It doesn't necessarily mean that MPLS has “higher priority” than OSPF in terms of making routing decisions, but it does indicate how these technologies are being used in your network.

We explain how they relate and work together:

1. OSPF (Open Shortest Path First): It is a routing protocol within the autonomous system that is responsible for discovering and maintaining the shortest paths between devices on an IP network. OSPF works at layer 3 of the OSI (Internet Layer) model and its main function is to determine the best routes through a network using Dijkstra's algorithm to find the shortest path.
2. MPLS (MultiProtocol Label Switching): On the other hand, MPLS operates at both Layer 2 (Data Link Layer) and Layer 3 and is used to direct traffic through labels instead of network addresses. Labels allow MPLS to establish predetermined paths through the network that may be more efficient or better serve certain types of traffic, regardless of the shortest routes calculated by OSPF.

When you traceroute a network that uses MPLS, MPLS labels appear in the results because traffic is being routed through specific MPLS tunnels, and these labels are used to make packet forwarding decisions on the network, which is visible in the traceroute.

Although OSPF may have determined the underlying routes that support these MPLS tunnels, MPLS itself manages how packets are specifically routed within those tunnels, which is why you see MPLS labels in the traceroute.

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MPLS does not have “priority” over OSPF in terms of making routing decisions; rather, it uses the route information provided by OSPF to create a more efficient or suitable path for certain types of traffic.

This may make it seem like MPLS is more dominant, but it's really about how MPLS is applied over the routing infrastructure provided by OSPF.