Straight Forward MTU question

RouterOS Forwarding Protocols
1

Hello
I know this is asked before but I am confused.

See below network :

|Router A| —VPLS— |RouterB| --ethernet--

PPPoE s has to be terminated on Router A

Please tell me the following minimum values to avoid packet fragmentation + maximum VPLS performance.

  1. Router A MPLS interface MTUs
/mpls interface>
  1. Router A VPLS interface MTU
/interface vpls> set advertised-l2mtu= ??
  1. Max MRU and MAX MTU values for PPPoE Server
 2   service-name="service3" interface=vpls1 max-mtu=?? max-mru=?? 
     mrru=disabled authentication=pap,chap,mschap1,mschap2 keepalive-timeout=10 
     one-session-per-host=no max-sessions=0 default-profile=profile1

I appreciate any answers.

2

Hi,

  1. 1526
  2. 1500
  3. 1492/1492

This is how it works for me.

saludos
Bernardo

3

This actually depends on your hardware, and max l2mtu.

4

As far as MPLS mtu goes, here are the numbers you need for 1500 bytes frames.

1526 - To run untagged VPLS
1530 - To run tagged VPLS

As far as PPPoE, it requires 8 bytes of overhead for the PPP portion.