FIRST: Future Internet –
A Role for Satellite Technology
Gorry Fairhurst
University of Aberdeen
School of Engineering
Aberdeen, UK
Bernhard Collini-Nocker
University of Salzburg
Department of Computer Sciences
Salzburg, Austria
Luca Caviglione
CNR – ISSIA (Genoa Branch)
Genoa, Italy
Abstract— This paper identifies key research issues and
technologies that we envision will be important to the continued
evolution of satellite networking and its integration as a core
component of a Future Internet that offers reliable, robust and
pervasive networking and access to network services.
Keywords—Future Internet, Satellite
I.
Although there are trends, there is not just a single vision
for what will comprise the Future Internet. Rather, the concept
of the Internet of the Future means many things to many
people:
•
An Internet by and for people/communities (breaking
the digital divide, addressing new and common user
expectations and needs, facilitating everyday life of
people, communities and organizations, breaking the
barriers/boundaries between information producer and
information consumer, allowing creation of any type of
business regardless size, domain and technology, etc.),
•
The Internet as common substrate for knowledge and
society, extending the role of digital communication, as
a fundamental component of modern society.
•
An Internet of things (interconnecting a wide variety of
networked objects, devices, and systems – much more
than computing machines, e.g. ambient networks),
•
An Internet of services (intelligent, proactive and not
only reactive services e.g. domestic networks).
INTRODUCTION
The Internet has been extremely successful in allowing the
equipment at the network edge to evolve and reflect changes in
technology and the patterns of use. Over the next decade this
pace is expected to quicken, and we expect there to be
significant changes in the way the Internet is used. New
markets for converged applications/services are already
emerging: Voice over IP (VoIP) is now common, Internet TV
is emerging, inter-network roaming and location-based services
are becoming available [1].
We foresee a future Internet where access to network
capacity and services is globally available “anywhereanytime”, and where it becomes a fundamental service that
communities use and rely upon [2]. We see an Internet that
continues to grow, both in the number of connected systems
and the number of packets exchanged. Traffic patterns with
very different characteristics are becoming common, as a direct
consequence of the increasing range of services that are
supported. Moreover, the Internet (in the broader sense of a
“pool of technologies”) is commonly recognized as the
preferred environment to deliver services vital to business, to
home-produced content and an increasing diversity of new
applications, including some important example of teleeducation, tele-medicine and emergency management [3].
We expect that the current edge of the network (e.g.
services to people’s homes or companies) will often be just one
hop in the Internet of the future. The trend to connect more and
more devices will also accelerate, facilitated by the increasing
diffusion of IPv6. In the not so distant future, the Internet will
therfore connect vast numbers of tiny devices integrated into
appliances, sensors, actuators, and a vast range of previously
independent systems. These new devices may challenge
traditional understanding of network topology, user control,
and modes of operation.
978-1-4244-1948-7/08/$25.00 ©2008 IEEE
The Internet of the future will not only benefit from
significant technical changes on horizon, but also needs to
evolve to address emerging concerns, including routing
scalability, the role of middleware, the emergence of
middleboxes within the Internet architecture, a growing desire
for improved mobility, weaknesses in the security architecture,
identity management, net neutrality, and more.
The rapid advances in technology that underpin the Future
Internet have been accompanied by a significant change in
individual user expectations. There is evidence of a growing
dependency on the Internet for fundamental services, such as
telephony, business transactions, and to support the
infrastructure of society. This, in turn, has fueled a demand for
a more dependable and trustable solution, and a need to allow
rapid composition of new services, in some cases personalized
to individual users or enterprises.
Key questions are posed for the satellite and Internet
industries: “How will the future Internet and satellite relate to
one another?” Specifically, “How can interoperability be
seamlessly provided? And what needs to be changed to make
this happen?”
IWSSC 2008
The remainder of the paper is structured as follows: Section
II showcases the key benefits of adopting satellite
communications to deliver a ubiquitous networking to the
Internet. Section III presents the range of opportunities
unleashed by the adoption of satellites as a core technology for
the future Internet. Section IV concludes the paper.
Internet access (e.g., Inmarsat BGAN). Besides, recent
advances in the DVB-RCS+M standard will allow also
to implement these services in some mobile
environments.
