Order-aware abstract hops for MPLS LSPs

Junos OS Introduces abstract hops, which are user-defined router clusters or groups that can be sequenced and used for setting up a label-switched path (LSP), similar to real-hop constraints. The router groups are created using constituent lists that include constituent attributes, which is a logical combination of the existing traffic engineering constraints, such as administrative groups, extended administrative groups, and Shared Risk Link Groups (SRLGs). Ordering among the router groups that satisfy the specified constituent attributes is achieved by using operational qualifiers in the abstract-hop definition. A path can use a combination of real and abstract hops as constraints. To configure abstract hops, you need to create constituent lists with traffic engineering attributes, include the lists in the abstract-hop definition, and define path constraints that use the abstract hops.