How to share internet with 1 port ADSL modem router ?

[Peter]

I just get a 1 port ADSL modem router from the ISP. From the specification,
it says that I can use it for Internet sharing.

However, as there is only 1 port (1 port for connecting ADSL signal and 1
port for Ethernet), I would like to know why they say that modem is a router
? From my basic understanding, a router should connect more than 1 machine.

Thanks

 

[RalfG]

Not neccessarily. ADSL modems with a single output connection can have
routing built in as well.. got one. You attach a switch to the modem to
handle multiple connections. Routing has to be turned on in the ADSL modem
though. Often the default modem setting is bridge mode, which does not do
routing. If that's the case, or if you want wireless access, it is not much
more expensive to simply attach an external router to the modem.