23 March 1998
                                                                            07988839
                                                                          G053-L-010

Mr. Tatsuya Hagino
Workshop Chair
Keio University
Keio Research Institute at SFC
5322 Endo Fujisawa
Tokyo, Japan

Subject:	Position Paper for W3C Workshop on Mobile Access

Reference:	Registration Number Mobile WS981144

Dear Mr. Hagino:

Mobile Access to the Internet presents some interesting technical challenges. Listed 
below are a few issues that The MITRE Corporation would like to discuss at the W3C 
Mobile Web Workshop.
1. Mobile IPs.
   Mobile IP addressing for gNomadich (e.g., setting in hotel room) users appears 
   to work, but for truly mobile users mobile IP addressing poses a lot of problems. 
   Although DHCP is good news for nomadic users, it does not appear to help truly 
   mobile users.
2. Radio Frequency Assignments
   Mobile users arenft as mobile as one might think, even with GSM. Different radio 
   frequency assignments, for example, can preclude using the same equipment in the 
   US (in those areas where GSM is supported) and Europe or Japan. In the worse case, 
   you will need a different cell radio for every place you travel. Plug-in 
  gpersonality modulesh can correct some of the equipment problems by allowing a 
   person to carry the brains of a cell phone as they travel.
3. Available Bandwidth
   The available bandwidth for mobile users is too low to support many really 
   interesting Web applications. Typical bandwidth in the US is no more than 9600 
   bps (typically a lot less) and GSM, despite its other advantages, is no better.
4. Multi-path Interference/Reception
   Multi-path problems can be very difficult for TCP due to out-of-order and 
   duplicate packet behaviors, even if you ignore the high/variable latency, 
   collisions and high error rates.
5. Security:
   Existing encryption standards should be encouraged to protect information 
   transmitted over mobile communications.
6. HTML as a standard for mobile web access.
   Caution must be used in defining an extension to the HTML for mobile users. 
   Users have become accustomed to functions available on static systems and will 
   be unwilling to accepts less functionality.

                                        Sincerely,

                                        Ronald L. Angelly
                                        Site Leader
                                        Center for Integrated Intelligence Systems