part of P-Asserted-Identity URI
$aU P-Asserted-Identity User
$ad P-Asserted-Identity Domain (host:port)
$ah P-Asserted-Identity Host
$ap P-Asserted-Identity Port
$aP P-Asserted-Identity Parameters
$at P-Asserted-Identity Tag
$aH P-Asserted-Identity Headers
$p $p. P-Preferred-Identity header
$pu user@host[:port] part of P-Preferred-Identity URI
$pU P-Preferred-Identity User
$pd P-Preferred-Identity Domain (host:port)
$ph P-Preferred-Identity Host
$pp P-Preferred-Identity Port
$pP P-Preferred-Identity Parameters
$pt P-Preferred-Identity Tag
$pH P-Preferred-Identity Headers
$c $ci Call-ID
$s $si Source (remote) IP address
$sp Source (remote) port number
$d $di expected destination host
$dp expected destination port
$R $Ri Destination (local/received) IP address
$Rp Destination (local/received) port number
$Rf local/received interface id (0=default)
$Rn local/received interface name (SBC interface name)
$RI local/received interface public IP
$H $H(headername) value of header with the name headername (Note: not all headers are available here)
$HU(headername) header headername (as URI) User
$Hd(headername) header headername (as URI) domain (host:port)
$Hu(headername) header headername (as URI) URI
$Hd(headername) header headername (as URI) domain (host:port)
$Hh(headername) header headername (as URI) host
$Hp(headername) header headername (as URI) port
$Hn(headername) header headername (as URI) display name
$Hp(headername) header headername (as URI) parameters
$HH(headername) header headername (as URI) headers
$m $m request method
$V $V(gui.varname) value of Call Variable varname
$B $B(cnum.rnum) value of backreference with rnum number from the condition with cnum number
$U $Ua register cache: originating AoR
$UA register cache: originating alias
$_ $_u(value) value to uppercase
$_l(value) value to lowercase
$_s(value) length of value (size)
$_5(value) MD5 of value
$_r(value) random number 0..value, e.g. $_r(5) gives 0, 1, 2, 3 or 4
$# $#(value) value URL-encoded


DGW Documentation

Mediatrix units are supplied with an exhaustive set of documentation.

Mediatrix user documentation is available on the Media5 Documentation Portal at

Several types of documents were created to clearly present the information you are looking for. Our documentation includes:

  • Release notes: Generated at each GA release, this document includes the known and solved issues of the software. It also outlines the changes and the new features the release includes.
  • Configuration notes: These documents are created to facilitate the configuration of a specific use case. They address a configuration aspect we consider that most users will need to perform. However, in some cases, a configuration note is created after receiving a question from a customer. They provide standard step-by-step procedures detailing the values of the parameters to use. They provide a means of validation and present some conceptual information. The configuration notes are specifically created to guide the user through an aspect of the configuration.
  • Technical bulletins: These documents are created to facilitate the configuration of a specific technical action, such as performing a firmware upgrade.
  • Hardware installation guide: They provide the detailed procedure on how to safely and adequately install the unit. It provides information on card installation, cable connections, and how to access for the first time the Management interface.
  • User guide: The user guide explains how to customise to your needs the configuration of the unit. Although this document is task oriented, it provides conceptual information to help the user understand the purpose and impact of each task. The User Guide will provide information such as where and how TR-069 can be configured in the Management Interface, how to set firewalls, or how to use the CLI to configure parameters that are not available in the Management Interface.
  • Reference guide: This exhaustive document has been created for advanced users. It includes a description of all the parameters used by all the services of the Mediatrix units. You will find, for example, scripts to configure a specific parameter, notification messages sent by a service, or an action description used to create Rulesets. This document includes reference information such as a dictionary, and it does not include any step-by-step procedures.


Copyright Notice

Copyright © 2020 Media5 Corporation.

This document contains information that is proprietary to Media5 Corporation.

Media5 Corporation reserves all rights to this document as well as to the Intellectual Property of the document and the technology and know-how that it includes and represents.

This publication cannot be reproduced, neither in whole nor in part, in any form whatsoever, without written prior approval by Media5 Corporation.

Media5 Corporation reserves the right to revise this publication and make changes at any time and without the obligation to notify any person and/or entity of such revisions and/or changes.