•
Satellite technology continues to support residential
Internet access. Current trends suggest this market will
remain important, but niche, in areas were there is no
well-developed wired (e.g. xDSL) or terrestrial
wireless (UMTS, WiMax, LTE, etc) infrastructure. In
rural communities with low population density and no
opportunity to access terrestrial broadband connectivity
for the foreseeable future, collective low-cost access
may be provided using satellite delivered via wireless.
•
Satellites provide a primary platform for wide-area
multicast and broadcast. Satellite is used not just for
the “last mile” broadcast of TV to people’s homes, but
in contribution and distribution networks, outside
broadcast and satellite news gathering. The volume of
use is expected to expand with the update to HDTV
services to mass consumer markets. Multicast data
services can leverage the same characteristics. Future
developments include ultra-high definition and 3D-TV,
with services increasingly a convergence with Internet
content.
•
Satellites provide communications links to a variety of
space platforms. Satellite offers a unique role in
environmental
monitoring,
and
satellite
communications support a variety of science missions,
including inter-planetary communications.
•
Satellite communication is environmentally neutral,
allowing for solar energy operated in-space devices
and least penetrating radiation.
II. SATELLITE COMMUNICATIONS
Satellite is not a new Internet bearer technology. It is
already an integral part of today’s Internet infrastructure. Any
communication system requiring ubiquitous access to the
Internet, must consider satellite as a part of the portfolio of
bearer technologies needed to support the network. No truly
worldwide connectivity can be achieved in absence of a
satellite component.
Over the past decade, there has been significant
development of new technology for broadband satellite access
and broadband-related services and applications. Many users
across the globe now rely on satellite technology to provide
their Internet service, and this is likely to continue for a variety
of reasons. Specifically:
•
Satellite links offers a reliable and dependable service.
Satellite systems have long been effectively used as
primary fallback for major links to assure resilience to
infrastructure failure.
•
Corporate networking remains an important world
market for satellite operators. Government and military
customers continue to contribute a significant sector of
this market. Air traffic management and emergency
services are two other sectors that could leverage this
technology. In this context, satellite systems (such as
DVB-RCS in Europe) often offer a single point of
contact for all communications that can support strong
service guarantees (including QoS and flexible
bandwidth provisioning). This market is smaller in
Western Europe, where terrestrial networking
competition is stronger, than in the USA, but it can be
very promising and in other places (South-America,
Africa, Eastern Europe, India and China) where
satellite communications are being deployed.
•
Satellite can provide rapid deployment of
communications solutions, offering a quick response to
customer needs. Systems can be ready in matter of
minutes or hours in any location covered by the
satellite footprint e.g. to supporting events,
communications to engineering teams, exploration,
emergency services, tele-medicine, or service
restoration following a disaster.
•
Satellite offers an efficient overlay network to
interconnect terrestrial wireless networks, serving as a
gap-filler for mobile users, and as complementary
ground components.
•
Satellite is uniquely positioned to support mobile users
who require communications on the move to aircraft,
ships and vehicles. Military (X-band) and maritime
operations (S and L-Band) have long been supported
by specialized satellite systems, which now offer
Many major markets for satellite communications are
outside of Europe, therefore European satellite industry needs
to compete on a global scale. Competition within Europe is
also strong from next-generation systems developed outside of
Europe, e.g. Spaceway, WildBlue, IPstar. All have growing
numbers of customers, and benefit from economies of scale.
In contrast to vendor-specific solutions, the communicators
industry in Europe has established a reputation for strongly
pursuing high-quality provider-independent standards that
continue to achieve world-wide acceptance. One example is the
series of cellular phone standards produced by the third
generation partnership project (3GPP) and published by ETSI
(and which recently include satellite components). ETSI also
publishes a world-leading series of standards from the Digital
Video Broadcasting (DVB) project, most notably the DVB
satellite specifications. DVB (with the support of the European
satellite industry and the European Space Agency) has also led
the field in standardizing vendor-independent bi-directional
Internet communications, in the form of the DVB-RCS system
and the recently adopted standard for broadcast to mobile
devices DVB Satellite Handheld (DVB-SH).
ETSI sets standards and publishes technical documentation
for a range of networking issues for IP-based satellite systems
(in the Broadband Satellite Multimedia group), emergency
services (SATEC), UMTS and IMT-2000, and Mobile Satellite
Systems (e.g. MSS).
