You want to create a custom IDP signature for a new HTTP attack on your SRX device. You have the exact
string that identifies the attack. Which two additional elements do you need to define your custom signature?
(Choose two.)

A.
service context

B.
protocol number

C.
direction

D.
source IP address of the attacker

Explanation:
http://rtoodtoo.net/2011/09/22/how-to-write-srx-idp-custom-attacksignature/