OpenFlow in the access –
pushing OpenFlow switches to
the last mile
Richard G. Clegg (email@example.com)
University College London, Department of Electronic Engineering
Talk to Brazil/UK conference 2014
(Prepared using LATEX and beamer.)
University College London – Electronic Engineering
Communcations and Information Systems Group – 6
academics, 20 researchers, 10 PhD students.
Optical Networks Group and Photonics Group – both similar
The ALIEN project
ALIEN – Expanding the availability of OpenFlow
Get OpenFlow working on new types of devices. Expand use of
OpenFlow by making it useful for new platforms.
Programmable platforms – NetFPGA and similar.
Access networks – e.g. GEPON and DOCSIS.
Optical devices – require OpenFlow extensions.
The GEPON (Gigabit Ethernet Passive Optical Network)
ONU ONU ONU
End User machines
Getting OpenFlow on GEPON
Want to make whole system of switch, OLT, splitter ONU
present as single massively distributed OF switch.
Problem with making GEPON OpenFlow capable:
Proprietary device, no knowledge of chips or drivers.
Not intended as programmable.
ONU cheap low power consumer unit.
Make use of fact that OLT usually needs switch before it
Give OLT Open Flow capable front end switch (xdpd on
OLT can switch to ONU on VLANs.
Use a mapping to VLANs in lower level open ﬂow switch.
Controller sees only higher level abstract switch.
The GEPON with OpenFlow
OpenFlow enabled GEPON
Note – approach is generic – could work for many access
Another partner is working on the generic approach of
surrounding the non OF device with OF switches.
My oxther work on optical networks and SDN
Non Orthogonal (Spectrally Eﬃcient) FDM
Traditional OFDM ﬁxed relationship between symbol period and
frequency separation. “Squeezing” results in interference but can
recover the signal. Spectral eﬃciency increased up to 20% –
software test done, hardware tests underway.
A practical system for improved eﬃciency in FDM RG Clegg, S
Isam, I Kannaras, I Darwazeh, IET Communications 2013.
SDN for network resilience
Often multiple routes from data centre to destination on Internet.
OpenFlow used to tag packets at machine ingress. Tags used to
route packets at datacentre egress. Quick failover in case of path
Software-deﬁned network support for transport resilience JT
Araujo, R Landa, RG. Clegg, G Pavlou, IEEE/IFIP NOMS 2014
Conclusions – Optical work at UCL
In ALIEN we are working to get OpenFlow working on optical
access networks. We are also testing CCN (ccnx) over the OFELIA
testbed over a number of OpenFlow switches. Large-scale
Other work at UCL
There is a large amount of other optical work at UCL, optical
network testbeds, high end passive optical networking.