By Peter J. Brown

The centuries old Silk Road in Central Asia is by no means forgotten, and yet, it is the IPv6 over satellite traffic on the virtual silk highway that is drawing considerable attention these days. The SILK satellite network provides a direct link between several Central Asian and Caucasian research networks and the European research networks such as GEANT.

In September at the European Space and Technology Centre (ESA/ESTEC) in the Netherlands, a live demonstration of video and audio conferencing using native IPv6 over satellite was conducted via the SILK teleport in Hamburg.

What advantages does IPv6 bring to the table? When it comes to advanced mobile and more secure IPSEC-driven services, it is more user friendly. It encompasses an enormous address space enabling every user, device and vehicle to tap into multiple IP addresses. Because IPv6 does not require the use of Network Address Translation (NAT), it enables the creation of supercharged wireless peer-to-peer services, along with much better service integration for things like VoIP, SIP and H.323, to name a few. When matched with Multimedia Home Platform (MHP), for example, IPv6 expands the interoperable frontier via a more robust plug-and-play environment, which impacts a wide range of consumer premises equipment and home entertainment hardware.

For the SILK demo, several IP/DVB encapsulators and receivers were upgraded to support native IPv6 over satellite. Under an ESA contract, IP/DVB ODG gateways from GCS and 6wind were upgraded. Off-the-shelf DVB-S cards from Pentamedia and TechnoTrend were modified, and in some cases, the modifications have been returned as open source to the Linux community. Other vendors who upgraded include Thales, DataPlanet and UDCast.

Throughout late 2004, the operators of the SILK network continue to experiment with the IPv6 service via established IPv6 networks, according to Frank Zeppenfeldt, ESA/ESTEC technical officer in the directorate of applications/telecommunication. This is all part of a much broader effort supported by ESA involving a future transition from IPv4 to IPv6.

According to Zeppenfeldt, the proposed method of encapsulation, which is now a proposed Internet draft, would support transport of not only IPv6 and IPv4 in a more elegant way than the old Multi

Protocol Encapsulation (MPE) method as proposed by the DVB Forum, but it would also allow the transport of Multi Protocol Label Switching (MPLS) or other future protocols over DVB-S, in order to implement ISP trunking links, for example.

Zeppenfeldt raises a number of issues that have to be addressed by the satellite industry before IPv6 can be widely deployed. Hot on the list are all the Performance Enhancing Proxies (PEP) that are used to accelerate TCP/IP traffic over satellite links. PEPs need to be upgraded to do things like support multiple headers because, according to Zeppenfeldt, in many cases all they do is just block IPv6 traffic. IPv6-capable PEPs are already surfacing.

With Euroconsult estimating approximately 640 transponders are currently in use for Internet trunking applications, primarily in regions where IPv4 address space is already scarce, the deployment of IPv6 in those regions could provide unlimited address space to emerging ISPs.

Besides the SILK network, an evaluation of IPv6 over satellite is under way in Asia as part of the Asia Broadband Program launched last year using the regional satellite-based R & D network known as the AI3 Project. Hidetaka Izumiyama, director of Tokyo-based Wishnet Inc., reports that his company has an IPv6 R&D contract until 2006 with the Japanese Ministry of Internal Affairs and Communications (MIC) and is using JCSAT 3. The IPv6 test deployment is proceeding as planned, according to Izumiyama. Wishnet is collaborating with universities and research institutes in Japan, Indonesia, Malaysia, the Philippines, Singapore, Thailand and Vietnam.

This IPv6 over satellite test involves DVB-S UniDirectional Link Routing (UDLR) feeds and receivers, and it will probe, among other things, the performance of IPv6-ready large- scale multicasting, dynamic band assignment and management technologies. This entails both a point-to-point backbone solution using a Layer-2 bridge with dynamic bandwidth allocation as well as a DVB-RCS solution where IPv6 tunnel over DVB-RCS (IPv4) with a UDLR feed and receiver.

Elsewhere in the world, there was much multimedia in motion as Telesat announced that Anik F2 was fully operational as of early October. MBCO in Tokyo said at our press time that it was ready to go with the Digital Multimedia Broadcasting (DMB) service in Japan via the MBSat satellite in October.

Mark Forward, project manager for Project PROBE in New Zealand, reported that the PROBE satellite contract had been signed with ICONZ in October. It will provide 63 school sites around the country with basic 64k IP service via NSS 5, along with bandwidth on demand available to support 512k videoconferencing when required. ICONZ plans to migrate PROBE to IPStar-1 after it launches. Each site also supports a local community wireless service, according to Forward.

Peter J. Brown is Via Satellite’s Senior Multimedia & Homeland Security Editor. He also volunteers as a satellite technology and communications advisor to the Maine Emergency Management Agency.