Because light travels at 186,000 miles per second, it takes only a few fractions of a second to send a packet of data from one computer to another. At these distances, it can take several minutes or hours for a radio signal to reach a receiving station. An interplanetary Internet will not be able to duplicate the real-time immediacy of the Internet that you use. The satellites of the Mars Network will be tens or hundreds of millions of miles from Earth and that means that it will be hard to get up there to fix things when they go wrong. The components of these satellites would have to be much more reliable than those circling Earth.
Hackers pose the biggest threat to an interplanetary Internet.
Developers are taking every precaution to design a system that will be able to control access. The protocol selected will have to be impenetrable to hackers, something that has not been possible on Earth. The interplanetary Internet will possibly wire us to Mars within the decade and to other planets in the decades to follow. It will no longer be necessary to go into space to experience space travel. Instead, space will be brought right to your desktop.