In the example above, PC-A wants to communicate with PC-B. They are in different VLANs so the traffic will be routed via the RSM (default gateway for the PCs). The first packet will be sent by PC-A and routed by the RSM towards PC-B; a shortcut, PC-A --> PC-B, will be created and all subsequent packets will be Layer 3 switched by the MLS-SE (Supervisor=NFFC).
　　PC-A#ping 12.12.12.12
　　!-- pinging PC-B
　　
　　Type escape sequence to abort.
　　Sending 5, 100-byte ICMP Echos to 12.12.12.12, timeout is 2 seconds:
　　!!!!!
　　SUCcess rate is 100 percent (5/5), round-trip min/avg/max = 1/3/4 ms
　　
　　On the switch:
　　
　　
　　switch-MLS-SE (enable) show mls entry
　　Destination IP Source IP Prot DstPrt SrcPrt Destination Mac Vlan Port
　　--------------- --------------- ---- ------ ------ ----------------- ---- -----
　　MLS-RP 11.11.11.1:
　　11.11.11.11 12.12.12.12 ICMP - - 00-d0-58-43-9f-60 11 6/11
　　!-- As in the note above we have two shortcuts A->B and B->A
　　12.12.12.12 11.11.11.11 ICMP - - 00-00-0c-07-ac-01 12 6/12
　　switch-MLS-SE (enable)
　　
　　
　　switch-MLS-SE (enable) show mls
　　Multilayer switching enabled
　　!-- By default, MLS is enabled on the switch
　　Multilayer switching aging time = 256 seconds
　　Multilayer switching fast aging time = 0 seconds, packet threshold = 0
　　Current flow mask is Destination flow
　　Configured flow mask is Destination flow
　　Total packets switched = 8
　　!-- Five echos and five replies were sent; the first echo and reply went
　　!-- through the RSM and subsequent were Layer 3 switched, which gives us a total of
　　!-- eight Layer 3 switched packets and two shortcuts.
　　
　　Active shortcuts = 2
　　Netflow Data EXPort disabled
　　Total packets exported = 0
　　
　　MLS-RP IP MLS-RP ID XTAG MLS-RP MAC-Vlans
　　---------------- ------------ ---- ---------------------------------
　　11.11.11.1 00100b108800 2 00-10-0b-10-88-00 11-12
　　switch-MLS-SE (enable)
　　
　　
　　switch-MLS-SE (enable) show mls statistics rp
　　Total packets switched = 8
　　Active shortcuts = 2
　　Total packets exported= 0
　　
　　Total switched
　　MLS-RP IP MLS-RP ID packets bytes
　　--------------- ------------ ---------- ------------
　　11.11.11.1 00100b108800 8 944
　　switch-MLS-SE (enable)
　　
　　
　　RSM-MLS-RP#sho mls rp
　　multilayer switching is globally enabled
　　mls id is 0010.0b10.8800
　　mls ip address 11.11.11.1
　　!-- IP address of MLS-RP
　　mls flow mask is destination-ip
　　number of domains configured for mls 1
　　
　　vlan domain name: sales
　　current flow mask: destination-ip
　　current sequence number: 3150688457
　　current/maximum retry count: 0/10
　　current domain state: no-change
　　current/next global purge: false/false
　　current/next purge count: 0/0
　　domain uptime: 1d00h
　　keepalive timer expires in 8 seconds
　　retry timer not running
　　change timer not running
　　
　　1 management interface(s) currently defined:
　　vlan 11 on Vlan11
　　
　　2 mac-vlan(s) configured for multi-layer switching:
　　
　　mac 0010.0b10.8800
　　vlan id(s)
　　11 12
　　!-- VLANs, interfaces participating in MLS
　　
　　router currently aware of following 1 switch(es):
　　switch id 0050.d133.2bff
　　!-- MAC address of the MLS-SE
　　
　　On the switch, MLS is enabled by default. There is no need to specify the MLS-RP IP address if it is the RSM. However, for an external router acting as the MLS-RP, we need to configure the switch with this IP address by using the following command:
　　
　　
　　set mls include
　　
　　To configure the router, follow the steps below:
　　
　　
　　
　　Enable MLS IP in global configuration:
　　
　　Router(config)#mls rp ip
　　
　　
　　Assign a VTP domain on one MLS interface. The show vtp domain command on the switch provides the VTP domain name; our example is "sales":
　　
　　Router(config-if)#mls rp vtp-domain sales
　　
　　
　　Enable MLS on the interface so that it can participate in the shortcut process:
　　
　　Router(config-if)#mls rp ip
　　
　　
　　Specify a router interface as a management interface, allowing for the MLS-SE and MLS-RP to communicate using a multicast protocol (MLSP):
　　
　　Router(config-if)#mls rp management-interface
　　
　　MLS-RP (RSM)
　　Current configuration:
　　
　　!
　　
　　version 11.3
　　
　　!
　　hostname RSM-MLS-RP
　　!
　　!
　　mls rp ip
　　!
　　!
　　interface Vlan11
　　ip address 11.11.11.1 255.255.255.0
　　mls rp vtp-domain sales
　　mls rp management-interface
　　mls rp ip
　　!
　　interface Vlan12
　　ip address 12.12.12.1 255.255.255.0
　　mls rp vtp-domain sales
　　mls rp ip
　　!
　　ip classless
　　!
　　!
　　!
　　line con 0
　　line aux 0
　　line vty 0 4
　　login
　　!
　　end