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MPLS Traffic engineering - RSVP Calculation




I have created myself a nice little SP design in GNS 3 with OSPF and BGP, i have now added MPLS to it and setup some L3 VPN's and Layer 2 VPN's.  I am now inspired to look into traffic engineering and get those features incorporated into my little topology.


A problem i came across was the RSVP feature when listing the interfaces bandwidth.  My topology uses VLAN interfaces to interlink the devices in OSPF which means some links traverse multiple layer 2 switches using port channels to reach the other router, does this mean i need to list the RSVP bandwidth on the VLAN interface as the lowest link connection speed (bottleneck) over the path which it will take to reach the other end of the /30?


Am i right in thinking traffic engineering will take over the path selection of packets across my network and bypass the OSPF layer 3 path selection?  I have done abit of research into TE and for some reason this particular topic seems more confusing than the L3 VPN's !


If anyone has any other MPLS features that would be fun to implement in a SP network on GNS3 then let me know and ill look into them!


Best Regards,




Not sure about the first

Not sure about the first question. However, RSVP will create LSP over any path that has desired bandwidth available. If desired BW is not available, the LSP will fail. If lower priority LSP is using bandwidth it will be freed and used by higher priority LSP. On a port-channel interface, each VLAN can be assigned a certain BW or all BW can be available to a  certain set of VLANs.


RSVP Admin Distance is by default better than any IGP AD. RSVP LSP would be preferred hence. 



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