By Darren Waters
Technology editor, BBC News website, Athens
The global inter-operability of the internet needs to be preserved, Vint Cerf, one of the founders of the net, has told a global gathering in Athens.
Mr Cerf said the net could shatter into incompatible islands
Mr Cerf was speaking at the first-ever Internet Governance Forum (IGF), a United Nations' creation to bring all the decision makers involved in the internet together.
He said the ability for everyone and every device to connect to the net using a simple protocol was the backbone of the internet.
But changes to the way the net works, to accommodate a multi-lingual internet, raised concerns, he said.
Work is ongoing to allow people around the world to access the net using their own languages and scripts, such as Arabic, Cyrillic and Chinese ideograms.
Mr Cerf said creating a multi-lingual internet, using what are known as internationalised domain names (IDN), was "a huge technical challenge".
Currently all internet users must type in website addresses, called domain names, using the Latin alphabet. Some countries and organisations feel that the drive to a multi-lingual net was proceeding too slowly.
Tarek Kamel, Egypt's minister of communications, said there was an "absence of truly diverse, multi-lingual internet".
The language barrier comes as a "major hindrance to using the internet," he said.
Viviane Reding, the EC's information society commissioner, said: "Bridging the digital divide is not just a matter of screens and cables.
"It is equally important to recognise the extent and value of cultural diversity within global village of the internet. That is why multilingualism is important."
She said that IDN was "sometimes wrongly seen as technical issue".
"There is legitimate political imperative," she said. "Users want to be able to use Chinese ideograms and Arabic scripts.
"There is a real danger that a prolonged delay in the introduction of IDN could lead to fragmentation of the internet name space."
But Mr Cerf, chairman of Icann, the body which oversees the use and development of domain names, said IDN was very much a technical issue.
"One of the most important aspects is for the user to make unambiguous references to every registered domain name.
"Historically this has been through a small subset of Latin characters."
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Each domain name for a website is unique - so that each and every user who types "bbc.co.uk", for example, is sent to the BBC page.
Mr Cerf said that in order for other scripts to be introduced into the domain name system, there needed to be rigorous testing to ensure that users could be certain they will reach their online destination no matter which script they used.
"Domain names are not general natural language expressions. They are simply identifiers," he said. "They must be unique. Names registered today must be able to work into their distant future no matter what characters are added."
He warned: "A miss-step could easily and permanently break the internet into non-interoperable components."
Icann was currently testing the introduction of different scripts into the domain name system, he said.