A communication system according to the present invention includes a first communication device having a first digital signal processor and a first codec and a second communication device having a second digital signal processor and a second codec. The second communication device is communicatively coupled...http://www.google.es/patents/US6240166?utm_source=gb-gplus-sharePatente US6240166 - LAN connection using analog modems via telephone wiring
LAN connection using analog modems via telephone wiring
