IOS IPS config Steps

• Enabling IOS IPS on a router is fairly simple
• Globally load the IPS Signature Package
• Then create an IPS Rule
• Then apply that rule to an interface either inbound or outbound
• To decrypt the signature files we need an RSA Key based on the Cisco Public key
• Configuration steps
• "retire"(disable) all signature categories & then "unretire" (enable) the basic IOS IPS category.
• created a directory in flash to store the IPS configuration
• Create an IOS IPS rule.
• Specify the location of the signature configuration information.
• Apply the 

Cisco Intrusion Prevent System (IPS)

• Cisco IPS is a feature that must be enable on Cisco routers.
• It provides Deep Packet Inspection (DPI) of traffic transiting the router.
• This is especially useful in branch offices
• to catch worms, viruses, and other exploits before they leave the local site.
• Routers with the security image come with a package of signature files loaded in their flash.
• Signature updates are posted on the Cisco website.
• These signature updates are downloaded to TFTP server & then to server.
• When IOS IPS is configured, the router acts as an inline IPS,
• & compare each packet that flows through it to known signature.
• Router actions upon finding a signature match include
• Dropping the packet
• Resetting the connection
• Sending an alarm log message
• Blocking traffic from the packet source for a configurable amount of time
• Blocking traffic on the connection for a configurable amount of time
• IOS IPS can be configurable through the command line,
• or, using the Security Device Manger(SDM)
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ZFW Configuration

• Create the desired zones on the router
• Decide how traffic should travel between the zones
• and then create zone-pairs on the router
• Create Class maps
• to identify the inter-zone traffic
• that must be inspected by the firewall
• Create Policy maps
• to assign policies to traffic
• ans associate class maps with them.
• Policy Maps were assigned to the appropriate zone-pair.
• Assign interfaces to zones.
• an interface may be assigned to only one security zone
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ZFW Inspection & Controlling of Protocols

• HTTP & HTTPS
• SMTP, Extened SMTP(ESMTP), POP3, & IMAP
• Peer-to-peer applications, with the ability to use heuristics to track port hopping
• Instant messaging applications(AOl, Yahoo!, & MSM as of this writing)
• Remote Procedure Calls (RPC)
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Cisco IOS Zone-Based Firewall

• Classic IOS, inspection policies were applied to all traffic on that interface,
• we can't apply to different policies to different groups of users.
• Zone-based firewall (ZFW), available in IOS release 12.4(6)T or later.
• This concept(ZFW) is similar to that used by appliance firewalls.
• Router interfaces are placed into security zones.
• Traffic between zones were blocked by default.
• Some times traffic blocked between interfaces that have been assigned to a security zone & those that have not.
• We must explicitly apply a policy to allow traffic between zones.
• Zone policies are configured using the Class-based Policy Language(CPL), 
• which is similar to Modular QoS Command Line Interface (MQC) 
• in its use of class maps and policy maps.
• Class maps let you configure highly granular policies if needed.
• A new class & policy map type, the inspect type, is introduced for zone-based firewalls.
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