Regulatory issues are also fundamental to the satellite
industry to ensure proper function of networks that span many
countries and time zones. In this perspective, achieving the
harmonization of the regulatory frameworks is a key goal for
the future, to promote fair regulation for ground components
and spectrum usage. This will help remove barriers to
deployment and ensure the allocation of sufficient spectrum for
all satellite communication applications and services.
A. Future Communications Space Segment
Satellite space segment needs to be planed and provisioned
in advance of new services. From the creation of an initial
satellite communications concept to launch of a satellite can
take as much as 10 years, and a minimum of 4 to 5 years.
Significant advances in the payload design for
communications satellites will extend the satellite lifetime,
while at the same time, reconfigurable payloads will provide
the flexibility to reconfigure deployed satellites, permitting new
services to evolve after satellite launch, and open the way to
more advanced processing, including on-board regeneration of
signals affording smaller and lighter ground terminals with
greater communications reach and presenting opportunities for
dynamic spectrum management and cognitive radio. Hybrid
payloads may combine the advantages of the different designs
within a single satellite.
Satellites operating at all frequencies are increasingly
taking advantage of larger antennas (supporting multiple spot
beams & beam-forming). The next generation of
communications applications may be expected to offer
increased capacity using higher frequency bands (Ka-band (2030 GHz), V-band (40-75 GHz) and W-band (80-110 GHz)),
increasing availability of bandwidth, minimising the size of
terminals and increasing frequency re-use – at the penalty of
more challenging link propagation conditions.
On-board switching allows satellites to forward packets
between spot-beams providing network-oriented functions that
could also improve integration with the Internet. In the future,
high-rate inter-satellite links may be used to extend the range of
coverage beyond that reachable from a single satellite or be
used to enable efficient new designs linking groups microsatellites or swarms of nano-satellites, or to link satellites to
airborne platforms (e.g. High-Altitude Platforms (HAPs) which
provide low-cost Beyond 3G (B3G) Voice over IP (VoIP)
communications to ships and airplanes).
Based on these advancements, and new techniques
expected to emerge in the short-term, there is potential to
develop a new generation of advanced satellite based
communication system. Such a system could provide
significant increases in capacity, usability, cost/effectiveness,
flexibility and integrate communications with other services
(such as geo-location, sensing, etc.) to establish unique
capabilities that can be used to pioneer new services and
applications.
B. Future Ground Segment Developments
The cost factor is important in any commercial
communications system. For satellite terminals the operational
cost comprises a combination of many components (cost of
equipment related to volume), installation and operation
(impacted by regulatory issues), and space-segment costs
(amortized over the lifetime of the satellite).
There have been significant advances in the techniques
employed in satellite terminals within the past decade, both in
terms of RF technology, waveforms and networking stacks.
Waveforms need to continue to evolve (power and bandwidthefficient for continuous and burst modulation, adaptive coding
and modulation, frequency re-use, advanced resource
management, etc.).
Future terminals need to be easily deployable (with
automated antenna pointing where possible). Selfconfiguration is desirable, and improved open management will
ease integration into the wider network. Together these
advances increase functionality, reduce terminal size, and
provide higher transmission rates (especially when utilizing
higher frequency satellite payloads). Research needs to
continue to support these trends to drive-down costs and seek
higher spectral efficiency. Satellite operations may be
simplified by automating transponder capacity request &
negotiation, easing integration with terrestrial services.
As terminal size decreases and mobility becomes more
common, advanced methods will be needed to combat the
effects of interference from and to other services (e.g. multiuser detection and interference cancellation schemes). This will
allow more efficient spectrum use by reducing the frequency
reuse pattern, enable new transmission modes with a higher
spectral efficiency, and may mitigate some of the risks of
antenna mis-pointing.
Following the trend in software-defined radio,
mobile/transportable terminals may be given the ability to
switch between a range of waveforms, allowing them to move
between types of network. Future Internet services should be
agnostic to the diversity of access technologies (including the
use of satellite). Handovers could become much more dynamic,
and dependent on the service required, with systems
automatically choosing the best connectivity at the current
time, taking advantage of spontaneous and opportunistic
networking opportunities. Satellite may be used when and
where this offers an advantage over other bearers.
