4) Internet Transport Protocols and Satellite Broadband
Submitting Institution
University of AberdeenUnit of Assessment
General EngineeringSummary Impact Type
TechnologicalResearch Subject Area(s)
Information and Computing Sciences: Data Format
Engineering: Electrical and Electronic Engineering
Technology: Communications Technologies
Summary of the impact
While basic communications protocols for the Internet were developed
decades ago, new
requirements such as bandwidth-hungry multimedia and the need for the
Internet to reach the "final
third" of the population create constant demand for improvements. Research
at the University of
Aberdeen has greatly contributed to meeting this demand by influencing the
standardization and
implementation of the Internet Protocol (IP) stack in commercial networks.
New standards for
Internet Transport Protocols and Satellite IP Transmission resulting from
the research have been
implemented in industrial products in Europe and the US, benefitting
industry and millions of end
users.
Underpinning research
In recent years, ever-growing Internet multimedia content has presented
major challenges for
network operators, creating constant demand for improvement. It is
essential that network traffic
coexists with other traffic and that it receives acceptable service
quality, without contributing to
network congestion. Led by Gorry Fairhurst (Professor in Communications
Engineering since
2008), the University of Aberdeen's School of Engineering has completed
important research in
internet engineering, including research in Internet Transport Protocols
(the layer that defines how
the network is shared among applications) and network engineering to
enable broadband satellite
internet access.
Research in Internet Transport Protocols [1-3] on new protocol mechanisms
for congestion control,
focussed on support for networks that include wireless/satellite links.
Using a blend of simulation
and practical investigation, research between 2006 and 2009 comprised
performance analysis,
evaluation and optimisation for: TCP (Transmission Control Protocol); TFRC
(TCP-Friendly Rate
Control); DCCP (Datagram Congestion Control Protocol). It also included
examination of transport
techniques, mechanisms for scalable multicast delivery, explicit
congestion notification, and new
cross-layer radio/transport methods to optimise multimedia performance.
Funding was provided by
research grants and industry contracts.
Fairhurst's research group has over 25 years' experience in Satellite
Networking, and since 2004,
has been a member of SatNEx, a European Network of Excellence (see Section
5, [6] bringing
together 21 leading research establishments in the field. Research in this
area at Aberdeen [4-6]
between 2008 and 2011 proposed and analysed new bandwidth-on-demand
techniques and
studied their interactions with higher layer protocols. This has resulted
in extensive simulation
using an advanced satellite model, developed from industry-funded research
by Astrium UK, and
Thales France, and was made available in 2011 by Aberdeen University as an
open source
contribution to the Network Simulator project ns2, used by researchers
worldwide.
As a part of the research, between 2007-2012 Fairhurst and his group in
Aberdeen designed
techniques for efficient delivery of IP-based TV and radio over the
Internet [4], with particular
attention to high scalability (ability to handle a growing volume of
traffic) including development of
protocol mechanisms for satellite multicast, quality of service, and
cross-layer mechanisms for
resource management [5-6]. EPSRC and funding from Thales (France), Astrium
(UK) [D], and the
European Space Agency enabled the research to underpin development of a
standardized
framework for next generation broadband satellite equipment [6].
A priority across all the areas has been to ensure robust Internet access
over a wide range of
network link characteristics. The new techniques developed through the
research provide the
adaptation needed for users with limited access, especially relevant for
locations at the edge of
reach for wired broadband coverage or where wireless/satellite Internet
access is used.
Applied research on Next Generation Access services (2009 - 2014)
explores the challenges
faced in deploying next generation satellite broadband technology and
developing new services for
the "final third" of the UK population. [6]
References to the research
1. Sathiaseelan, A., Fairhurst,G. "TCP Friendly Rate Control
(TFRC) for Bursty Media Flows."
Computer Communications, SN 0140-3664, 2011.
Investigates a set of new mechanisms for multimedia transport over UDP,
reporting results and
making recommendations on the methods finally published as a part of RFC
5348.
2. Biswas,I., Sathiaseelan, A., Fairhurst, G. "Analysing TCP
for Bursty Traffic." International
Journal of Communications, Network and System Sciences, 2010.
