Submit Hint Search The Forums LinksStatsPollsHeadlinesRSS
14,000 hints and counting!


Click here to return to the 'problems phoning home' hint
The following comments are owned by whoever posted them. This site is not responsible for what they say.
problems phoning home
Authored by: BjarneDM on Dec 12, '04 01:12:36PM

There're several problems with the traditional phone home scripts that'll make them inoprative in a lot of settings.

1) the smtp-server might only accept connections from the range of ip-adresses that belongs to the ISP. Most ISPs I know of does this.

2) running your own smtp-server on localhost might not work as several ISPs I know of block port 25 in order to combat spam and viruses with their own smtp-server. TDC, Tiscali, and CyberCity here in Denmark does this.

3) running your own smtp-server on localhost might not work if the ip-address that the script is sending from is registered at SORBS - http://www.dnsbl.au.sorbs.net/lookup.shtml? - and the receiving smtp-server is blocking dynamic ip-ranges. Hotmail does this eg.

4) as SFP and Domain-Keys get deployed you might run into trouble with these authentication services.

The solution?
You'll have to have your script connect to a genuine web-server on port 80 out in town that'll then take care of issuing the email alerts. I'm only aware of one product that does it that way : LapCop - http://homepage.mac.com/sweetcocoa/lapcop/

All of the other script and programs that I'm aware of are relying on your computer to generate and send an email which'll very possibly run afoul of one or more of the problems mentioned above as measures against spam, viruses and worms are deployed all over the Internet.



[ Reply to This | # ]