Cisco ASR 5000 Series Administration Manual page 22

▀ Basic Features and Functionality
Step 2 When a field or state from the output of the deep-packet inspection matches a field or state defined in a charging
ruledef, the ruledef action is applied to the packet. Actions can include redirection, charge value, or billing record
emission. It is also possible that a match does not occur and no action will be applied to the packet at all.
Regular Expression Support for Rule Matching
This section describes ECS support for regular expression (regex) rule matching.
In this release, ECS supports regex rule matching only for the following string-based rules:
 http host
 http referer
 http uri
 http url
 rtsp uri
 wsp url
 www url
The following table lists the special characters that you can use in regex rule expressions.
Table 1. Special Characters Supported in Regex Rule Expressions
Regex Character Description
* Zero or more characters
+ Zero or more repeated instances of the token preceding the +
? Match zero or one character
For example, if you want to match the string "xyz<any one character>pqr", you must configure it as:
http host regex "xyz\077pqr"
In another example, if you want to exactly match the string "url?resource=abc", you must configure it as:
http uri regex "url\\\077resource=abc"
Where, the first "\" (backslash) is for the escaping of "?", and then "\077" for specifying "?" to the CLI.
\character Escaped character
\? Match the question mark (\<ctrl-v>?) character
\+ Match the plus character
\* Match the asterisk character
\a Match the alert (ASCII 7) character
\b Match the backspace (ASCII 8) character
\f Match the form-feed (ASCII 12) character
\n Match the new line (ASCII 10) character
▄ Cisco ASR 5x00 Enhanced Charging Services Administration Guide
22
Important:
The CLI does not support configuring "?" directly, you must instead use
"\077".
Enhanced Charging Service Overview