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New Member

Multilink MTU size


I am running into an issue with the call quality from our China office to the US - it seems I need to adjust the MTU size for the packets and call quality to work - my question is we have  a multilink to our WAN - do I need to change the MTU on each interface within the multilink as well as the multilink to make it work.  I changed just the multilink and my MPLS circuit dropped.


New Member

Multilink MTU size

i dont think you need to play with MTU, specially on multilink itself,

on actual T1/E1 MTU should be standard 1500.

What you need to check is Queueing strategy on your multilink and actuall T1/E1, try Faire-queue if its FIFO

Super Bronze

Multilink MTU size


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If your seeing call quality issues, that's often mitigated by using QoS features, including those on MPLS clouds.  (NB: MPLS QoS features are also often dependent on what your MPLS vendor supports [and what you're willing to purchase].)