5 ms·

so the modem was just connected to a switch?

• EvanAnderson 5y ago
  The router on the OP's network was probably just being a router. No fancy NAT junk, and probably no ACLs / fireballing. It was pretty common to have something like a T1 circuit, a CSU/DSU that connected to the T1 and presented a serial connection, and a PPP or SDLC connection to your upstream ISP over that serial connection. The router's Ethernet interface is connected to your switch (or hub) and all the hosts have IP addresses in the subnet your ISP assigned. Fancier shops might have a proxy server or dedicated firewall box between the LAN and the router.
  • jiggunjer 5y ago
    I see. An ISP subnet isn't really the same as a public IP though?
    • EvanAnderson 5y ago
      Back in the 90s your ISP would have given you a subnet of public IPs to use. I have a Customer w/ a T1 that they've had since the late 90s with the same /26 of public addresses on it the whole time.
• WarOnPrivacy 5y ago
  I had a biz customer who had an early cable internet connection. ISP plugged their dumb modem directly into the hub and every PC had a public IP. This was awesome for about 3 hours until the worms showed up - because Win98 didn't come with a firewall.
• jjav 5y ago
  > so the modem was just connected to a switch? What EvanAnderson said. The office ethernet network just contained a router, which would be hooked up to the upstream (via multiple T1 lines, IIRC). So everything on the office network had a public IP and was directly on the internet.