SR-MPLS
SR-MPLS – Fallback for inetcolor.0
1. Intro This is a continuation of the previous post: SR-MPLS – Static colored LSP. There we configured a colored LSP and we saw how the next-hop is installed in the inetcolor.0 table. But, what will happen if that LSP goes down? With no more valid next-hops in the inetcolor.0 table the traffic will be […]
SR-MPLS – TI-LFA
1. Intro Loop-free alternate (LFA) and remote LFA have been used to provide fast-reroute protection for several years. With LFA, a point of local repair (PLR) determines whether or not a packet sent to one of its direct neighbors will reach its destination without looping back through the PLR. In a typical network topology, perhaps […]
SR-MPLS – Anycast
1. Intro An IGP anycast segment is an IGP prefix segment that identifies a set of routers. An anycast segment enforces forwarding based on the equal-cost multipath-aware shortest-path toward the closest node of the anycast set. Within an anycast group, all the routers advertise the same prefix with the same SID value, which facilitates load […]
SR-MPLS – Computed LSP
1. Intro Another way to create an LSP is to calculate the path dynamically based on a set of traffic engineering constraints. This option uses a version of the CSPF algorithm (similar to RSVP), called Distributed CSPF (D-CSPF). The name reflects the fact that the protocol can be run on any router in the network, in contrast […]
SR-MPLS – Static colored LSP
1. Intro The ingress route of the colored LSP is installed in the inetcolor.0 or inet6color.0 routing tables, with destination-ip-address, color as key for mapping IP traffic. We will use the same test topology from the previous posts: The initial config is simple: 2. Colored LSP We want to transform our source-routing-path R1-TO-R8 to a […]
SR-MPLS – Static non-colored LSP
1. Intro The segment routing architecture enables the ingress devices in a core network to steer traffic through explicit paths. You can configure these paths using segment lists to define the paths that the incoming traffic should take. SR is a control-plane architecture that enables an ingress devices in a core network to steer traffic […]
SR-MPLS – Basic Config
1. Intro Segment Routing is also known as Source Packet Routing in Networking (SPRING), and it comes in two flavors SR-MPLS and SRv6 In a segment-routed network, source routing enables the first router in a path to calculate the end-to-end path. The source router can then write a series of MPLS labels or IPv6 addresses […]