Identified core issues with bursty applications using TCP, and proposed
new techniques to
improve network congestion performance.
3. Fairhurst, G., Eggert, L., "UDP Usage Guidelines for
Application Designers." Internet Society,
RFC 5596, 2010.
Defines techniques that applications should use for UDP — one of the
core Internet protocols.
4. Cantillo, J., Collini-Nocker, B., De Bie, U. Del Rio, O., Fairhurst,
G. Jahn, A. Rinaldo, R.,
"GSE: A Flexible, yet Efficient Encapsulation for IP over DVB-S2
Continuous Generic
Streams". Int. Journal of Satellite Communications, 0737-2884 26
231, DOI: 10.1002/sat.915,
2008.
Describes the design and performance of a new broadcast link design,
finally published as
ETSI TS 102 606.
5. Fairhurst, G., Secchi, R., Yun, A., "Design of the
DVB-RCS2 Higher Layer Satellite
Architecture", Int. J. Satell. Commun. Network. (2013), DOI:
10.1002/sat.1037.
Paper describing work contributed to the DVB-RCS2 HLS Architecture,
published as ETSI TS
101 545-3.
6. Fairhurst, G., Yun, A., "A flexible QoS architecture for
DVB-RCS2", Int. J. Satell. Commun.
Network. (2013), DOI: 10.1002/sat.1026.
Paper describing the work contributed on QoS functions for the DVB-RC2
LL and HLS,
included as a part of ETSI TS 101 545-2 and ETSI TS 101 545-3.
Grants:
1. SATSIX, 1/01/06 → 31/05/08, £210,540, NoE, European Commission.
2. DVB Activity, 1/07/11 → 31/08/11, £161,822, Astrium Ltd.
3. Rural Digital Economy Research Hub, 1/10/09 → 30/09/14, RCUK, Share of
£11.8m, EPSRC.
4. Study of Generic Stream Encapsulation, 1/05/09 → 30/04/10, £43,623,
ESA ARTES.
5. Efficient Networking and MAC Techniques, 4/04/11 → 3/04/12, £74,820,
ESA ARTES.
6. Reducing Internet Transport Latency (RITE), 1/11/12 → 31/10/15,
£371,270, EC FP7.
Details of the impact
(numbering refers to Section 5 unless specified)
Research by Fairhurst and his group has directly benefitted industry, who
have taken up and used
the new standards created from it. Although the commercial gain yielded by
open standards is not
measurable, these standards are hotly contested in competitive markets and
achieve very wide
reach — as in the case of mobile phone or TV standards, which ultimately
affect millions of users.
Other beneficiaries of the research have been the principal Internet
standards authority, as well as
end users of web and mobile technology.
Internet Engineering Task Force
Throughout the impact assessment period, as a direct result of his
research expertise, Fairhurst
has been an active member of the Internet Engineering Task Force (IETF)
[1, 2], the principal
Internet standards organisation. This specifies protocols and current best
practice for Internet
operators in the Request for Comments (RFC) series. These standards ensure
the inter-working of
hardware and software produced by different manufacturers. Throughout the
impact assessment
period, Fairhurst served as Chair of the IP over Digital Video Broadcast
(IPDVB), Datagram
Congestion Control (DCCP) and Transport and Services (TSVWG) working
groups. He became a
member of the Transport directorate, which advises the IETF on transport
standards, in 2009 [3].
Internet Transport Protocols
Since 2008, Fairhurst co-authored a series of ten published IETF standards
documents [1], cited
by 29 other standards documents [1-3]. This work directly benefited
industry: UDP-Lite, RFC5097,
co-authored by Fairhurst, is used in third-generation mobile phone (3GPP
UMTS) equipment
enabling operators such as Ericsson AB [2] to transition to an
internet-based voice service. This
has been implemented in the Linux operating system since release 2.6.20.
Work has also made
significant contributions to UDP (e.g. Section 3 [1, 3]), TCP (e.g.,
Section 3 [2]) and the
development of DCCP (2, 3)).
Satellite IP Networking
Research by Fairhurst and his group directly benefitted the satellite
terminal industry. Techniques
for IP transmission [Section 3 [4]] were applied by leading European space
companies Astrium,
Portsmouth (for a mesh satellite network [4] and Thales (cross-layer
transport optimisation).
