Interplanetary Internet
Encyclopedia
The Interplanetary Internet (IPN) is a conceived computer network
Computer network
A computer network, often simply referred to as a network, is a collection of hardware components and computers interconnected by communication channels that allow sharing of resources and information....
in space, consisting of a set of network nodes
Node (networking)
In communication networks, a node is a connection point, either a redistribution point or a communication endpoint . The definition of a node depends on the network and protocol layer referred to...
which can communicate with each other. Communication would be greatly delayed by the great interplanetary distances, so the IPN needs a new set of protocols
Communications protocol
A communications protocol is a system of digital message formats and rules for exchanging those messages in or between computing systems and in telecommunications...
and technology
Technology
Technology is the making, usage, and knowledge of tools, machines, techniques, crafts, systems or methods of organization in order to solve a problem or perform a specific function. It can also refer to the collection of such tools, machinery, and procedures. The word technology comes ;...
that are tolerant to large delays and errors. While the Internet as we know it tends to be a busy network of networks with high traffic, negligible delay and errors, and a wired backbone, the Interplanetary Internet is a store-and-forward network of internets that is often disconnected, has a wireless backbone fraught with error-prone links and delays ranging to tens of minutes, even hours, even when there is a connection.
Development
Space communication technology has steadily evolved from expensive, one-of-a-kind point-to-point architectures, to the re-use of technology on successive missions, to the development of standard protocols agreed upon by space agencies of many countries. This last phase has gone on since 1982 through the efforts of the Consultative Committee for Space Data SystemsConsultative Committee for Space Data Systems
The Consultative Committee for Space Data Systems was formed in 1982 by the major space agencies of the world to provide a forum for discussion of common problems in the development and operation of space data systems...
(CCSDS), a body composed of the major space agencies of the world. It has 11 member agencies, 22 observer agencies, and over 100 industrial associates.
The evolution of space data system standards has gone on in parallel with the evolution of the Internet, with conceptual cross-pollination where fruitful, but largely as a separate evolution. Since the late 1990s, familiar Internet protocols and CCSDS space link protocols have integrated and converged in several ways, for example, the successful FTP file transfer to Earth-orbiting STRV-1b on January 2, 1996, which ran FTP over the CCSDS IPv4-like Space Communications Protocol Specifications
Space Communications Protocol Specifications
The Space Communications Protocol Specifications are a set of extensions to existing protocols and new protocols developed by the Consultative Committee for Space Data Systems to improve performance of Internet protocols in space environments...
(SCPS) protocols. Internet Protocol use without CCSDS has taken place on spacecraft, e.g., demonstrations on the UoSAT-12 satellite
UoSAT-12 satellite
UoSAT-12, the twelfth satellite in the University of Surrey series, was designed and built by Surrey Satellite Technology Ltd . It was launched to low Earth orbit on 21 April 1999....
, and operationally on the Disaster Monitoring Constellation
Disaster Monitoring Constellation
The Disaster Monitoring Constellation consists of a number of remote sensing satellites constructed by Surrey Satellite Technology Ltd and operated for the Algerian, Nigerian, Turkish, British and Chinese governments by DMC International Imaging...
. Having reached the era where networking and IP on board spacecraft have been shown to be feasible and reliable, a forward-looking study of the bigger picture was the next phase.
Jet Propulsion Laboratory
Jet Propulsion Laboratory is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. The facility is headquartered in the city of Pasadena on the border of La Cañada Flintridge and Pasadena...
(JPL) was started by a team of scientists at JPL led by Vinton Cerf and Adrian Hooke. Cerf is one of the pioneers of the Internet on Earth, and currently holds the position of distinguished visiting scientist at JPL. Hooke is one of the directors of the CCSDS.
While IP-like SCPS protocols are feasible for short hops, such as ground station to orbiter, rover
Rover (space exploration)
A rover is a space exploration vehicle designed to move across the surface of a planet or other astronomical body. Some rovers have been designed to transport members of a human spaceflight crew; others have been partially or fully autonomous robots...
-to-lander, lander-to-orbiter, probe-to-flyby, and so on, delay-tolerant networking is needed to get information from one region of the solar system
Solar System
The Solar System consists of the Sun and the astronomical objects gravitationally bound in orbit around it, all of which formed from the collapse of a giant molecular cloud approximately 4.6 billion years ago. The vast majority of the system's mass is in the Sun...
to another. It becomes apparent that the concept of a "region" is a natural architectural factoring of the InterPlanetary Internet.
A "region" is an area where the characteristics of communication are the same. Region characteristics include communications, security, the maintenance of resources, perhaps ownership, and other factors. The Interplanetary Internet is a "network of regional internets."
What is needed then, is a standard way to achieve end-to-end communication through multiple regions in a disconnected, variable-delay environment using a generalized suite of protocols. Examples of regions might include the terrestrial Internet as a region, a region on the surface of the moon or Mars, or a ground-to-orbit region.
The recognition of this requirement led to the concept of a "bundle" as a high-level way to address the generalized Store-and-Forward problem. Bundles are an area of new protocol development in the upper layers of the OSI model
OSI model
The Open Systems Interconnection model is a product of the Open Systems Interconnection effort at the International Organization for Standardization. It is a prescription of characterizing and standardizing the functions of a communications system in terms of abstraction layers. Similar...
, above the Transport Layer with the goal of addressing the issue of bundling store-and-forward information so that it can reliably traverse radically dissimilar environments constituting a "network of regional internets."
