description cross connect isdn interfaces addrouter r1 int ser1 ser - $1a$ $1b$ ! vrf def v1 rd 1:1 exit int ser1 enc isdn isdn mode dce vrf for v1 ipv4 addr 2.2.2.1 255.255.255.0 ipv6 addr 4321::1 ffff:: exit ! addrouter r2 int ser1 ser - $1b$ $1a$ int ser2 ser - $2a$ $2b$ ! int ser1 enc isdn connect ser2 exit int ser2 enc isdn exit ! addrouter r3 int ser1 ser - $2b$ $2a$ ! vrf def v1 rd 1:1 exit int ser1 enc isdn isdn mode dce vrf for v1 ipv4 addr 2.2.2.2 255.255.255.0 ipv6 addr 4321::2 ffff:: exit ! r1 tping 100 30 2.2.2.2 vrf v1 r1 tping 100 30 4321::2 vrf v1 r3 tping 100 30 2.2.2.1 vrf v1 r3 tping 100 30 4321::1 vrf v1