Vinton Cerf has added his name to a campaign begging the FCC to scrap plans to ban custom firmware on Wi-Fi routers and other wireless devices.

The internet pioneer is among 260 signatories on an open letter urging the US watchdog not to pass a proposed package of rules [PDF], formally known as Docket 15-170.

The suggested directives appear to outlaw the use of customized firmware, such as DD-WRT or OpenWRT, on Wi-Fi routers.

The regulator is worried that, by allowing people to load their own software on these gadgets, they can reprogram the radio hardware to broadcast on any frequency they like – certainly outside the range allowed for the devices – and that's a big no-no-no-no for the communications watchdog. To prevent people from wandering off into other radio spectrum without permission, the FCC wants devices to only run firmware signed off by the manufacturers, and thus lock users into licensed frequencies.

"We understand there are significant concerns regarding existing users of the Wi-­Fi spectrum, and a desire to avoid uncontrolled change," reads the protest letter, which was published on Wednesday.

"However, we most strenuously advise against prohibiting changes to firmware of devices containing radio components, and furthermore advise against allowing non-­updatable devices into the field."

The FCC kicked up a firestorm earlier this year when the mulled rules first emerged. The plan has drawn sharp criticism from privacy and software-freedom advocates who worry the regulations will prevent hobbyists and researchers from tinkering with their own routers. One good reason to install custom firmware is to rid your box of any security vulnerabilities present in the code provided by the manufacturer.

The letter signed by Cerf and others insists that the owner of a device should have the freedom to modify the firmware as they wish, and face the consequences if they break the law – as opposed to the FCC's preemptive crackdown.

"The FCC should step back, and prepare rules to enhance the security, reliability, and functionality of the routers that operate home and business networks," the letter reads.

"These rules should increase visibility into the source code that operates these routers, and encourage best software practices to create a better future for billions of Wi-­Fi devices already deployed, and the billions to come, as well as a freer, faster, and safer internet."

The FCC is still mulling over the proposed rules, and won't make up its mind until after November 9. ®