Interplanetary Mailbox System

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.

• 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

• 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

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.

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.