This poster was presented at Orange Labs research Days. It summarizes our proposition for the optimization of the expression of segment routing paths. Also as you can see in the simulation result the ELEANOR algorithm slackens considerably the impact of the Maximum Stack Depth (MSD) limitation.

1. journée des doctorants 2016
Software Infrastructure / SWI Rabah GUEDREZ
Efficient Label Encoding algorithm For Segment Routing
(ELEANOR)
6
What is Segment Routing ?
ELEANOR
BGP-LSPCEP
REST
Conclusions
• ELEANOR :
• Gives the minimum label stack to
expressed a segment routing path
(exp.: 1or 2 labels)
• Increases the number of paths that can be
used to route traffic (up to 40%)
• Motivates SP to a faster SR deployment
• Optimizes network resource exploitation by
using path that were unusable
• ELEANOR (renamed SR-LEA) paper
presented at NCA 2016
• Segment Routing architecture leverages the source routing paradigm
• A segment routing path is encoded into the packet header
as a stack of labels
• The longer the path, the bigger the stack
• Hardware limitations on the size of the label stack
=> Some optimal paths can not be used
• How to increase network resource utilization?
• How to reduce the size of the label stack?
Without ELEANOR
Fig 2: ELEANOR implementation
Path computation
Request/Response
Topology
Acquisition
ELEANOR Algorithm
Input: Topological Path
Output: Minimum Label Stack
With ELEANOR
Problem to Solve
Fig 1: Strict path
Results
Fig 3: label stack size variation Fig 4: % of usable topological paths
Divide the topological path into succession of
shortest paths (subpaths)
For each subpath :
• IF size(subpath) >= 2 replace with a Node-SID
• IF size(subpath) == 2 replace Adjacency-SID label