[Dx4win] Telnet via Cable Modem Timeout

Thu, 18 Jul 2002 12:59:53 -0400

Generally not. The lease time is set by the DHCP server, which you, as a 
subscriber to the cable service, normally wouldn't have any control over. 
Unless you find that you are actually frequently changing IP addresses, 
this shouldn't be the cause of the problem. If your address does not change 
when renewed (which is typically the case in most systems that I've see), 
then there would be no change at all as far as connectivity is concerned. 
(In other words, merely asking for the lease to be renewed doesn't cause 
ongoing connectivity to drop.)

I'd be a little surprised to find a DHCP life of 2 hours (causing machines 
to attempt to renew every hour) because of the relatively large amount of 
network traffic that would generate. I don't want to go into too much depth 
on this list (we're already getting pretty far off topic), but one of the 
things that you do when setting up DHCP is to try to balance the available 
pool of addresses with the number of machines needing and using those 
addresses. In a cable ISP environment, usually when a cable modem gets 
hooked up and requests an address, it says connected for  a fairly lengthy 
period of time. There are different environments where network connections 
are relatively short-lived, and you have a smaller pool of addresses than 
potential users (computers_ , so when a user (computer) hasn't "checked in" 
for a while, you give the address away. However, even in that case, users 
who remain connected usually keep the same address.

As I think I mentioned once a while back, I've had some drops that I can't 
explain, and I know that my IP address did not change over the drop. (I run 
a little application that "notices" when my IP address changes so that I 
can "find" my system.)

At 12:28 PM 7/18/2002 -0400, l dietrich wrote:
>Isn't there a way to lengthen the lease interval?
>
>Lou N2TU
>----- Original Message -----
>From: "Kurt W. Zimmerman" <[email protected]>
>To: "'Pete Smith'" <[email protected]>; <[email protected]>
>Cc: <[email protected]>
>Sent: Thursday, July 18, 2002 8:17 AM
>Subject: RE: [Dx4win] Telnet via Cable Modem Timeout
>
>
> > If you read the RFP on DHCP, you will find that as long as the IP is
>active
> > that it will get renewed during its half-life of the lease.  So if you
>have
> > an expiration of 2 hours, your IP will be "renewed" every hour.
> >

73,
         David, K2DBK