Network Working Group J. Liu
Internet-Draft H. Li
Intended status: Informational Q. Wu
Expires: 26 April 2027 Y. Li
Z. Lai
Tsinghua University
23 October 2026
Security Architecture of Satellite Internet
draft-liu-satellite-internet-standardization-00
Abstract
In the 6G era of striving for global connectivity, Satellite Internet
emerges as a crucial infrastructure by providing network coverage to
remote and underserved regions. However, it confronts more intricate
security threats than terrestrial networks, encompassing dual perils
from the physical and network realms. This document reviews the
classic architectures of Satellite Internet and dissects the novel
security challenges it encounters, such as the harsh space
environment, orbit and spectrum congestion, and the resource
disparity between satellites and ground nodes. It further
scrutinizes the existing cybersecurity regulations and standards,
highlighting their inadequacies in tackling these emerging threats.
Against this backdrop, this document proposes a security architecture
standard for Satellite Internet, which encompasses physical
environment security and communication network security, with a focus
on security technologies in the electromagnetic, control, and
forwarding domains. Finally, the document outlines the future trend
of standardization efforts for Satellite Internet, underlining the
necessity of bolstering active security technologies to counteract
unknown intelligent security risks.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. A Taxonomy of Satellite Internet Architecture . . . . . . . . 5
2.1. One-to-One . . . . . . . . . . . . . . . . . . . . . . . 5
2.2. One-to-Many . . . . . . . . . . . . . . . . . . . . . . . 5
2.3. Many-to-Many . . . . . . . . . . . . . . . . . . . . . . 6
2.4. Integrated Satellite-Terrestrial Networks . . . . . . . . 6
3. Security Threats Faced by Satellite Internet . . . . . . . . 6
3.1. Physical-Space Security Threats . . . . . . . . . . . . . 6
3.1.1. Dynamic Network and Limited Control Scope . . . . . . 6
3.1.2. Orbit and Spectrum Congestion . . . . . . . . . . . . 7
3.1.3. Harsh Space Environment . . . . . . . . . . . . . . . 7
3.1.4. Asymmetric Resources Between Satellites and Terrestrial
Nodes . . . . . . . . . . . . . . . . . . . . . . . . 7
3.2. Network-Space Security Threats . . . . . . . . . . . . . 8
3.2.1. Openness: From "Walled Gardens" to Open
Interconnection . . . . . . . . . . . . . . . . . . . 8
3.2.2. Heterogeneity: Integrated Satellite-Terrestrial
Networks . . . . . . . . . . . . . . . . . . . . . . 8
3.2.3. Diversity of Services: Integrated Communication,
Navigation, Remote Sensing, and Computing . . . . . . 8
3.2.4. Intelligence: Emergence of On-Board AI . . . . . . . 9
4. Cybersecurity Regulations and Standards for Satellite
Internet . . . . . . . . . . . . . . . . . . . . . . . . 9
4.1. International Cybersecurity Regulations . . . . . . . . . 9
4.2. International Standards Bodies . . . . . . . . . . . . . 10
4.2.1. International Standardization Development . . . . . . 10
4.2.2. Development of International Standardization . . . . 11
5. Security Architecture Standards for Satellite Internet . . . 11
5.1. Design Principles . . . . . . . . . . . . . . . . . . . . 11
5.1.1. Openness . . . . . . . . . . . . . . . . . . . . . . 12
5.1.2. Scalability . . . . . . . . . . . . . . . . . . . . . 12
5.1.3. Flexibility . . . . . . . . . . . . . . . . . . . . . 12
5.1.4. Domain Separation . . . . . . . . . . . . . . . . . . 12
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5.1.5. Fault Tolerance . . . . . . . . . . . . . . . . . . . 12
5.2. Security Architecture of Satellite Internet . . . . . . . 12
5.2.1. Physical Environment Security . . . . . . . . . . . . 13
5.2.2. Electromagnetic Domain Security . . . . . . . . . . . 13
5.2.3. Control Domain Security . . . . . . . . . . . . . . . 13
5.2.4. Forwarding Domain Security . . . . . . . . . . . . . 14
6. Satellite Internet Classification . . . . . . . . . . . . . . 14
6.1. Physical Domain Security Technical Specifications . . . . 14
6.2. Control Domain Security Technical Specifications . . . . 14
6.3. Data Domain Security Technical Specifications . . . . . . 15
6.4. Service Domain Security Technical Specifications . . . . 15
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
8. Security Considerations . . . . . . . . . . . . . . . . . . . 15
9. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . 15
10. Informative References . . . . . . . . . . . . . . . . . . . 16
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction
Terrestrial wireless networks have made remarkable progress in
enhancing communication speeds and quality of service. However, they
still face significant challenges in providing coverage to remote or
underserved areas, which hinders the achievement of the 6G era's goal
of connecting everyone and everything. Satellite Internet, with its
inherent wide-area coverage capabilities, offers a direct solution to
this coverage gap. Recently, various Satellite Internet mega-
constellation projects have been established using Low Earth Orbit
(LEO) satellites, such as SpaceX's Starlink [STARLINK], OneWeb
[ONEWEB], Amazon's Kuiper [KUIPER], and Telesat [TELESAT]. These
launched constellations are extending the boundary of today's
Internet to construct an integrated space-terrestrial network.
