Internet2 Network: Architecture

The architecture of the new Internet2 Network consists of: the national footprint; the connection to the regional optical networks (RONs) and the equipment and interfaces to support those connections; and the ability to support services to the research and education community, including campus researchers and community wide participants.

The hierarchy of the Internet2 Network architecture is similar to previous networks: backbone to regional to campus. However, the network itself is completely different. It is no longer an IP network like those found in the commercial sectors of the Internet. Rather, it is a hybrid network that supports layer 1 dynamic and static services along with innovative new techniques at layer 3. Its most important feature is the ability to experiment with new protocols and ideas for the research and education community.

In defining the architecture, several crucial design goals were considered, including but not limited to:

• Serve all Internet2 members – campuses, affiliates, sponsored participants, SEGPs, and corporate participants – and enhance the ability to serve a wider community. All current RONs are to be supported.
• A hybrid network capable of point-to-point services together with an IP network.
• Every connector (RON) attaches to a backbone ring at a metro location not requiring extensive backhaul.
• The community retains complete control of the layer 1 optical system, including the provisioning and switching of wavelengths and sub channels.
• The community does not have to concentrate on reliability and sparing. The carrier is responsible for an SLA. The carrier provides the operational support, allowing the community to focus on networking. Control of the system is left to the community, allowing the development of new and dynamic services.
• The system is capable of supporting network research in a wide variety of ways, including the ability to set up networks at will for research communities.
• The system is provisioned on fiber that is used by the community and maintained by the carrier. There is significant financial advantage to the community, if the community provides the fiber under an IRU with the carrier.

That the system lies on dedicated fiber has substantial advantages. Dedicated wave equipment currently used by Level 3 will provide the waves for the system. That wave system is provided by Infinera, which supports advanced technologies with substantial add/drop capabilities and significant advantages in provisioning and redundancy. Provisioning a static wave is accomplished by simply installing the endpoint interfaces. This is far different from most current optical systems where many interfaces must be installed along the entire path. Moreover, since the system is completely dedicated to Internet2, it is possible to leap beyond the carrier’s standard offerings to utilize the advanced technology provided by Infinera.

The system will also incorporate a grooming capability – the ability to provide sub channels through waves using either an Ethernet or advanced SONET infrastructure.

The Ciena CoreDirector multiservice switching system will provide point-to-point services down to the campuses through the RONs. The goal is to provide lightpath capabilities provisioned within seconds that last for durations of at least hours.

The topology consists of optical nodes connected by waves maintained by Level 3 that connect to RONs and other participants. The carrier footprint primarily determines the topology of the network, but the use of the Infinera gear allows for great variability in drop/add locations.

The new Internet2 Network design encourages aggregation at the RON layer in the hierarchy.

The IP network, corresponding to the current Abilene backbone, is built on top of the optical network. The IP backbone is provisioned across the waves in the system, and each RON connects to the IP network through the optical system.

Since the carrier provides an SLA for the waves on the system, the IP network will have carrier-quality provisioning, which is expected to be minimally three 9’s (99.9%) uptime, but is likely to be closer to five 9’s (99.999%).

There are substantial redundancy options. The Infinera platform can provide control plane redundancy for IP connectors, and SONET restoration is also a possibility. These options will be determined by consulting the community as a whole.

The IP network will initially use Internet2's existing Juniper routers, which remain state of the art and are capable of migrating to 40 Gbps services.

The architecture provides the capability of providing a variety of circuit (or lightpath) services on the new Internet2 Network, but the agreement provides additional wave provisioning capabilities on the entirety of the carrier’s footprint. Services provisioned on the new network:

• Short Term and Long Term dynamically provisioned circuits
• Long term static, full wave services
• "Off net" services provided by the carrier through “WaveCo,” provisioning circuits – optical carrier and digital signal – for regional networks and other Internet2 participants needing to extend connectivity anywhere the Level 3 optical network reaches. The “off-net” service will be provided at cost-effective, aggregated rates.

Engineering support for the new network will be drawn from members of the community and the Internet2 staff. Building on our experience in designing, developing, and maintaining Abilene, HOPI, and NLR, Internet2 expects operational support to fall into three broad categories: control plane activities and dynamic provision of basic services; application and advanced services support in hybrid networks; and engineering, monitoring and management.