Configure WCCP on a 4510 switch

Question

I have to configure an instance of a WCCP on a 4510 switch and I have to admit  have read the examples given by Cisco but dont have understanding of the example config
Router(config)#
ip wccp web-cache group-address 224.1.1.100 password alaska1
I have attached the config in question above and could someone please clarify what the group address  224.1.1.100 is ?
Many Thanks
Mark

Answer 1

Now I have used what you say which is
ip wccp 99 group-list websense_proxy (Proxy server) but it does not give the option to create redirect list and this is the out put of sh ip wccp
Service Identifier: 99
        Number of Service Group Clients:     0
        Number of Service Group Routers:     0
        Total Packets s/w Redirected:        0
          Process:                           0
          CEF:                               0
        Redirect access-list:                -none-
        Total Packets Denied Redirect:       0
        Total Packets Unassigned:            0
        Group access-list:                   websense_proxy
        Total Messages Denied to Group:      0
        Total Authentication failures:       0
        Total Bypassed Packets Received:     0 Service Identifier: 99
        Number of Service Group Clients:     0
        Number of Service Group Routers:     0
        Total Packets s/w Redirected:        0
          Process:                           0
          CEF:                               0
        Redirect access-list:                -none-
        Total Packets Denied Redirect:       0
        Total Packets Unassigned:            0
        Group access-list:                   websense_proxy
        Total Messages Denied to Group:      0
        Total Authentication failures:       0
        Total Bypassed Packets Received:     0