1. Prof.Veeraraghavan Prof.Karri Haobo Wang: haobo_w@photon.poly.edu
Hardware Accelerated Signaling and its Application in Fast Network Restoration
Prof.Veeraraghavan
Prof.Karri
Haobo Wang:

2. Background What’s signaling? Primarily implemented in software
Signaling protocols are used in connection-oriented networks to set up and tear down connections.
Primarily implemented in software
Complexity and the requirement for flexibility
What we pay is the performance
Hardware accelerated signaling
Why? 100x-1000x speedup
How? FPGA+Hardware/software Codesign

3. Which is better? “Thin” hardware signaling engine
Simple signaling addressed to single application
Optical Circuit Signaling Protocol – OCSP
Simple, for SONET network only
Hardware accelerated signaling engine
“Panacea” signaling – RSVP-TE for GMPLS
Complex but covers all connection-oriented networks
Hardware/Software Codesign
Time-Critical functions->hardware
Non-Time-Critical functions->software

4. Network and node view

5. Architecture of Prototype Board

6. Hardware Signaling Accelerator

7. Applications of Hardware signaling
High throughput
Support large scaled core switches – TCP switching
Low call setup delay
Fast restoration after network fails
Illinois, May 1988, a fire at a local exchange center caused the loss of service to 35,000 residential telephones
Today, data traffic prevails, more sensitive to loss
One single fiber may carry T(era)bps of user traffic!
Network survivability is essential

8. Trade-off of different recovery schemes
Fast
Recovery delay
Slow
Bad
Good
Resource utilization
Protection
Resource reserved in advance
Linearly/Ring topology
LAPS or SHR
Line switching
The failure is addressed locally, point-to-point
Restoration
react to failure dynamically
Mesh networks
Path switching
The failure is addressed globally, end-to-end
We want both! High resource utilization and low recovery delay
Dynamic re-routing in mesh networks

9. Dynamic re-routing in Mesh network
A disjoint back-up route is pre-calculated, but not allocated
Routing table has entries for backup route
Hardware signaling helps to set up backup path rapidly
May be blocked  A B C D E F

10. Analysis and simulation (ongoing work)
A 13-node, 22-link sample network, average number of hops on primary path is 2.4, on secondary path is 3.5.
Analysis of dynamic provisioning (M/D/1/∞)
Simulation of dynamic re-routing
When link/node fails, all affected paths must be re-routed simultaneously. We use OPNET to model the dynamic re-routing behavior.