A couple years back, someone did a study of the probe traffic and estimated the average time to live for an new / unpatched / unprotected Windows system on the Internet was 7 minutes.
FYI, most NAT systems allow incoming traffic only for the same IP+port source+destination pair as the outgoing UDP traffic. So, you're only exposed if the guy you connected to wants to (and could even do) nasty stuff through that return channel. I.e., it gives UDP similar abilities as TCP in terms of dynamic rules.
Well, I'd normally chalk it up to browser bloat, etc., but further testing has been interesting.
telnet://time-a.timefreq.bldrdoc.gov:13 (NIST in Boulder, CO) versus telnet://tock.usno.navy.mil:13 (USNO in Maryland)
Yields different times, consistent with what's being discussed here. Tock seems to be in sync with the web page, but NIST is ahead by 1-2 seconds. Everything I can find says they're supposed to be in sync, with no allowance for leap seconds that isn't in the other.
My next best guess is that USNO is being overrun by traffic, or is seeing errors on their links, either of which would cause retransmissions for TCP traffic and shift the time display as TCP re-sends. This is consistent with the behavior seen when telnetting to USNO vs. NIST above.
NTP should be more resilient because it's UDP-based (i.e., won't retransmit a stale packet) and has mechanisms for detecting network latency. Clearly, TCP-based connections to USNO are returning stale time data.
For sites that are really concerned about accurate time sources, the better approach is multiple GPS receivers with NTP or ACTS (dial-up) as backup.
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makes some good units - I like the NTS-200. Curiously, they only provide for the lightning rod^D^D^D GPS antenna to be connected via coax; no fiber extenders available.
MicroSith refuses to sell any version of Windows 2000 other than the original one with all the bugs and security holes.
MicroSith insists that you connect to the internet in order to access windowsupdate.microsoft.com to get the bug fixes and security patches that make it (somewhat) safe to connect to the internet.
As of last week there were 63 separate updates for Windows 2000, requiring over a gigabyte of downloading and dozens of reboots. (Many of these combine a bunch of previous updates, so the total number of bugs and security holes is far higher.)
I look forward to the day when I find a Linux substitute for those last few Windows apps and am able to stop dual-booting.
If you're installing Windows 2000 quite often, it might be worth your time to google "Slipstream Windows 2000."
"Slipstreaming" is a term someone made up for the process of putting all the updates into a copy of the Windows install CD so that when you install Windows you get all the updates installed during the Windows install.
I've never done it myself, but it sounds convenient for people who regularly reinstall Windows.
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