Download Slides

Network and Capacity Planning
in SURFnet6
(first results)
Ronald van der Pol
<[email protected]>
TNC2009, 8-11 June 2009, Malaga, Spain
SURFnet6
Hybrid network
IP routed & lightpaths
Over 8800 km dark fiber
Cross border fibers
Hamburg
Münster
Aachen
Over 200 lightpaths
TNC2009, 8-11 June 2009, Malaga, Spain
SURFnet6 Lightpath Usage
TNC2009, 8-11 June 2009, Malaga, Spain
Lightpaths in SURFnet6
Type
Total
150
Mbps
300
Mbps
450
Mbps
600
Mbps
750
Mbps
900
Mbps
1
Gbps
10
Gbps
unprotected
43
7
0
0
0
0
0
32
4
protected
87
23
3
1
3
0
0
56
0
redundant
76
25
10
2
3
0
2
34
0
TNC2009, 8-11 June 2009, Malaga, Spain
Lightpath Duration and
Provisioning Activity
TNC2009, 8-11 June 2009, Malaga, Spain
Planning Tool
Used for lightpath planning
In-house built tool, open source
Written in Java (previous version written in Perl)
Web application based on JSP and Servlets
Runs on Apache Tomcat
Dijkstra Shortest Path for unprotected lightpaths
Suurballe Shortest Cycle for protected lightpaths
Adapted Dijkstra Algorithm for (SRLG) contraint based
protected lightpaths
Configuration file for defining metrics
Cost per interface or link (based on regular expressions)
Cost based on link utilisation
TNC2009, 8-11 June 2009, Malaga, Spain
Planning Tool Building Blocks
TL1 Toolkit Perl script extracts topology from network
Always up to date information
Neighbour information based on section traces
Network topology stored in NDL format
Network Description Language
TL1 Toolkit Perl script extracts configuration data from
network
Retrieves resource usage of all currently configured
lightpaths from the network
All data is stored in MySQL database
MySQL database also contains lightpath reservations
(resources reserved, but not configured in network yet)
TNC2009, 8-11 June 2009, Malaga, Spain
Planning Tool Architecture
TNC2009, 8-11 June 2009, Malaga, Spain
Planning Tool Algorithm
1.
2.
3.
4.
5.
Read NDL topology and build mathematical graph
Read current resource usage from database
Prune links with too little available bandwidth from graph
Run path finding algorithm
Reserve resources in database
TNC2009, 8-11 June 2009, Malaga, Spain
Planning Tool User Interface
TNC2009, 8-11 June 2009, Malaga, Spain
Path Finding and SRLG
SRLG: Shared Risk Link Group
Fibers going through the same duct
Wavelengths going over the same fiber
In general, finding a protected path with SRLG constraints
is an NP-complete problem
SURFnet6 has topology with several rings starting and
ending at two locations in Amsterdam
Most SRLGs are wavelengths over the same fiber
Limited number of possible paths, therefore path found in
less than a second
TNC2009, 8-11 June 2009, Malaga, Spain
SURFnet6 DWDM Topology
TNC2009, 8-11 June 2009, Malaga, Spain
Analysis of SURFnet6
SURFnet6 contains almost 300 lightpaths
Question: are these lightpaths optimally routed?
First lightpaths were planned manually
Network evolved (links added, more capacity)
Protected lightpaths found with 2x Dijkstra (Suurballe
algorithm very recent addition)
Analysis with two strategies:
Replanning all lightpaths on empty network
Remove and replan each lightpath (keep all other lightpaths
the same)
TNC2009, 8-11 June 2009, Malaga, Spain
Analysis Results
Potentially 47 lightpaths in SURFnet6 are not optimally
routed
There is no difference between rerouting on an empty
network and per lightpath rerouting
Further detailed analysis needed
Example of some optimisations:
ID
# interfaces After reroute
(existing network)
After reroute
(empty network)
2030LE 6
4
4
2032IE
6
6
2112LP 12
10
10
2098LP 16
14
14
8
TNC2009, 8-11 June 2009, Malaga, Spain
Thank You
Ronald van der Pol
[email protected]
http://nrg.sara.nl/
Acknowledgements
Freek Dijkstra (SARA)
Rob Juffermans (TU Delft)
Wouter Huisman (SURFnet)
Funded by
GigaPort2
SURFnet
TNC2009, 8-11 June 2009, Malaga, Spain