Copyrights, Internet investment, consumer choice in entertainment and even freedom of religion are all at stake in the debate over network neutrality, speakers said Thursday during a U.S. Federal Communications Commission hearing at Stanford University.

"The dynamic Internet, perhaps the most expansive and liberating technology since the printing press, is, in fact, under threat,” said FCC Commissioner Michael Copps. “We will keep it open, we will keep it free, only if we act forcefully to make that happen."

Other commissioners and speakers at the hearing differed with Copps, one of two Democrats on the commission, in a discussion that featured a variety of views but drew loud applause mostly when advocates of neutrality rang alarms against carriers and cable operators blocking applications and content.

The event, the agency's second public hearing this year on network neutrality, took place in the wake of revelations about Comcast blocking peer-to-peer file sharing by its customers. The cable operator said it did so to manage congestion for the good of all its customers. Comcast said Tuesday that it was working with Pando Networks to come up with more fair ways to control network congestion. But invitations to the hearing sent to Comcast and other major service providers were declined, FCC Chairman Kevin Martin said. The FCC invited Comcast CTO Tony Werner less than 48 hours in advance, according to Comcast spokeswoman Sena Fitzmaurice.

Commissioners Deborah Taylor Tate and Robert McDowell warned against excessive government intrusion in the Internet. But Stanford law professor Lawrence Lessig argued that neutrality is the conservative approach to the issue. The Internet was designed to be transparent and open, so "anybody can do anything," and it has created enormous economic growth the way it is now, he said.

"Before we allow it to change, the burden should be on those who would change its architecture," Lessig said. Fear of application blocking or slowing will hurt investment in future Internet applications, he said.

Robb Topolski, a software quality engineer who identified the Comcast practice that has come under fire, said the company blocks peer-to-peer traffic 24 hours a day, not just when its network is congested, and hasn't stopped the practice. Topolski said he discovered it when he tried to share recordings of public-domain barbershop harmony songs using Gnutella technology. The blocking hasn't stopped, he said.

The IDG News Service is a Network World affiliate.