Genachowski's office had no comment on the letters.
Meanwhile in the Senate, the top Republican on the Commerce Committee, Kay Bailey Hutchinson of Texas, is considering legislation that would prohibit the FCC from developing net neutrality rules.
Genachowski's proposal calls for the FCC to formally adopt four existing principles that have guided the agency's enforcement of communications laws since 2005. Those principles state that network operators must allow subscribers to access all legal onl　ine content, applications, services and devices.
Genachowski is also calling for the FCC to adopt two additional principles that would prevent broadband providers from discriminating against particular content or applications and would require them to be open about their network management practices. And he is calling for the agency to apply these rules across different types of broadband networks, including wireless networks.