Subject: Re: TN3270E Digest - 1 Dec 1997 to 3 Dec 1997

From: John Hind <[email-masked]>
Date: Tue, 9 Dec 1997 14:47:31 -0500

In response to Michael's response "Another trip on the merry go 'round...."
but without trying to quote the message chain which has become a bit garbled by
several passes though various mail gateways:

 I think we are saying the same thing, if a server speaks both inside and
outside an intranet then it can avoid topology knowledge if there are unique
inside and outside way of accessing it be  that by multiple IP addresses or
multiple ports.  I probably should have made the multiple  IP address point
clear in the various "port" discussions,  what I meant to say is address.port
so there is no difference in my mind in a single server instance which is known
by one host address with two port addresses (e.g. ahost.xyx.com:23 and
ahost.xyz.com:8023 )  and another single instance known by two host addresses
with the same port (e.g.  intrahost.com:23 and externhost.xyz.com:23 ).

 With respect to LUs vers Applications, I was simply pointing out that that The
TN server can only control what LUs are used NOT what application they may or
may not talk to and that it is often true that the host application changes
over the life of the session.

 As to why I think there will always be a need for an access control manager on
the host that needs the end-user identity -- because many of the existing host
applications already restrict user access/action on  and object by object basis
and I see no reason for this to shrink in the future (in fact the opposite is
true). IP addresses and ports are just not the stuf of application access
control, in fact with today's network dynamics they do not even represent fixed
physical boxes.

 On the "smartcard" example, If you can install a smartcard + a crypto
framework + a TN client that uses the cryto-framework to access the card then
surely you can add a "smartcard connect" ICON with the  secure port number at
the same time without changing more than  1/2% of this install. When one
considers you need at least a  checkmark to switch over (given you want
security) then the  change is close to nill.

  My comment on the human factors of the certificate messages was meant to
indicate that a non-technical user has no idea what the yes/no options mean to
him. We should either  try not to ask or put the question in more general terms
(e.g. "answering yes means that  someone might be intercepting  this session
and recording passwords, credit card , or other sensitive  information.  ...."
rather than "certificate apparently signed by MICR0SOFT, Proceed ?")