Equipped with high-speed inter-satellite links (ISLs)
[STARLINK-LASER] and ground-satellite links (GSLs), they can
interconnect with other satellites and ground facilities for
providing planet-wide Internet service [HEO2023]. The mass-produced
spacecraft in newer constellations carry communication payloads using
Ku, Ka, and E frequency bands [STARLINK-V2].
Satellite Internet can boost the potential of a wide range of
applications:
* LEO Satellite-Assisted Computing: Provides computing and caching
services in remote areas.
* Intelligently Connected Vehicle Networks: Offers high-precision
positioning and navigation for traffic management.
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* Smart City, Agriculture, and Healthcare: Supports infrastructure
monitoring, city planning, weather forecasting, and environmental
surveillance.
* Emergency and Rescue Operations: Acts as a last-resort
communication tool in hard-to-reach regions.
* IoT and M2M Communications: Facilitates access, forwarding, and
edge computing for IIoT devices.
Hence, the value and impact of Satellite Internet on economic growth
and technological advancement are anticipated to be immense and far-
reaching.
Compared to terrestrial wireless networks, Satellite Internet faces
more severe security risks, primarily due to the following inherent
limitations:
* Complex Surrounding Environment: Satellites must operate in harsh
space conditions, where cosmic radiation may impair the electronic
devices on board.
* Asymmetric Space-Ground Capabilities: LEO satellites have limited
power, storage capacity, and computation capabilities. As a
result, many satellites cannot implement complex encryption
algorithms to protect themselves.
* Inherent Defensive Disadvantages: Satellites cannot be easily
upgraded post-launch. This makes traditional patch-based security
measures ineffective against evolving cyber threats.
* High Dynamic Changes in Space and Time: The high mobility and
limited access time of LEO satellites further complicate security
management.
These constraints leave Satellite Internet more vulnerable to cyber
threats than terrestrial networks. Therefore, a security
architecture for Satellite Internet is needed rather than reactive
fixes.
To this end, this document introduces a security architecture for
Satellite Internet from a standardization perspective. Specifically,
it begins by reviewing the evolution of Satellite Internet
architecture, highlighting different implementation paradigms in its
development. Next, it analyzes the new security threats facing
Satellite Internet, considering both physical-space and network-space
security threats. It then examines existing cybersecurity
regulations and standards for Satellite Internet, identifying gaps in
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current standards in responding to these threats. Based on this
analysis, it proposes a security architecture standard for Satellite
Internet, incorporating advanced solutions to address the identified
threats. Finally, it discusses prospective standardization efforts
on Satellite Internet needed to enhance its resilience and security.
2. A Taxonomy of Satellite Internet Architecture
The classic architectures of Satellite Internet include four types:
One-to-One, One-to-Many, Many-to-Many, and Integrated Satellite-
Terrestrial Networks. This section introduces these Satellite
Internet architectures, providing specific scenarios for analyzing
security risks.
2.1. One-to-One
The One-to-One architecture relies on Geostationary Orbit (GSO)
satellites and ground stations. GSO satellites are positioned about
35,786 kilometers above Earth to achieve wide coverage. These
satellites maintain a relatively stationary position relative to the
ground and communicate directly with ground stations via feeder
beams. Each satellite provides physical connections to users within
its coverage range through user beams. Importantly, at any given
time, one GSO satellite can only connect to one ground station.
