Internet

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The first permanent settlement on Mars will be of a size that does not necessarily require a distributed computer network. Nevertheless, there is the need for a mutual communication between people on Mars and people on Earth. The Martian settlement can, therefore, be connected to the terrestrial Internet, which in fact makes it an Interplanetary Internet.

The speed of any communication between Mars and Earth is limited to the speed of light, which results in a minimum delay (when the planets are closest to each other) of about 8 minutes for one way. This delay increases to approximately 18 minutes when the planets are in conjunction. This causes another issue as the Sun will be blocking the Line Of Sight (LOS) between the planets, communication signals will need to be re-routed via an interplanetary network,[1] increasing the time taken for signals to travel between Earth and Mars. Without special buffering the result of a mouse click appears 16 minutes (minimum), or over 36 minutes (maximum), later on the screen. Time for HTML download will add to this lag. So, at worst, a complete terrestrial web page may take over 40 minutes to display on a Mars-based computer.

Concept

The first step can be a single computer and a radio transmitter brought from Earth to Mars. On Earth there is a corresponding radio transmitter, or network of global transmitters, and a buffered interface to Earth's Internet. Internet access may only be available during certain time frames (depending on Earth/Mars phase and availability of communication satellites).

An extension is possible to widen the time windows with additional transmitters on other continents and relay stations orbiting Earth and Mars.

The buffer on Earth side should have some additional functionality:

  • Collect all files (e.g. pictures) that are related to a requested HTML page and send them together with the HTML page. This reduces the time from mouse click to complete screen display of up to 40 minutes.
  • Reduce resolution of pictures if appropriate.
  • Compress data stream.
  • Add redundancy to the signal to allow data reconstruction for lost bits. The re-transmission of TCP data packets is awfully time consuming in this case and should be avoided.
  • Another method is to construct a new method of HTML transmission (similar to the cut-down WAP service for cell phones and other mobile devices). Images and graphics may be stripped from websites leaving only HTML text.

Solutions to the Internet communications "lag"

Now I feel stupid. That's clreaed it up for me

First use cases

  • Technology information from Earth to Mars
  • Scientific results from Mars to Earth
  • Personal E-Mails in both directions

Martian Net

Eventually the number of internet servers and web homepages located in Mars will increase, thus solving many of the problems with the use of Earth based homepages.

Open Issues

  • What minimal transmitter (size, power) is required for a radio link from Earth to Mars (surface to surface)?
  • What data rate can be achieved by simple technology?
  • What time windows exist with a single transmitter on both sides?

References