Bundle Service Layering, implemented as the Bundling protocol suite for delay-tolerant networking, will provide general purpose delay-tolerant protocol services in support of a range of applications: custody transfer, segmentation and reassembly, end-to-end reliability, end-to-end security, and end-to-end routing among them. The Bundle Protocol was first tested in space on the UK-DMC satellite
UK-DMC
The UK-DMC satellite is one of a number of satellites in the Disaster Monitoring Constellation . It was built by Surrey Satellite Technology, who operate it via DMC International Imaging on behalf of the UK Space Agency...
in 2008.
Coherent file distribution protocol
Coherent File Distribution Protocol is an IETF-documented experimental protocol intended for high-speed one-to-many file transfers. Class 1 is assured delivery, class 2 is blind unassured delivery.See ....
, which unfortunately has the same acronym and is an IETF-documented experimental protocol for rapidly deploying files to multiple targets in a highly-networked environment.
In addition to reliably copying a file from one entity (i. e., a spacecraft or ground station) to another entity, the CCSDS CFDP has the capability to reliably transmit arbitrary small messages defined by the user, in the metadata
Metadata
The term metadata is an ambiguous term which is used for two fundamentally different concepts . Although the expression "data about data" is often used, it does not apply to both in the same way. Structural metadata, the design and specification of data structures, cannot be about data, because at...
accompanying the file, and to reliably transmit commands relating to file system management that are to be executed automatically on the remote end-point entity (i. e., a spacecraft) upon successful reception of a file.
Implementation
The dormant InterPlanetary Internet Special Interest Group of the Internet SocietyInternet Society
The Internet Society or ISOC is an international, nonprofit organization founded during 1992 to provide direction in Internet related standards, education, and policy...
has worked on defining protocols and standards that would make the IPN possible. The Delay-Tolerant Networking Research Group (DTNRG) is the primary group researching Delay-tolerant networking. Additional research efforts focus on various uses of the new technology.
, NASA has canceled plans to launch the Mars Telecommunications Orbiter
Mars Telecommunications Orbiter
The Mars Telecommunications Orbiter was a cancelled Mars mission that was originally intended to launch in 2009 and would have established an Interplanetary Internet between Earth and Mars...
in September 2009; it had the goal of supporting future missions to Mars and would have functioned as a possible first definitive Internet hub around another planetary body. It would use optical communications using laser
Laser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...
beams for their lower ping
Ping
Ping is a computer network administration utility used to test the reachability of a host on an Internet Protocol network and to measure the round-trip time for messages sent from the originating host to a destination computer...
rates than radiowaves. "Lasercom sends information using beams of light and optical elements, such as telescopes and optical amplifiers, rather than RF signals, amplifiers, and antennas"
NASA JPL continued to test the DTN protocol with their Deep Impact Networking (DINET) experiment on board the Deep Impact/EPOXI
EPOXI
EPOXI is a NASA unmanned space mission led by the University of Maryland using the existing Deep Impact vehicle to begin a new series of observations. It first investigated extrasolar planets and, on November 4, 2010, it performed a close approach to the comet 103P/Hartley...
spacecraft in October, 2008.
In May 2009, DTN was deployed to a payload on board the ISS
ISS
The ISS is the International Space Station.ISS may also refer to:* I See Stars, an American electronic rock band* ISS A/S, a Danish service company* Idea Star Singer, a Malayalam music reality show by Asianet TV...
. NASA and BioServe Space Technologies, a research group at the University of Colorado, have been continuously testing DTN on two Commercial Generic Bioprocessing Apparatus (CGBA) payloads. CGBA-4 and CGBA-5 serve as computational and communications platforms which are remotely controlled from BioServe's Payload Operations Control Center (POCC) in Boulder, CO. These initial experiments provide insight into future missions where DTN will enable the extension of networks into deep space to explore other planets and solar system points of interest. Seen as necessary for space exploration, DTN enables timeliness of data return from operating assets which results in reduced risk and cost, increased crew safety, and improved operational awareness and science return for NASA and additional space agencies.
DTN has several major arenas of application, in addition to the Interplanetary Internet, which include sensor networks, military and tactical communications, disaster recovery, hostile environments, mobile devices and remote outposts. As an example of a remote outpost, imagine an isolated Arctic village, or a faraway island, with electricity, one or more computers, but no communication connectivity. With the addition of a simple wireless hotspot in the village, plus DTN-enabled devices on, say, dog sleds or fishing boats, a resident would be able to check their e-mail or click on a Wikipedia article, and have their requests forwarded to the nearest networked location on the sled's or boat's next visit, and get the replies on its return.
In fiction
In the Star Trek universe, members of the United Federation of Planets often send messages, in a generally instantaneous manner. An example would be a character (e.g. James Kirk or Jean-Luc Picard) speaking with another Federation officer tens, hundreds or even thousands of light years away. Whilst this is evidently a fictional scenario, it depicts in theory what an interplanetary Internet could look like, or at the least how communication between networks and hosts could occur over vast distances.See also
- InterPlaNetInterPlaNetInterPlaNet , not to be confused with InterPlanetary Network, is a computer networking protocol designed to operate at interplanetary distances, where traditional protocols such as the Internet Protocol break down...
- Delay-tolerant networking
- Intergalactic Computer Network
- Nanoscale networkNanoscale networkA nanonetwork or nanoscale network is a set of interconnected nanomachines, i.e., devices in the order of a few hundred nanometers or a few micrometers at most, which are able to perform only very simple tasks such as computing, data storing, sensing and actuation...
- Wizzy Digital CourierWizzy Digital CourierWizzy Digital Courier is a project to distribute useful data to places with no Internet connection. Primarily for e-mail, it also carries web content . From an early description of the project 1:...
External links
- The Consultative Committee for Space Data Systems (CCSDS)
- The InterPlaNetary Internet Project IPN Special Interest Group
- The Delay-Tolerant Networking Research Group (DTNRG)
- NASA video: DINET-DTN w/Vint Cerf (requires Flash)