Cisco 7604 Configuration Guide - Page 718

Glossary replay-detection RFC RIP RLLA route, routing routed firewall mode RP RPC RSA RSH RTCP RTP RTSP A security service where the receiver can reject old or duplicate packets to defeat replay attacks. Replay attacks rely on the attacker sending out older or duplicate packets to the receiver and the receiver thinking that the bogus traffic is legitimate. Replay-detection is done by using sequence numbers combined with authentication, and is a standard feature of IPSec. Request for Comments. RFC documents define protocols and standards for communications over the Internet. RFCs are developed and published by IETF. Routing Information Protocol. Interior gateway protocol (IGP) supplied with UNIX BSD systems. The most common IGP in the Internet. RIP uses hop count as a routing metric. Reserved Link Local Address. Multicast addresses range from 224.0.0.0 to 239.255.255.255, however only the range 224.0.1.0 to 239.255.255.255 is available to us. The first part of the multicast address range, 224.0.0.0 to 224.0.0.255, is reserved and referred to as the RLLA. These addresses are unavailable. We can exclude the RLLA range by specifying: 224.0.1.0 to 239.255.255.255. 224.0.0.0 to 239.255.255.255 excluding 224.0.0.0 to 224.0.0.255. This is the same as specifying: 224.0.1.0 to 239.255.255.255. The path through a network. In routed firewall mode, the FWSM is counted as a router hop in the network. It performs NAT between connected networks and can use OSPF or RIP. See also transparent firewall mode. Rendezvous Point. An RP acts as the meeting place for sources and receivers of multicast data in a PIM multicast environment. Remote Procedure Call. RPCs are procedure calls that are built or specified by clients and executed on servers, with the results returned over the network to the clients. A public key cryptographic algorithm (named after its inventors, Rivest, Shamir, and Adelman) with a variable key length. The main weakness of RSA is that it is significantly slow to compute compared to popular secret-key algorithms, such as DES. The Cisco implementation of IKE uses a Diffie-Hellman exchange to get the secret keys. This exchange can be authenticated with RSA (or preshared keys). With the Diffie-Hellman exchange, the DES key never crosses the network (not even in encrypted form), which is not the case with the RSA encrypt and sign technique. RSA is not public domain, and must be licensed from RSA Data Security. Remote Shell. A protocol that allows a user to execute commands on a remote system without having to log in to the system. For example, RSH can be used to remotely examine the status of a number of access servers without connecting to each communication server, executing the command, and then disconnecting from the communication server. RTP Control Protocol. Protocol that monitors the QoS of an IPv6 RTP connection and conveys information about the on-going session. See also RTP. Real-Time Transport Protocol. Commonly used with IP networks. RTP is designed to provide end-to-end network transport functions for applications transmitting real-time data, such as audio, video, or simulation data, over multicast or unicast network services. RTP provides such services as payload type identification, sequence numbering, timestamping, and delivery monitoring to real-time applications. Real Time Streaming Protocol. Enables the controlled delivery of real-time data, such as audio and video. RTSP is designed to work with established protocols, such as RTP and HTTP. GL-16 Catalyst 6500 Series Switch and Cisco 7600 Series Router Firewall Services Module Configuration Guide using ASDM OL-20748-01