[Cryptography] Fast handling of IP Address changes for HTTPS

[Dennis E. Hamilton]

-----Original Message-----
From: cryptography [mailto:cryptography-bounces+dennis.hamilton=acm.org at metzdowd.com] On Behalf Of Bill Stewart
Sent: Saturday, December 30, 2017 00:27
To: cryptography at metzdowd.com
Subject: Re: [Cryptography] Fast handling of IP Address changes for HTTPS

On 12/28/2017 1:35 PM, Paul F Fraser wrote:
> Hi,
> 
> Running a webserver on a home system suffers from the problem of IP 
> Address changes after modem reboot.
> 
> In Australia with the National Broadband Network (NBN) I am also 
> experiencing IP Address changes without the modem disconnecting. It may 
> not be general, but in my case it seems that a fixed IP Address is not 
> available.
Can you set up IPv6 tunnels to your ISP, and are their addresses stable 
even if the IPv4 address isn't?

[orcmid]
  I think the problem is accessing his web server from the external (WAN) Internet.  Access from other local (LAN) machines does not require the gateway functions of the modem (ignoring DHCP accommodation).

Depending on the technology between the household and the ISP, it is not unusual for the residential modem's IP "lease" to renew spontaneously in some periodic manner and/or whenever the modem is rebooted.  If there is an IPv6 lease, it might also be regenerated.  

Some ISPs provide fixed IP addresses to residential modems, sometimes for an additional fee.

There have also been services that provide a pseudo-DNS that will route into a residential modem, with a local application running on the local server that keeps the pseudo-DNS updated with the modem's WAN IP address.  I know that was used with the Hewlett-Packard Windows Home Server implementation.  

These days, I think the answer is to find an inexpensive/free in-the-cloud location for a web site.  GitHub comes to mind, for one, so long as you are willing for it to be public.  For simple file-sharing, there are many free services with privacy controls and off-site backup might come along with it.