Therefore, GSO satellites send user data to the corresponding ground
station, which then handles further processing and delivery.
2.2. One-to-Many
Compared to the "One-to-One" architecture, this architecture uses
multiple Non-Geostationary Orbit (NGSO) satellites to provide faster
broadband services than a GSO satellite. This architecture requires
more NGSO satellites for global coverage due to their limited
coverage area. Additionally, since NGSO satellites move quickly
relative to the ground, they necessitate continuous switching between
the ground station and feeder beams to maintain network service.
Specifically, user service areas are divided based on ground station
locations. NGSO satellites first route data to the corresponding
ground stations and then leverage terrestrial networks to route data
to users. Thus, the terrestrial network enables NGSO satellites to
connect to many ground stations at a given time.
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2.3. Many-to-Many
In scenarios where ground stations cannot be established outside
national territory, the network connections between satellites should
be built using ISLs to expand the satellites' service coverage.
Under this architecture, a single NGSO satellite provides services to
users within its limited coverage range. If no ground station is
available within its coverage, the satellite transmits user data to a
remote ground station via ISLs. If a ground station is available,
data is landed locally to conserve ISL resources. This architecture
enables NGSO satellites to maintain connectivity with multiple ground
stations simultaneously through a combination of ISLs and terrestrial
networks.
2.4. Integrated Satellite-Terrestrial Networks
In contrast to the "Many-to-Many" architecture, where satellite
networks and the terrestrial Internet have long developed separately
and independently, Integrated Satellite-Terrestrial Networks aim to
unify satellite and terrestrial network protocols, as shown in
Figure 1. This unification allows satellites and ground nodes to
become routing peers, facilitating agile network expansion. However,
this integration is challenging and is currently in the stage of in-
depth technical evaluation by satellite operators.
3. Security Threats Faced by Satellite Internet
Unlike Terrestrial Internet, Satellite Internet is exposed to a
complex, harsh, and uncontrolled space environment. As a result, it
faces dual security threats from both the physical and network
spaces. This section analyzes the new security risks faced by
Satellite Internet from the perspectives of the physical and network
spaces.
3.1. Physical-Space Security Threats
3.1.1. Dynamic Network and Limited Control Scope
Satellite Internet is established through the interconnection of
satellites positioned in various high, medium, and low earth orbits,
as well as terrestrial nodes. Unlike Terrestrial Internet, the high-
speed movement of satellites results in a highly dynamic network
topology, which often goes beyond the control range. This leads to
more fragile network links and nodes. Once satellites move out of
the control area, it becomes extremely challenging to effectively
detect and prevent globalized, diversified, and intelligent attacks.
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3.1.2. Orbit and Spectrum Congestion
The low earth orbits where LEO satellites operate are exceptionally
crowded. These orbits are currently occupied by over 8,300
satellites and more than 27,000 pieces of space debris. These
satellites and space fragments travel at speeds of up to 15,700 miles
per hour and have diameters of 10 centimeters or larger. Given that
the satellites are from different countries and organizations, and it
is difficult to effectively collaborate, collisions in space are
highly likely to occur.
Once a collision happens, a satellite will disintegrate into hundreds
or even thousands of pieces of space debris, further increasing the
risk of space collisions (known as the "Kessler Syndrome").
Meanwhile, as satellite communication spectrum resources are scarce,
the sharp increase in the number of satellites in orbit leads to a
dramatic rise in inter-satellite communication interference.
Therefore, Satellite Internet faces extremely serious security
threats such as physical destruction and electromagnetic
interference.
3.1.3. Harsh Space Environment
The complex and harsh space environment constantly threatens the
reliability of satellite applications in orbit. In-orbit satellites
are surrounded by cosmic rays, solar radiation, and high-energy
charged particles. Without the protection of Earth's atmospheric
barrier, these particle irradiations can cause permanent and
temporary damage to the electronic components of satellite payloads,
especially commercial semiconductor devices (such as memory bit-flip
errors). If not corrected in time, this will not only damage the
devices but also cause most orbital applications to fail, thereby
affecting the normal operation of satellites.
