GRE, VoIP with MLP LFI

[TOBY JESSUP]

Customer wants fractional T1 with GRE and VoIP. If the ISP edge supports it, can we use MLP framing on the low speed T1 access lines to achieve LFI and fragmentation and avoid using IP MTU (PMTUD) for fragmenting?

IPsec is not required.

Any other tricks to accomplish low-speed fragmentation with GRE and avoid using IP MTU?

[roluce]

One work around is to adjust the mss size.

ip tcp adjust-mss 730

is a good starting figure, see RFC 3390 for more details.

This doesn't eliminate fragmentation, but it it keeps TCP (which is usually the lion's share of traffic) from sending packets that will be fragmented by the router.

Rob