C. Networking Evolution
Recent years have seen the Internet protocol suite appear as
the networking technology of choice. Satellite needs to be seen
as one bearer technology in the evolving heterogeneous
Internet. It is essential that protocols and services are able to
accommodate the wide range of network characteristics that
will be presented in the next generation Internet. To achieve
this, satellite operators and equipment vendors must participate
in setting Internet policies, specify architectures, and define
protocols. Early inclusion is essential to assure that the future
Internet will interwork over satellite (new mobility paradigms,
security frameworks, adaptive transport protocols, etc., must
accommodate the effects of satellite delay and resource
management, and the advantages of wide-area multicast).
of operation simultaneously delivering data to multiple people
(even if this data is subsequently consumed at different times).
A visible proportion of network operators are now
undertaking some form of IPv6 deployment and much of the
technology required to deploy IPv6 in terrestrial environments
is operationally ready. IPv6 requires changes to the design of
the network interface and control protocols. Research and
development is therefore needed to seamlessly integrate IPv6
with satellite systems [7]. However, IPv6 is not the solution to
the wider question of the shape of the future Internet. It is just
one component needed to evolve away from the limitations of
the current Internet and to open the path towards a more
pervasive, more accessible, more flexible platform on which
can be hosted a wide range of new applications and services.
Satellite based broadcast/multicast capabilities are also
interesting for distributing control information (security
policies, routing signaling) to network equipment/terminals
(e.g. mobile ad-hoc networks).
The future Internet needs to assure the performance of
applications and ensure equitable sharing of available network
capacity. Many current TCP-based services rely on rateadaptive and congestion-control methods at the Internet
transport layer. Some applications, e.g. streaming also provide
similar methods. New methods are emerging that are expected
to provide more control of the policies used to implement
services and that are expected to efficiently share capacity, able
to mitigate the effects of congestion for a range of services
(adaptive multimedia, web and file sharing, background download and peer-to-peer) [4]. Work is needed to develop these
advanced transport methods and ensure their widespread
adoption across all network technologies, and specifically to
ensure favorable performance and efficiency over satellite.
Future systems need to be integrated with the satellite
broadband segment into the Future Internet harmonizing
interfaces and services to both wired and wireless networks
(e.g. WiMAX, WiFi and TETRA). Hybrid satellite/terrestrial
wireless will allow satellite to effectively contribute to
providing cost-effective broadband to fixed, nomadic and
mobile. Nevertheless, this is also a key feature to effectively
support communications for disaster recovery operations,
emergencies and to successfully join distant rural areas [5].
Roaming among different communications networks will
be key, with opportunities for combining service elements from
a range of technologies to innovate new services and greater
user choice.
Besides integrating the satellite terminal as a part of a wider
Internet, satellite systems can also provide flexible access to a
wide range of “non-traditional” networks, such as SCADA
(Supervisory Control And Data Acquisition) sensor nets,
scientific space missions (such as environmental monitoring),
deep space networks, etc. We expect these roles to continue for
satellite systems (although the requirements differ significantly
from broadband Internet in terms of operating cost, traffic, and
terminal design) and that these will also take advantage of
developments in communications technology, and we expect
increased integration of these specialized networks with the
Internet, as technology matures.
The wide-area coverage of satellite links provides native
broadcast/multicast capabilities that need to be complemented
by Future Internet services, introducing and supporting a
paradigm-shift from pull of data to specific users to a push type
D. Security Evolution
The model for security in the current Internet, which
includes wireless networks (including satellite) needs to
address the challenges posed by a change of network
architecture. Satellite networks (professional and residential)
have often deployed middle-box networking devices (including
Protocol Enhancing Proxies, PEPs) that have proved
incompatible with many security solutions (including IPSec).
The security implications of middleboxes must therefore be
considered as the Internet evolves. A strong attack model must
also be assumed.
Consideration of satellite communications systems as an
integrated component of the global Internet reveals a range of
security issues. These include requirements for acceptable
security for users, protection of the network (e.g. against Denial
of Service, DoS, attacks), guarantees of acceptable availability
(in some cases supporting multiple levels of priority and
preemption), and a raft of wider security concerns applicable to
many common technologies (e.g. user privacy relating to
identity and location information, trust relationships between
users, operators and service providers), and specific issues such
as multicast key distribution.
The wide-coverage of many satellite networks, also requires
the security framework to encompass the legal mechanisms
required to deter and trace attackers, coupled with the
implications of providing lawful interception. It is important
that security is considered early in the design.
