The 11-day conference, seeking to update codes last reviewed when the Web was virtually unknown, highlights the fundamental shift from tightly managed telecommunications networks to the borderless sweep of the Internet.
Some at the Dubai conference, including a 123-member U.S. delegation with envoys from tech giants such as Google Inc. and Microsoft Corp., worry that any new U.N. oversight could be used by nations such as China and Russia to justify further tightening of Web blocks and monitoring.
"Love the free and open Internet? Tell the world's governments to keep it that way," said a message on the main search page of Google.com with a link for comments directed to the Dubai conference, which opened Monday.
The agenda for the gathering of more than 1,900 participants from 193 nations covers possible new rules for a broad range of services such as the Internet, mobile roaming fees and satellite and fixed-line communications. Questions include how much sway the U.N. can exert over efforts such as battling cyber-crimes and expanding the Internet into developing nations.
The secretary-general of the U.N. International Telecommunications Union, Hamadoun Toure, said that accusations that the meeting could limit Web freedoms are "completely untrue" and predicted only "light-touch" regulations.
"Many countries will come to reaffirm their desire to see freedom of expression embedded in this conference," he told reporters.
But the head of the American contingent, Ambassador Terry Kramer, said the U.S. would propose taking all Internet-related discussions off the table and concentrating on already regulated services such as phone networks.
"What we don't want to do is bring in all the private networks, the Internet networks, the government networks, etc.," he told The Associated Press. "That opens the door to censorship."
The outcome of the Dubai gathering is far from certain.
More than 900 proposed regulatory changes have been proposed, but details have not been made public. Broad consensus is needed to adopt any items - the first major review of the U.N.'s telecommunications protocols since 1988, well before the Internet age.
The gathering is also powerless to force nations to change their Internet policies, such as China's notorious "Great Firewall" and widespread blackouts of political opposition sites in places including Iran and the Gulf Arab states. Last week, Syria's Internet and telephone services disappeared for two days during some of the worst fighting in months to hit the capital, Damascus.
Kramer told reporters last week in Washington that all efforts should be made to avoid a "Balkanization" of the Internet in which each country would impose its own rules and standards that could disrupt the flow of commerce and information.
"That opens the door ... to content censorship," he said.
The International Trade Union Confederation, representing labor groups in more than 150 countries, claimed a bloc that includes China, Russia and several Middle East nations seeks to "pave the way for future restrictions on both Internet content or its users."
"It is clear that some governments have an interest in changing the rules and regulations of the Internet," the confederation said in statement Monday.
Another battle that will likely take place in Dubai is over European-backed suggestions to change the pay structure of the Web to force content providers - such as Google, Facebook Inc. and others - to kick in an extra fee to reach users across borders.
"Potentially, the content developers - they could be Googles, they could be universities - would end up being charged potentially to have traffic sent abroad," said Kramer in Dubai. "Either way, you slow down Internet traffic and you actually exacerbate the digital divide, the income divide, because you have a lot of people who are accessing things for free."
Advocates of the changes say the money raised could pay to expand broadband infrastructures in developing countries.
Toure said he hoped for a "landmark" accord on trying to bring broadband Internet to developing countries. "The Internet remains out of reach for two-thirds of world's people," said Toure, who is from Mali.
The U.N. telecommunications agency dates back to 1865, when the telegraph revolutionized the speed of information. Over the decades, it has expanded to include telephone, satellite and other advances in communications.