Alcatel Unleashed

Hi All,

I'm having problem to get the VPLS working over small MTU. So basically i have the following topology :

CPE-A<---> 7210 SAS-Mxp <---> Provider Switch <---> Provider Backbone <---> 7210 SAS-Mxp <---> CPE-B

MPLS and LDP has been established between 7210 SAS-Mxp. I have created VPLS to connecting the CPE on both site. The VPLS is up, the two CPE's can ping each other. But the problem is, we could not run the application like SAP. I think it has something to do with MTU and packet fragmentation.

The provider only provide L2 MTU 1500 byte (maximum). I know this is not suit for VPLS service, since the default service-mtu is 1514. But i don't have other provider who can provide me the link.

So i wonder, is there any parameters i can change to make the topology working?

Thanks in advance, and sorry for my bad english.

If you haven't done so already, reduce the service MTU appropriately for the physical MTU of the path.

Consider enabling control word on the SDPs. It includes a sequence number to help re-assemble frames that have been fragmented across the VPLS service.