III. EVOLUTION OF SATELLITE COMMUNICATIONS
A wide range of opportunities exists for developing existing
and new markets as a bearer for Internet services:
A. A Role in Network Provision
The role of satellite communications spans a wide range of
bearer service types, geographic coverage, data rates and type
of terminals (handheld, mobile, fixed, etc). We expect this
diversity to remain as new technologies are developed and new
systems emerge, although advances in satellite terminals and
spacecraft are likely to result in significant changes in
capability, and an all-IP interface is expected to yield greater
commonality, both in the interface presented to the user
network, and applications that use the satellite network.
B. A Role in Service Provision
Satellites support a range of services, from specialised
application-oriented services (e.g. geo-location, emergency
calling, deep space relay, environmental monitoring, TV
broadcast, satellite news gathering, enhanced navigation and
localization, disaster prediction and relief, safety for critical
users, emergency communications, data transmission for the
maritime environment, aviation and trains, crisis management),
to network-centric services (e.g. internet access).
Internet Service Provider (ISP) trunking, LAN interconnect
and military/government services). We expect a tighter
coupling between the network and future services, with
services predominantly being offered over IP (IPTV, VoIP,
Peer-to-Peer, etc.) and satellite to play a more integrated role in
enabling development of new services and in guaranteeing
service continuity over large coverage areas.
C. A Role in Sustainability
Satellite communications are both environmental-friendly
and disaster-safe. No other means of communication can offer
such ecologically sensitive connectivity around the globe. In
combination with weather forecast, environmental monitoring,
and satellite navigation Satcom can offer unique services in a
location-, situation-, and context-sensitive manner. Outstanding
availability, coverage, and resilience are key factors of satellite
communications systems.
D. A Role in the Digital Society
With the emergence of network-collaboration in both
business and society, users are increasingly becoming both
consumers and producers. In parallel many activities in daily
life will increasingly become digital: health, government, and
culture.
Many digital services of tomorrow will require
simultaneous delivery of information in large quantities to all
affected citizens, resembling the service architecture currently
used for digital television. Satellites communication is key to
broadband broadcast communication.
E. A Role in Globalization
Many satellite services in the past, such as weather forecast,
environmental monitoring and satellite navigation started as
institutional services. In a world where development with
communication and access to the digital world is unlikely to
happen, Global satellite connectivity is key to developing a
digital world, e.g. a critical role in supporting the infrastructure
and aid for the least developed and developing countries.
For instance, many countries still lack of a reliable
infrastructure to support “legacy” and narrowband services,
e.g., basic voice communication. The role of satellites,
commonly jointly deployed with a short-range wireless local
loop (e.g., IEEE 802.11) is then crucial to recover the lack of a
traditional telephony network [6].
IV. CONCLUSIONS
Satellites are expected to maintain their niche markets in
satellite news gathering, rapid deployable terminals, corporate
networks, military and maritime use, and a range of other
Internet connection services.
Satellite communications will have a key role to fill the
digital divide at a service cost, reliability and quality that is
comparable to the other equivalent solutions. This is especially
so in places where the current infrastructure is not enabled for
broadband, and not likely to be for the near future. This
includes large parts of Africa, Asia, and South America, and
significant areas in the US and Europe.
To achieve these goals, and to ensure a European technical
lead, requires investment in research and development that
demands research in fundamental techniques and architectural
issues, and close collaboration between research and industry
work on applied research and trials of new systems. An
experimental-led programme will require construction of a
European testbed that can integrate satellite technology within
distributed Internet testbeds to evaluate new security, transport,
networking and terminal developments in the context of the
evolving network.
This research could be greatly enhanced by developing
common standards for systems, where possible under-pinned
by open-source implementations of software (e.g. in Linux) and
through simulation campaigns that coordinate activities by
communities that span the wide range of expertise required to
design and implement new satellite systems.
ACKNOWLEDGMENT
This work has been funded by the Satellite Network of
Excellence (JA2130). The European Satellite Communications
NoE (SatNEx II, IST-27393) is funded within the EC 6th
Research Framework Programme. The editors of this paper
gratefully acknowledge the contributions, feedback and
encouragement of the many partners in the SatNEx
JA21390FT5 activity (especially F. Davoli, S Scalise, M.
Berioli, C. Ciani, G Corazza, L. Frank, H. Cruickshank, M.
Marchese, and M. Luglio) – without whom this paper would
not been written.
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