Fairhurst was an invited technical expert to the European
Telecommunications Standards Institute
(ETSI) between 2001-2009, where he contributed to the BSM series of
satellite system
specifications [e]. Building on this, Fairhurst et al [Section 3 [4]]
designed the Generic Stream
Encapsulation (GSE) for efficient transport of network packets over second
generation Digital
Video Broadcast (DVB) standards [6, 7]. This was standardized [8], with
work continuing by the
Universities of Aberdeen and Salzburg to specify Extension Formats (RFC
5163, 2008) and
Implementation Guidelines (TS 102 771, 2009). GSE has been implemented in
commercial
broadcast products in Europe [9] and America since 2009, (Newtec's EL470,
EL970; Work
Microwave's SK-IP; GCS's ODG200 and BSR200; Advantec Wireless's AMT75e;
Comtech CDM-840;
KS Transpleneta dpi4502; and Computer Module's DVB Rocket). GSE has
reduced
operational cost for companies delivering satellite IP services [e, f].
Current work within DVB is
adapting GSE to become a standard for all second generation transmission
technologies [9].
In 2009, again on the basis of his research, Fairhurst was co-opted onto
the TM-RCS standards
group on behalf of ESA, the largest standardization initiative for open
satellite communications. He
provided expertise on protocol design and contributed to defining the QoS
[Section 3 [6]] and
network-layer architectures [Section 3 [5]] for the Higher Layers,
published in the DVB Return
Channel via Satellite (DVB-RCS2) specification in 2011 [5, 6]. DVB-RCS2
was successfully
demonstrated by STM, one of the largest privately-held satellite
engineering companies, in their
SatLink platform in June 2011. It has since been implemented by iDirect,
Virginia, USA. Thales-Alenia
Space is currently developing commercial DVB-RCS2 gateway products [6].
Next Generation Access
Fairhurst and his group contributed to design of the Digital Advanced
Rural Testbed (DART, 2012)
and the evaluation of user-experience (2013). This pre-commercial platform
allowed SMEs to
explore technology and economic impacts (ranging from on-demand TV to
wireless access for
government services) with results disseminated to stakeholders and network
operators (e.g.
Avanti, BT). Avanti PLC is using the technology enablers developed in DART
to build new user
services for commercial launch in 2013 [7].
Public engagement
Fairhurst and his team have increased awareness and understanding of
satellite broadband
research through public engagement activities [7[. These included
presentations at the major
annual science and technology festival in Aberdeen "TechFest" (2011) on
the evolution of satellite
broadband, "Satellites in Space", attracting an audience of 150.
Presentations to business and
government representatives at Technology Strategy Board events, including
Innovate (2011,
2013), and the International Telecommunication Union Geneva Conference
(2011) presenting
DART to network operators and government policy makers. Public awareness
was also promoted
through schools visits in 2012 and 2013, and through national radio (e.g.,
interviews with
Townsend, Research Fellow working with Fairhurst, on BBC Radio Scotland's
Out of Doors, 2011).
Sources to corroborate the impact
-
http://www.arkko.com/tools/allstats/godredfairhurst.html
This source corroborates contributions to IETF.
- The Transport Area Director, IETF corroborates contributions to IETF.
- The Chair of Internet
Research Task Force, IRTF will corroborate contributions to IETF.
- A member of EADS Astrium can corroborate contributions to Satellite
Networking.
- The Chairman at TM-RCS can corroborate contributions to ETSI-BSM and
DVB-RCS2.
- The Editor HLS, as part of the TM-RCS Working Group, will corroborate
contributions to DVB-RCS2.
- A member of staff at Avanti Communications PLC can corroborate
contributions to Broadband
Satellite.
-
ETSI TS 102 606, "Generic Stream Encapsulation (GSE) Protocol",
2007.
- DVB GSE Status: http://www.dvb.org/resources/public/factsheets/DVB-GSE_Factsheet.pdf
- ETSI TS 101 545-3, "DVB Interactive Satellite System (DVB-RCS2); Part
3: Higher Layers
Satellite Specification", 2013.