3.1.4. Asymmetric Resources Between Satellites and Terrestrial Nodes
The essence of security lies in the game between attack and defense,
and the essence of this game is the contest of capabilities between
the two sides. Satellites, with their limited resources and
inability to upgrade once in orbit, fall behind ground nodes in
computing, storage, and networking over their 5-10 year lifespan.
This produces an asymmetry in the attack and defense capabilities
between space and ground, making traditional "patching"-style passive
defense inadequate to effectively address the globalized,
diversified, and intelligent security risks of Satellite Internet.
As a result, a situation of "easy to attack but difficult to defend"
emerges.
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3.2. Network-Space Security Threats
3.2.1. Openness: From "Walled Gardens" to Open Interconnection
To enhance socio-economic benefits, Satellite Internet will
inevitably shift from proprietary network communication protocols to
open ones, ultimately establishing an open and interconnected
satellite-terrestrial integrated network. However, this transition
will expand its attack surface and spread the vulnerabilities and
weaknesses of open network communication protocols to satellites,
thereby posing significant security threats to Satellite Internet.
Since satellites are always in an open state, data transmission is at
risk of unauthorized access and eavesdropping, with the potential for
data to be hijacked or tampered with. Therefore, ensuring the
security of node access and the security of transmitted data is
particularly crucial for Satellite Internet.
3.2.2. Heterogeneity: Integrated Satellite-Terrestrial Networks
The integration of satellite-terrestrial heterogeneous networks has
led to a more complex network architecture and more dynamic
connections. Historically, satellites and terrestrial networks have
been isolated and heterogeneous, and are incompatible with each
other. After integration, frequent interactions across protocol
layers, network domains, and heterogeneous systems occur among nodes
such as satellites, ground stations, ground routers, and cloud
services. This results in an expanded attack surface and a
significant increase in new zero-day vulnerabilities. Moreover, due
to their independent evolution, integrated satellite-terrestrial
networks and terminals have a weak basis for mutual trust, making it
difficult to collaboratively defend against security risks.
3.2.3. Diversity of Services: Integrated Communication, Navigation,
Remote Sensing, and Computing
As satellite communication, navigation, remote sensing, and computing
capabilities continue to improve, Satellite Internet will serve as a
satellite-terrestrial integrated infrastructure, potentially
providing diverse information services such as communication,
navigation, and remote sensing to users in space-based, airborne,
land-based, and maritime platforms. This leads to an expansion of
Satellite Internet security from traditional cybersecurity to an
integrated security of communication, navigation, remote sensing,
computing, and data, further expanding the attack surface and making
the security situation more severe.
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3.2.4. Intelligence: Emergence of On-Board AI
As the number of satellites increases and hardware capabilities
improve, the volume of on-board data is growing much faster than the
data transmission capabilities between satellites and ground
infrastructure. To address this, satellite edge computing has been
proposed. It leverages the computing platforms of satellite payloads
to process on-board data, thereby reducing transmission demands or
running tasks directly on the satellite. With AI on-board, satellite
payloads now serve as new computing power leasing platforms. This
shift extends the attack surface to computing power, making it harder
to monitor and detect unauthorized users who launch on-board side-
channel attacks by using on-board computing resources in uncontrolled
areas.
4. Cybersecurity Regulations and Standards for Satellite Internet
4.1. International Cybersecurity Regulations
From an international perspective, the United States, as a
representative country, has been committed to accelerating the layout
of satellite network cybersecurity strategy in order to grasp the
initiative in space security.
In September 2020, the Fifth Space Policy Directive explicitly
required the integration of cybersecurity into the entire life cycle
of satellite network development to enhance the cybersecurity of
space systems.
In April 2022, the U.S. Congress passed the Satellite Cybersecurity
Act, which required the formulation of cybersecurity recommendations
for U.S. satellite operators and the provision of resources to them
to address the cybersecurity threats of commercial satellite systems.
In March 2023, the U.S. National Science and Technology Council
released the National Low Earth Orbit Research and Development
Strategy, proposing the establishment of a low Earth orbit national
laboratory by NASA to strengthen several cutting-edge research areas,
including satellite cybersecurity.
In April 2023, the U.S. Cyberspace Solarium Commission recommended
that the Department of Homeland Security designate space systems as
critical infrastructure to reduce satellite cybersecurity
vulnerabilities.
