I think the iNavX developer commented that it would work in the configuration on our boat in this thread:

http://www.panbo.com/archives/2010/03/nmea_0183_over_ethernet_on_mar_azul.html

You would need the single port Moxa Nport 5150 and a WiFi router.

If you plan to run a PC all the time, then I think it could be done in software with:

http://www.siitech.com/prod_as.htm

or

http://www.navmonpc.com/

Bob, I think Tom is hoping for a solution without a PC in the middle. Which would be neat, if possible???

Ben and Tom,

The first option I mentioned does not need a PC. It does assume the AIS source is NMEA 0183. Hook the AIS feed to the Moxa 5150. Connect the Moxa to a WiFi router. You're not really using the "router" but you are "bridging" the WiFi to wired ethernet.

Moxa does make a direct to WiFi version of their serial server, but it costs more than the 5150 version plus an inexpensive router.

If you want Internet Access for the Ipad too, then use a Cradlepoint and your favorite cellular company USB modem. (check Cradlepoint for compatibility)

I know that MacENC will relay the GPS and AIS to iNavX. But it requires a computer to be running.

The best option to interface any NMEA data including AIS to an iPad or iPhone is the iMux from Brookhouse ..

http://brookhouseonline.com/imux.htm

Now if you do plan to have a PC or Mac aboard then you can use any number of Mac or Windows applications to have the PC or Mac broad cast NMEA data including AIS to an iPad or iPhone.

Several connectivity options discussed here ..

http://www.macsailing.net/fbb/showtopic.php?tid/1178/