how does 3G modem talk to Wifi-router

How does 3G modem talk to Wifi-router….is the integration/communucation between these two handled at protocol stack level or at hardware level by means some logic ??

Re: How does 3G modem talk to Wifi-router

a 3G modem cannot communicate using Wifi (802.11a/b/g/n). What you will usually see is that a 3G modem may contain Wifi features, and communicate using 802.11a/b/g/n.

Alternatively, you will see companies (e.g. Linksys or Option) selling routers that contain Wifi and 3G (HSPA/UMTS/GPRS) communication facilities.

The Linksys WRT54G3G router contains PCMCIA slot for 3G datacards, and has built in Wifi connectivity. Newer models are also supposed to have a USB port.

On a lower level, these routers usually run some flavour of Unix (Linux) and the 3G connection is maintained using a PPPOE to your 3G (GPRS/UMTS/HSPA) service provider.

The “link” if you will, between the 3G connectivity and the Wifi connectivity is usually made using a linux feature called ipchains/iptables. This will essentially forward any request from a Wifi client to the 3G service provider gateway via the 3G/PPPOE connection on the router.