In other postings, I've seen that there are serial to wifi converters. I don't own one, but here are some sellers the unit (I assume they are all made by the same manufacturer):
- Error, Electronic & Electronics Components Depot United States
- http://www.ebay.com/itm/Serial-ttl-RS232-to-802-11-b-g-n-Converter-Embedded-WiFi-Module-CE-FCC-W-Antenna-/110930747193?pt=US_Radio_Comm_Antennas&hash=item19d3fcdf39
- http://www.ebay.com/itm/WIZNET-Ultra-Low-Power-Serial-to-WiFi-Module-/110856553127?pt=Model_Kit_US&hash=item19cf90c2a7
- http://www.ebay.com/itm/Serial-TTL-UART-USB-I2S-GPIO-to-WiFi-802-11-b-g-n-SMT-module-CE-FCC-SMD-USB-/120963346394?pt=US_Cordless_Telephones_Handsets&hash=item1c29fa2fda