Cisco 5505 - ASA Firewall Edition Bundle, Cli Configuration Manual

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Cisco ASA Series CLI Configuration Guide
Chapter 1 Configuring Inspection for Voice and Video Protocols
RTSP Inspection
If using UDP mode on the RealPlayer, select the Use TCP to Connect to Server and Attempt to use
UDP for static content check boxes, and for live content not available via Multicast. On the ASA, add
an inspect rtsp port command.
Restrictions and Limitations
The following restrictions apply to the RSTP inspection.
•
The ASA does not support multicast RTSP or RTSP messages over UDP.
•
The ASA does not have the ability to recognize HTTP cloaking where RTSP messages are hidden
in the HTTP messages.
•
With Cisco IP/TV, the number of translates the ASA performs on the SDP part of the message is
proportional to the number of program listings in the Content Manager (each program listing can
have at least six embedded IP addresses).
•
You can configure NAT for Apple QuickTime 4 or RealPlayer. Cisco IP/TV only works with NAT
if the Viewer and Content Manager are on the outside network and the server is on the inside
network.
Configuring an RTSP Inspection Policy Map for Additional Inspection
Control
To specify actions when a message violates a parameter, create an RTSP inspection policy map. You can
then apply the inspection policy map when you enable RTSP inspection.
To create an RTSP inspection policy map, perform the following steps:
Step 1
(Optional) Add one or more regular expressions for use in traffic matching commands according to the
“Configuring Regular Expressions” section on page 1-14 . See the types of text you can match in the
match commands described in Step 3 .
Step 2
(Optional) Create one or more regular expression class maps to group regular expressions according to
the
“Creating a Regular Expression Class Map” section on page 1-17 .
Step 3
(Optional) Create an RTSP inspection class map by performing the following steps.
A class map groups multiple traffic matches. Traffic must match all of the match commands to match
the class map. You can alternatively identify match commands directly in the policy map. The difference
between creating a class map and defining the traffic match directly in the inspection policy map is that
the class map lets you create more complex match criteria, and you can reuse class maps.
To specify traffic that should not match the class map, use the match not command. For example, if the
match not command specifies the string “example.com,” then any traffic that includes “example.com”
does not match the class map.
For the traffic that you identify in this class map, you can specify actions such as drop-connection and/or
log the connection in the inspection policy map.
If you want to perform different actions for each match command, you should identify the traffic directly
in the policy map.
a.
Create the class map by entering the following command:
hostname(config)# class-map type inspect rtsp [ match-all | match-any ] class_map_name
hostname(config-cmap)#