27. The security appliance of claim 25 wherein the processor is further configured to match the possible matching back-reference with at least one other possible matching back-reference, the possible matching back-reference and the at least one other possible matching back-reference associated with a same capture group.
27. The security appliance of claim 25 wherein the processor is further configured to match the possible matching back-reference with at least one other possible matching back-reference, the possible matching back-reference and the at least one other possible matching back-reference associated with a same capture group. 28. The security appliance of claim 27 wherein the processor is further configured to determine a non-matching back-reference of the given regular expression pattern in an event the possible matching back-reference does not match with the at least one other possible matching back-reference.