Cisco Wide Area Application Engine 612 Manual de usuario descargar pdf (Pagina 13)

Interception Techniques and Protocols 87

of the WCCPv2 protocol, you are encouraged to read the WCCPv2 protocol draft. The full

WCCPv2 IETF draft is available online at http://www.wrec.org/Drafts/draft-wilson-wrec-

wccp-v2-00.txt.

WCCP Overview

WCCP is a transparent interception protocol ﬁrst developed by Cisco Systems, Inc. in

1997. WCCP is a control plane protocol that runs between devices running Cisco IOS and

WCCP “clients” such as WAAS. The protocol enables the network infrastructure to

selectively intercept trafﬁc based on IP protocol and port numbers, and redirect that trafﬁc

to a WCCP client. WCCP is considered transparent, because it allows for local interception

and redirection of trafﬁc without any conﬁguration changes to the clients or servers. WCCP

has built-in load-balancing, scalability, fault-tolerance, and service assurance (fail open)

mechanisms. Figure 4-4 shows the basic functions of WCCP.

Figure 4-4 Basic WCCP Functionality

The current version, WCCPv2, is used by Cisco WAAS to transparently intercept and

redirect all TCP trafﬁc, regardless of port. The following section describes the basic

WCCPv2 concepts and how they are speciﬁcally used by Cisco WAAS.

Service Groups

The routers and WAEs participating in the same service constitute a service group. A ser-

vice group deﬁnes a set of characteristics about what types of trafﬁc should be intercepted,

as well as how the intercepted trafﬁc should be handled. There are two types of service

groups:

• Well-known services

• Dynamic services

WAN

WAE

WCCP transparently intercepts

traffic and redirects it to a WAE.

1 2 ... 8 9 10 11 12 13 14 15 16 17 18 ... 40 41

Sin comentarios

Cisco Wide Area Application Engine 612 Manual de usuario Pagina 13