When running a traceroute, should I see any public IP addresses when tracing route from one MPLS point to another MPLS point? So when I do a traceroute from 10.0.0.1 to 10.0.1.1, I see some public IP address in between...
On some of the routers I see this, on others I don't, what does this mean?
Just because they are not in a reserved private IP space does not mean they are public. The private VOIP connection I have to my provider uses "public" IP addresses but there are no routes to the internet. I believe a common reason for this is to prevent addressing conflicts with customers internal ranges.
That depend on your MPLS provider. so there are a patch for the traceroute program, that print the MPLS label using ICMP, if the LSR is configured to affich these labels ( but most of providers don't do). You may test the NANOG traceroute normalized in RFC 4950
The IPs you see are probably the loopback (that is, "a virtual interface that is the first to become active and the last to disappear on a router, usually used for router ID and for management access") addresses of devices through the MPLS network.
I am actually a little bit surprised you see them from your router, that seems to indicate that the MPLS cloud is extended all the way to the CE (customer edge) device.
