New CableLabs® DOCSIS® 3.0 Release Supports IPv6
By William "Scott" Beall,
Systems Analyst and Network Administrator, Innofone.com, Inc.

The new DOCSIS® (Data Over Cable Service Interface Specification) version 3.0 was released by Cable Television Laboratories, Inc., Cablelabs® on Aug. 7, 2006.

What is DOCSIS?
DOCSIS is the most widely used and robust specification that defines the requirements for data over cable systems. It (or one of its variants) is used to permit high-speed data transfer over existing hybrid fiber and coaxial cable television systems, and to connect data devices such as modems, set-top boxes and HDTV decoders over such cable systems.

DOCSIS was created by the Cable Television Laboratories, Inc. under the Cablelabs trademark and has been modified for use in Asia and Europe. This consortium includes some of the largest cable equipment manufacturers and cable providers. Cablelabs also offers certification to hardware manufactures to verify compliance with the DOCSIS specifications.

Who is Cablelabs?
Cablelabs is the trademark of the Cable Television Laboratories, Inc, a non-profit research and development consortium of the North and South American cable television industries. It was formed in 1987, and now has approximately 50 international members.

DOCSIS® 3.0 includes a specification for IPv6, which will allow cable providers to provide higher throughput, advanced security, and better connectivity to the IPv6 segments of the Internet. Many issues related to IPv6 running over broadband have been resolved by this work. Authors of the specification include Ralph Droms, Madhu Sudan, Harsh Parandekar, and Toerless Eckert of Cisco Systems; Margo Dolas and Steve Muller of Broadcom; Dan Torbet and Doc Evans of ARRIS; Diego Mazzola of Texas Instruments; Deepak Kharbanda and Amol Bhagwat of Cablelabs; Ryan Ross of Juniper; Michael Patrick of Motorola; and many other members of the IPv6 Focus Team and the IP Multicast Focus Team.

Comparing current broadband downstream bandwidths looks as follows:

• DSL – up to 10 Mbps
• Dedicated fiber – up to 30 Mbps
• Cable (with DOCSIS 1.0 and 1.1) – up to 10 Mbps
• Cable (with DOCSIS 2.0) – up to 30 Mbps
• European CABLE (with European variant of DOCSIS 2.0) – up to 51 Mbps
• Cable (with DOCSIS 3.0) – up to 160 Mbps

DOCSIS and IPv6
The recent announcement about the release of version 3.0 shows that the cable industry is looking toward the future. Hopefully, DOCSIS 3.0 will force the entire broadband industry to implement IPv6 in its next generation of products, and to demand that the Internet backbone providers enable or add IPv6 to their networks. Once the basic infrastructure is in place, those who do not move quickly to implement and support the next generation Internet protocols will not be competitive and probably will not survive in the broadband arena. Cable modems capture a large share of broadband connectivity in the U. S.; the new specification will allow a major part of the general public to take advantage of the "The New Internet." Announcements by all the major OS (Operating System) manufacturers have shown that they already support native IPv6 or plan to do so in the near future.

The United States Federal Government has mandated backbone compatibility with IPv6 for the federal infrastructure. Unfortunately, the U.S. is running behind the rest of the world in the development, deployment, and implementation of IPv6. Many European and Asian nations have already mandated and implemented IPv6, and appear to have an advantage in the development of New Internet applications. It is to be hoped that the inclusion of IPv6 capability in cable networks will force the cable providers to upgrade their infrastructures and become the moving force that will drive hardware manufacturers and software developers to create new devices and applications that will enable end users to take advantage of the benefits of IPv6.

The worldwide cable infrastructure has over 90 million end users. U.S. cable companies have spent the time and money to build the fastest and most reliable end user connectivity on the Internet. DOCSIS 3.0 should provide a major upgrade that will allow cable providers to give better and faster access to new technologies, including VOIP, VOD, and IPSec.

EuroDOCSIS® 3.0 is the European implementation of the DOCSIS standard, and follows the CableLabs DOCSIS 3.0 standard very closely. Since many places in Europe already have IPv6 infrastructure in use, and many more are planned, this new specification may allow the European communities to take advantage of IPv6 more quickly than the United States, unless the US changes its course quickly and plays catch-up.

IPv6 features of DOCSIS 3.0 include:

• Stateful DHCPv6
• Dual stack IPv4 and IPv6
• IPv6 Multicast
• Encrypted Multicast, MLD for IPv6
• TFTP, IPv6
• Source Address verification, native IPv6
• IPv6 Neighbor solicitation
• IPv6 Router solicitation
• IPv6 Neighbor advertisement
• Transparent IPv6 connectivity to other devices
• Management of modems over IPv6
• Alternative provisioning mode (allows either IPv4 and IPv6)
• IPv6 Solicited node multicast
• IPv6 Subscriber Management
• IPv6 SNMPv3
• Multiple channel bonding (allowing multiple up and downstream channels to be concurrently used by a single subscriber)

Standard cable television will benefit from the new standard, as will other capabilities, including HDTV and the new generations of STBs (Set-top Boxes). With the new transparent connectivity to other devices in the specification, it may be possible for any device with an IP stack to communicate through a cable modem to the Internet, all through IPv6. As the very large number of devices that need to have their own Internet addresses comes online, the need for IPv6 support in the main connections to the Internet will become more urgent, and DOCSIS 3.0 is a major step to avoid future address shortage (and other) crises.

As with many specifications, DOCSIS is not totally comprehensive – it embodies some but not all of the elements of the IPv6 specification, RFC 2460. It will in turn – because of the large number of its users – have a profound effect on the other implementations and definitions that form "the New Internet."