Fault-Tolerant OpenFlow-based Software Switch Architecture with LINC Switches for a Reliable Network Data Exchange a presentation by Gandhimathi Velusamy, U. Houston at the US Ignite ONF GENI workshop on October 8, 2013

1. Fault-Tolerant OpenFlow-based Software
Switch Architecture with LINC Switches for
a Reliable Network Data Exchange
Gandhimathi Velusamy
University of Houston

2. GOAL
Software Switches in Data center Networking

3. LINC- A Complete OpenFlow Software Switch
 Introduced by FlowForwarding.org as a open
source
 LINC supports OpenFlow specifications 1.2 and
1.3
 Supports OF-Config 1.1
 Works in user space
 Written in Erlang language

4. Erlang Features
 Has massive concurrency support
 No shared resources
 Uses messages to communicate between processes
 Message passing makes scalable easier and improves the
efficiency
 Utilizes multicores available on the computer
 Distribution property of Erlang OTP platform is used to
built fault tolerant and distributed applications.
 No down time

5. Topology on GENI

6. Failover and Take over
S1
Running
S2
Started
S3
Started
S2
Running
S3
Started
S1
Down
S2
Down
S3
Running
S2
Down
S1
Running
S2
Down
S3
Exit
{kernel,
[{distributed, [{linc, 5000, ['linc@S1', 'linc@S2', 'linc@S3']}]},
{sync_nodes_mandatory, ['linc@S1', 'linc@S3']},
{sync_nodes_timeout, 5000}
]}

7. Tasks to be done
How to reduce the number of packets dropped when the takeover
switch is getting connected with controller and waiting for the
controller to send flow entries.
 Use of buffers to store the packets in the switch ports. OF-Config
to set buffer?
 Controller can have a copy of the flow entries stored permanently
and can send to the takeover switch when a packet-in happens.

8. Fault tolerant Distributed Switching system

9. Bibliography
1. www.FlowForwarding.org
2. McKeown, Nick, Tom Anderson, Hari Balakrishnan, Guru Parulkar, Larry Peterson, Jennifer
Rexford, Scott Shenker, and Jonathan Turner. "OpenFlow: enabling innovation in campus
networks." ACM SIGCOMM Computer Communication Review 38, no. 2 (2008): 69-74.
3. Armstrong, J. 2010. Erlang. Commun. ACM 53, 9 (Sep. 2010), 68-75.
DOI=http://doi.acm.org/10.1145/1810891.1810910
4. Fonseca, Paulo, Ricardo Bennesby, Edjard Mota, and Alexandre Passito. "A replication component
for resilient OpenFlow-based networking." In Network Operations and Management Symposium
(NOMS), pp. 933-939. IEEE, 2012.
5. http://www.erlang.org/doc/apps/erts/erl_dist_protocol.html
6. Hebert Fred, “Learn You Some Erlang for Great Good”, 2013, ISBN 9781457172427.