In May 2023, the U.S. Department of State, in its Framework for
Space Diplomacy Strategy document, proposed the continuous
strengthening of space cybersecurity and information and
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communication technologies represented by Satellite Internet, and the
enhancement of the security and resilience of critical infrastructure
related to space.
In November 2023, the U.S. Department of Defense announced that it
was developing its first Commercial Space Integration Strategy to
promote the integration of commercial technologies and ensure viable
commercial space solutions during competition, crisis, and conflict.
4.2. International Standards Bodies
4.2.1. International Standardization Development
NIST: The US National Institute of Standards and Technology (NIST)
has released four satellite cybersecurity risk management guidance
frameworks to help commercial satellite operators identify
cybersecurity risks in space, ground, user segments, and hybrid
satellite networks. Commercial satellite-related entities should
refer to a set of standards to incorporate cybersecurity risk
management into their overall risk management plans.
CCSDS: The Consultative Committee for Space Data Systems (CCSDS)
aims to develop communication protocols and data processing
standards for space telemetry and data transmission systems. It
categorizes security threats into active (e.g., jamming) and
passive (e.g., eavesdropping). In 2003, it formed the Security
Working Group (SEC-WG) to provide security recommendations and
solutions, develop security mechanisms and policies, and guide
other working groups on security considerations. This group has
produced standards and guidelines on space security architecture,
threat documentation, security protocols, key management, and
encryption/authentication algorithms.
ITU-R: The ITU-R's WP4B working group focuses on satellite network
standards, covering FSS, BSS, and MSS systems' air interfaces,
performance, and applications. In 2010, it initiated research on
the integration of satellites with IMT-Advanced, completing a
report on visions and requirements in 2012. The ITU-R M.2083
recommendation highlighted the need for anytime, anywhere service
access, leading to the development of the ITU-R M.NGAT_SAT
standard for 5G satellite networks, completed in March 2018, which
defined key aspects including applications, network structure, and
technologies.
ITU-T: ITU-T SG13 has taken the lead in proposing the technical
concept and standard system of fixed, mobile, and satellite
convergence (FMSC), which is the world's first series of
international standards for integrated space-ground networks. At
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the ITU-T SG13 plenary meeting, the completion of three
standardization projects further improved the FMSC standard system
and evolved the topic group into "IMT-2030 Network: Fixed, Mobile
and Satellite Convergence" in the new research period.
3GPP/ETSI: 3GPP has been working to adapt 5G NR, NB-IoT, and LTE-M
to meet satellite communication needs. Releases R15 to R18
progressively address satellite-5G integration, from basic
requirements to detailed solutions for network architecture,
protocol stacks, and functional requirements for different network
components.
4.2.2. Development of International Standardization
CCSA TC12: In 2020, CCSA established TC12 to focus on space
communication standards and research. Over three years, TC12 has
worked on standards for VSAT, mobile satellite protocols, airborne
communications, IoT, integrated 5G networks, GEO, and BeiDou short
messaging. It has also explored topics like ATG, DVB-S2X, 5G
enhancements, bearer networks, and applications. As Satellite
Internet and smartphone-to-satellite links gain attention, various
channels are actively involved in satellite communication
standard-setting and research.
TC425: TC425 is guided by the Standardization Administration of
China. It focuses on national standards for space product design,
production, integration, testing, satellite applications, project
management, materials, processes, data and information
transmission. TC425 develops China's standard system and roadmap
for space data and information transmission, including Satellite
Internet, and drafts relevant white papers. It has six subgroups
covering space environment, electronics, data transmission,
assembly and testing, debris, and materials.
The Satellite Internet market is growing, with increasing focus on
cybersecurity. However, progress in related legislation and
standardization is slow. Satellite Internet, as critical
infrastructure, has broader coverage and greater cybersecurity
impacts compared to terrestrial infrastructure. Some existing
standards are outdated and unsuitable for new satellite technologies
and cybersecurity needs. Cybersecurity and satellite industry
professionals need to collaborate to build a comprehensive Satellite
Internet security system.
