c)#service-policy Ethernet-QoS Chapter VolP Now, I'll apply my policy map to my Ethernet interfaces: R1-PBX(config-if)#int fo/o R1-PBX(config-if)#service-policy output Ethernet-QoS R1-PBX(config-if)#int fo/1 R1-PBX(config-if)#service-policy output Ethernet-QoS If you have subinterfaces, you can apply the SubInt-QoS policy to the subinterfaces: R1-PBX(config-if)#int f0/0.902 R1-PBX(config-subif)#service-policy output SubInt-QoS You cannot apply service policies in the same direction on both the physical interface and the subinterfaces beneath it. The router will complain if you try: R1-PBX(config-if)#service-policy output Ethernet-QoS Attaching service policy to main and sub-interface in the same direction concurrently is not allowed DHCP for Phones Moving on to the router, the first thing we need to do is configure a DHCP scope for our phones. Remember, the phones will all reside in VLAN 902 and have an IP address in the 192.168.2.0/24 space. To keep the phones from grabbing the IP addresses of the routers and other critical systems, let's keep the DHCP scope within the .129-.222 range: ip dhcp excluded-address 192.168.2.1 192.168.2.128 ip dhcp excluded-address 192.168.2.223 192.168.2.255 ip dhcp pool Phones network 192.168.2.0 255.255.255.0 option 150 ip 192.168.2.1 default-router 192.168.2.1 dns-server 192.168.1.200 192.168.1.205 The command option 150 ip 192.168.2.1 allows the IP phones to learn the address for the TFTP server. The phones need somewhere from which they can retrieve firm- ware and configuration files. We'll be configuring our 2811 router to be the TFTP server, SO I've specified the voice VLAN's IP address on the router to be the TFTP server address. We could also use option 66, which would allow us to specify a DNS- resolvable name. TFTP Service When a Cisco IP phone boots, it talks to the switch via CDP to determine things like how much power it requires (if we're using PoE), which VLANs it should use, and SO on. It then requests an IP address, a TFTP server, and, once connected, some informa-