updated 05:50 pm EST, Wed November 9, 2011
Pilot begins to address IP address shortage
Comcast has begun piloting technical trials for its implementation of the IPv6 Internet addressing standard. The new standard has been defined and created to overcome a looming shortage of IP addresses that form the foundation of the Internet. The initial pilot will take place in selected California markets.
IPv6 is a follow-on to the old IPv4 IP standard. IPv4 uses 32 bits for the addresses used in Internet communications. This represents about 4.3 billion unique IP addresses. Unfortunately, the rapid growth of web-connected devices is quickly depleting this supply. Current estimates have the supply of available IPv4 addresses being exhausted by mid-2014.
The IPv6 standard uses 128 bit addressing, which offers a much larger pool of IP addresses. The added capacity also provides for more efficient data routing. IPv6 and IPv4 run in parallel; either two networks must be maintained, or traffic of one type must be encapsulated and tunneled within the other.
Comcast has chosen to use a "native dual stack" approach. This means that the cable provider will give customers both IPv4 and IPv6 addresses rather than tunneling or conducting large-scale NAT (Network Address Translation) like a router. Comcast believes that this will be more efficient and faster for users.
Comcast will initially use IPv6 to connect single devices, such as a computer directly to a cable modem that also supports the standard. In December or early 2012, Comcast will expand the pilot to include home gateway devices such as routers.