Why rebuilding might make sense

NEW YORK — Government and university researchers have been exploring ways to redesign the Internet from scratch. Some of the challenges that led researchers to start thinking of clean-slate approaches:

Security

Challenge: The Internet was designed to be open and flexible, and all users were assumed to be trustworthy. Thus, the Internet's protocols weren't designed to authenticate users and their data, allowing spammers and hackers to easily cover their tracks by attaching fake return addresses onto data packets.

Current fix: Internet applications such as firewalls and spam filters attempt to control security threats. But because such techniques don't penetrate deep into the network, bad data still get passed along, clogging systems and possibly fooling the filtering technology.

Clean-slate solution: The network would have to be redesigned to be skeptical of all users and data packets from the start. Data wouldn't be passed along unless the packets are authenticated. Faster computers today should be able to handle the additional processing required within the network.

Mobility

Challenge: Computers rarely moved, so numeric Internet addresses were assigned to devices based on their location. A laptop, on the other hand, is constantly on the move.

Current fix: A laptop changes its address and reconnects as it moves from one wireless access point to another, disrupting data flow. Another workaround is to have all traffic channel back to the first access point as a laptop moves to a second or a third location, but delays could result from the extra distance.

Clean-slate solution: The address system would have to be restructured so that addresses are based more on the device and less on the location. This way, a laptop could retain its address as it hops through multiple hot spots.

Ubiquity

Challenge: The Internet was designed when there were relatively few computers connecting to it. The proliferation of personal computers and mobile devices led to a scarcity in the initial address system. There will be even more demand for addresses as toasters, air conditioners and other devices come with Internet capability, as will standalone sensors for measuring everything from the temperature to the availability of parking spaces.

Current fix: Engineers expanded the address pool with a system called IPv6, but nearly a decade after most of the groundwork was completed, the vast majority of software and hardware still use the older, more crowded IPv4 technology. Even if more migrate to IPv6, processing the addresses for all the sensors could prove taxing.

Clean-slate solution: Researchers are questioning whether all devices truly need addresses. Perhaps sensors in a home could talk to one another locally and relay the most important data through a gateway bearing an address. This way, the Internet's traffic cops, known as routers, wouldn't have to keep track of every single sensor, improving efficiency.