[c-nsp] ES20+ L3 subinterface or service instance ?

[Tony]

Hi,

We are starting to migrate some connections from SIP400/SPA to ES20+ cards on our 7609's (sup720 w/ SRD4)

The basic configuration we would have on an existing SPA interface would look like something this:

interface GigabitEthernet2/0/1.512
 encapsulation dot1Q 512
 ip vrf forwarding abc
 ip address 10.x.y.z /30
 service-policy output shape_to_carrier_tail_speed


With sometimes OSPF or BGP as PE-CE routing protocol and sometimes static too.

As fas ar I can tell I can just migrate the config exactly as is to the ES20+ card. I also have the option of changing to using a "service instance" (SI) to terminate the interface. I know the SI is more powerful for doing other stuff (like VLAN tag manipulation), but in the case of just terninating a VLAN as a L3 interface is there any reason that one way is better than the other ? As this point I'm planning on leaving it how it is just for simplicity unless there is a compelling reason to change to SI (which I believe would require me to bridge to a VLAN interface to terminate L3 ?).


Thanks,
Tony.