end-user experience. I got my 7960G phones cheap because a company was pulling them all in favor of the newer 7961Gs. The company spent thousands of dollars on new phones because it could not deal with the fact that the line buttons did not light up when the line was in use. A common scenario for this sort of environment is to include a Cisco switch module in the router. The configuration is, for all intents, identical to the one shown in Fig- ure 30-1 and would be drawn the same way, since the switch module connects via an internal gigabit interface in the router and behaves as if it were a standalone 3750. VLANs The first thing we need to do is plan our VLAN environment. Though you can put your phone traffic on the same VLAN as your data traffic, I don't recommend it. The stand- ard VoIP designs from Cisco indicate that the phone traffic should be isolated to a voice VLAN. The VLAN layout is shown in Figure 30-2. Inside .1 192.168.0.0/27 F0/1 .2 F0/0.901 VLAN 901 - Data - 192.168.1.0/24 F0/0.902 2811 w/CME VLAN902 -Voice-192.168.2.0/24 - Figure 30-2. VLAN layout for VoIP network Since our network is pretty simple, we'll create two VLANs on our switch, one for voice and one for data: Small-Office VolP Example SW-3750(config-vlan)#vlan 901 SW-3750(config-vlan)#name Data SW-3750(config-vlan)#vlan 902 I-3750(config-vlan) #name Voice To get the router talking to the switch, we'll need to configure a trunk between them. First the switch: SW-3750(config)#interface GigabitEthernet1/0/10 w-3750(config-if)# description [ R1-PBX Fo/o ] SW-3750(config-if)# switchport trunk encapsulation dot1q SW-3750(config-if)# switchport trunk allowed vlan 901,902 SW-3750(config-if)# switchport mode trunk SW-3750(config-if)# speed 100 SW-3750(config-if)# duplex full W-3750(config-if)# no shut Now we'll configure the router. To make it talk to the switch over a trunk, we'll need to configure one Ethernet subinterface for each VLAN. First the physical interface: R1-PBX(config)#interface FastEtherneto/o R1-PBX(config-if)# description [ Trun