Mine

        option vlan_id code 132 = int32;

subnet 192.168.1.0 netmask 255.255.255.0 {
        option routers 192.168.1.1;
        option domain-name-servers 192.168.1.1;
        option broadcast-address 192.168.1.255;
        option ntp-servers tic.nrc.ca;
        option time-servers tic.nrc.ca;
        option time-offset -18000;

# matches any polycom hardware (vendor MAC 00:04:f2):
        class "phones" {
                match if substring(binary-to-ascii(16, 8, ":", hardware), 2, 6) = "0:4:f2";
                }

# phones
        pool {
                option tftp-server-name "192.168.1.1";
                option vlan_id 3;
                max-lease-time 28800;
                range 192.168.1.80 192.168.1.99;
                allow members of "phones";
                }

# regular computers
        pool {
                option domain-name "domain.dom";
                max-lease-time 28800;
                range 192.168.1.200 192.168.1.254;
                allow unknown clients;
                deny members of "phones";
                }

}