5. Security Architecture Standards for Satellite Internet
5.1. Design Principles
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5.1.1. Openness
The security architecture should be easily accessible, and its
licensing should be reasonable and non-discriminatory. The use of
proprietary technologies is not excluded, but the open standards and
protocols, open security tools and frameworks, and general security
technologies (e.g., encryption algorithms) that are used must be
provided in a non-restrictive manner.
5.1.2. Scalability
The architecture should be scalable and evolvable to allow for the
incorporation of new security measures, such as those needed to
address new threats or mission requirements. It is desirable to
permit remote upgrades of deployed systems.
5.1.3. Flexibility
The architecture should allow for the development of different
security systems that will be suitable for most satellite missions.
The use of the security architecture should permit mission-specific
configurations to ensure compatibility with each other.
5.1.4. Domain Separation
Security is achieved through domain separation mechanisms. The use
of multi-domain security enhances the overall system security, with
all domains forming an integrated whole that does not expose the
system to the risk of compromise.
5.1.5. Fault Tolerance
Security mechanisms should be able to recover from failures.
Recovery mechanisms should not expose vulnerabilities in the system.
However, special cases may indicate the need to degrade security
mechanisms, such as recovering by entering a predefined safe state to
perform tasks. These cases should be identified and evaluated as
part of the mission recovery design.
5.2. Security Architecture of Satellite Internet
The security architecture of the Satellite Internet is shown in
Figure 1 and is divided into physical environment security,
communication network security, and application security. Among
them, physical environment security is divided into space segment and
ground segment physical environment security, and communication
network security includes electromagnetic domain, control domain, and
forwarding domain security.
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+---------------------------------------------------------------+
| Satellite Internet Security Architecture |
+-----------------------+---------------------------------------+
| Physical Environment | Communication Network Security |
| Security | |
| +-------------------+ | +-----------------------------------+ |
| | Space Segment | | | Electromagnetic Domain Security | |
| +-------------------+ | +-----------------------------------+ |
| | Ground Segment | | | Control Domain Security | |
| +-------------------+ | +-----------------------------------+ |
| | | Forwarding Domain Security | |
| | +-----------------------------------+ |
+-----------------------+---------------------------------------+
Figure 1: Security Architecture of Satellite Internet
5.2.1. Physical Environment Security
The physical environment in which satellites operate is complex and
harsh, with frequent cross-border movements and control levels
affected by high spatiotemporal dynamics. Therefore, it faces more
severe physical domain attacks than terrestrial networks. The
physical environment security of Satellite Internet ensures the
physical security of space segment satellites and ground segment
systems, including ground information systems and radio frequency
antennas.
5.2.2. Electromagnetic Domain Security
The open wireless channels, long-distance transmission, wide
coverage, and complex operating environment of Satellite Internet
make it more susceptible to physical domain attacks than terrestrial
wireless networks, such as interference, eavesdropping, and
deception. These attacks threaten the confidentiality, availability,
and integrity of Satellite Internet. The electromagnetic domain
security of Satellite Internet mainly addresses anti-jamming,
eavesdropping prevention, and deception avoidance.
5.2.3. Control Domain Security
The control domain of Satellite Internet is responsible for core
control functions such as satellite link access, authentication and
authorization, access control, and routing transmission. It is the
"brain" of Satellite Internet. Therefore, the control domain is a
key target for Satellite Internet attacks. The control domain
security of Satellite Internet mainly includes identity
authentication and key management, access control, link control,
routing control, and transmission control.
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5.2.4. Forwarding Domain Security
The forwarding domain of Satellite Internet is responsible for
routing and forwarding network data and needs to ensure the
confidentiality, integrity, availability, and traceability of data
forwarding. The security and trustworthiness of the forwarding
domain are crucial to its service quality. The forwarding domain
includes source address verification, data forwarding security,
abnormal traffic detection and tracing, data confidentiality
protection, and data integrity protection.
6. Satellite Internet Classification
As the Satellite Internet evolves to an integrated space-ground
Internet, new global, diverse, and intelligent security risks will
continue to emerge. Traditional "patching" passive defense will be
insufficient. Thus, it is necessary to shift to active security and
trustworthy technologies, enhancing the Satellite Internet's ability
to immunize, coexist with, and "live with" unknown intelligent
security risks.
