About
|
Delivery of large packages of information across interplanetary distances
is one crucial need for support of a human mission to Mars, or even of
advanced robotic missions to Mars. As part of our
PlanetNet project, we
are looking at the protocols that can achieve delivery of these packages.
The primary problem is delivery of information in a reliable robust fashion,
across links which, due to the limitations of light-speed communication,
make it impossible to use conventional mail or file transfer protocols
based on the TCP/IP standard. However, at the same time, we wish to ensure
that conventional COTS software can be used for transmitting, receiving,
and providing local distribution and storage of the information. This
includes the use of commercial grade mail server systems providing the
full messaging capability expected of professional software.
|
Requirements
|
We have identified the following requirements:
- Use of COTS mail and file transfer servers for user access to
system
- Use of COTS mail and file transfer clients for access to servers
- Full interoperability with Internet protocols
- Capable of handling interplanetary communication links with high
error rates and delays
- Capable of providing dynamically changing quality of service
capabilities and variable multiplexing volume
- Capable of providing for efficient multiple delivery of different sites
in the Solar System
|
Benefits
|
The benefits of such a system are as follows:
- Provides base capabilites for Mission Control data transmission to
and from Human explorers located in the inner Solar System, including
on the Moon and Mars.
- Provides base capabilites for reliable delivery of complex
information to and from robotic probes in the Solar system, including
on planetary surfaces
- Provides capabilites for Earth use, including disaster response and
relief operations via large delay networking and messaging technologies.
- Provides for empowerment of remote communities via access to,
and ability to produce, large scale information products
|
Technology
|
The technology is based on simply developing advanced Mail Transfer
Agents (MTAs) that can operate inside conventional COTS mail server systems,
and provide the protocols and command and control infrastructure for
file delivery in environments in which the Simple Mail Transfer Protocol
(SMTP) does not function efficiently. The MTAs simply provide links
between commercial-grade server systems, leaving user interface to
conventional mail client software such as Netscape, Outlook,
Eudora, and so on.
The concept is based on our approach to interplanetary networking, in
which we try to use as much COTS capability as possible. The idea is
to avoid the development of new protocols as much as possible, and also
to not use one approach to solve all problems. It is essential that
we remain flexible to new needs and new solutions to the issues and
problems in interplanetary and other long-delay networking.
|
Status
|
The first demonstration MTA has been produced and has been used for
transmitting complex mail messages between servers with many different
file attachments, in a wide range of formats.
The next stage is to test the system using the Mars Networking
Testbed presently in development at PolyLAB.
After testing in the development, at Mars delays and link qualities,
the MTA will be improved to reach the robustness needed for an
operational system.
|
|