Re: AS/400 IP COMMUNICATION WAIT TIME -- MIDRANGE-L

Bob/Jim:
Why then when I disconnect my laptop which is connected to my AS400 via IP,
and move to a different office in my building and plug back into the network
that I still have the same session connect.  It never misses a beat?
CJG

Carl Galgano
EDI Consulting Services, Inc.
540 Powder Springs Street
Suite C19
Marietta, GA  30064
770-422-2995
mailto: cgalgano@ediconsulting.com
http://www.ediconsulting.com
EDI, Communications and AS400 Technical Consulting

-----Original Message-----
From: Bob Crothers <bob@cstoneindy.com>
To: MIDRANGE-L@midrange.com <MIDRANGE-L@midrange.com>
Date: Friday, January 07, 2000 8:41 AM
Subject: RE: AS/400 IP COMMUNICATION WAIT TIME


>Jim,
>
>You've got it mostly right.  Except the part about TCP being "Connection
>Based".  It does not have to be that way.  Look at HTTP.  The connection is
>not maintained for the duration of the session.  Only while data is being
>exchanged.  Other protocols/applications are different.  Telnet is
>connection based.  FTP is actually both.  The control part of the
>conversation is connection based, but data is exchanged over a
>connectionless conversation.  And custom applications can be how ever you
>want them.
>
>The main difference between TCP & UDP is that when you send data via TCP,
it
>is guaranteed to not only arrive at the destination (or cause an error) but
>also in the same order you send it.
>
>When you send with UDP, not only is the data NOT guaranteed to arrive at
the
>destination, but the data MIGHT be out of order.  As a result, UDP tends to
>be used for "trivial" things (like ping) or broadcast where each byte of
>data is not that important (streaming sound/video).
>
>Bob
>
>-----Original Message-----
>From: owner-midrange-l@midrange.com
[mailto:owner-midrange-l@midrange.com]On
>Behalf Of Jim Langston
>Sent: Thursday, January 06, 2000 6:13 PM
>To: MIDRANGE-L@midrange.com
>Subject: Re: AS/400 IP COMMUNICATION WAIT TIME
>
>Short answer: it is not possible to disconnect without the clients
>"knowing".
>
>Long answer:
>TCP is a connection scheme.  When using TCP/IP the connection
>remains open.  Once the communication between the server and
>the client is closed, the TCP/IP connection is closed.  UDP, on
>the other hand, is a broadcast scheme.  There is no permanent
>connection.
>
>Since the majority of IP communication is TCP based (including
>client access and the like) if you disconnect the cable from either
>the server or the client the channel is closed, and the program
>errors out, either graceful with a window saying the session has
>been terminated, or ungraceful for programs not looking for this.
>
>Once you disconnected and reconnected, the connections would
>have to be re-established.
>
>Regards,
>
>Jim Langston
>
>oludare wrote:
>
>> Hi Guys, I need to know.  Is it possible to disconnect the RJ45 that
>> connects all CLIENTS (PCs) to the AS/400 box, communicating over IP,
>> and reconnect back without any CLIENT knowing that communication was
>> interrupted.  What happen to all active interactive jobs (programs)
>> from the PCs and Session Manager? Thanks for you help. Oludare
>
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