6.1. Physical Domain Security Technical Specifications
The Satellite Internet is a cyber-physical network operating in a
complex environment, where cyber and physical security are
interwoven. Future research will focus on enhancing cybersecurity in
the uncontrolled, highly dynamic space environment. This includes
collaborative design with satellite autonomous driving, radiation
resistance, and electromagnetic interference mitigation. Cross-
disciplinary innovation between network and aerospace fields will be
key to achieving integrated security protection.
6.2. Control Domain Security Technical Specifications
Exposed satellite nodes, open channels, and dynamic network topology
make the Satellite Internet's core functions more vulnerable.
Frequent interoperability across different protocols and systems
further expands the attack surface. Future research will focus on
active suppression of multidimensional security risks, with
breakthroughs in collaborative threat detection and protection
technologies to evolve from single-point to multi-point collaborative
defense.
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6.3. Data Domain Security Technical Specifications
Limited satellite resources and the difficulty of timely updates
constrain security defense. Traditional passive defense is
insufficient against advanced attacks. Future research will focus on
networked collaborative active defense to amplify defense
capabilities, increase attack costs, and disrupt attack chains,
shifting from a passive to an active defense posture.
6.4. Service Domain Security Technical Specifications
As the number of satellites increases and their capabilities enhance,
the Satellite Internet will support diverse and integrated services,
including communication, navigation, remote sensing, and computing.
Future research will focus on integrated security technologies to
ensure the interoperability and security of these services,
safeguarding the Satellite Internet's comprehensive service
capabilities.
7. IANA Considerations
This document has no IANA actions.
8. Security Considerations
This document discusses security threats and a proposed security
architecture for Satellite Internet. It does not define a new
protocol or specify an implementable security mechanism. The
proposed architecture is intended to support further analysis and
standardization; it does not, by itself, guarantee the security of a
Satellite Internet system. Implementations and deployments based on
this architecture need to assess the applicable threat model,
operational environment, trust boundaries, and security requirements.
Specific security mechanisms should be selected and evaluated
according to the system's intended use and identified risks.
9. Conclusion
This document proposes a security architecture for Satellite Internet
from a standardization perspective. The architecture provides
comprehensive coverage of security technologies across the physical
environment domain, electromagnetic domain, control domain, and
forwarding domain through multi-layered protection of the physical
environment and communication network security. It not only
addresses the unique challenges of Satellite Internet, such as the
complex space environment, orbit and spectrum congestion, and
asymmetric resources between satellites and ground nodes, but also
offers targeted solutions to enhance the active security and
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trustworthiness of Satellite Internet. In addition, this document
explores the direction of future standardization efforts, emphasizing
the importance of improving the immune capability, coexistence
capability, and "living with" capability of Satellite Internet in the
face of unknown intelligent security risks. Enhancing the active
security and trustworthiness of Satellite Internet is crucial for its
development; accelerating research and development in Satellite
Internet security technologies will lay the foundation for an open,
shared, intelligent, and efficient global solution.
10. Informative References
[HEO2023] Heo, J., Sung, S., and H. Lee, "MIMO Satellite
Communication Systems: A Survey from the PHY Layer
Perspective", IEEE Communications Surveys & Tutorials vol.
25, no. 3, pp. 1543-1570, 2023.
[KUIPER] GeekWire, "Amazon Project Kuiper Broadband Satellite",
2019, .
[ONEWEB] OneWeb, "OneWeb", .
[STARLINK] SpaceX, "Starlink", .
[STARLINK-LASER]
WCCFtech, "SpaceX Successfully Tests Inter-Satellite
Starlink Connectivity via Lasers", .
[STARLINK-V2]
Gunter's Space Page, "Starlink V2.0 SS",
.
[TELESAT] Telesat, "Telesat", .
Acknowledgements
The authors would like to thank all contributors who provided
valuable feedback and input to this document.
Authors' Addresses
Jun Liu
Tsinghua University
Email: juneliu@tsinghua.edu.cn
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Hewu Li
Tsinghua University
Email: lihewu@cernet.edu.cn
Qian Wu
Tsinghua University
Email: wuqian@cernet.edu.cn
Yuanjie Li
Tsinghua University
Email: yuanjiel@tsinghua.edu.cn
Zeqi Lai
Tsinghua University
Email: zeqilai@tsinghua.edu.cn
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