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hosts at other end sites through ESnet, Internet2 and regional networks, i.e., NoX (Northern

Crossroads in Boston), and Merit and MiLR (Michigan Lambda Rail) in Ann Arbor.

Implementation:

Ensuring QoS for a path between a source and a destination site requires the coordinated

configuration of the network devices of all domains along that path. The end-site LANs are under

the direct control of a configuring system (in our case, we assume that all end-sites are under the

control of TeraPaths), while WANs have their own admission control system for any traffic other

than best effort. We considered three models for carrying out an end-to-end setup: the star model,

the daisy chain model, and a star/daisy chain hybrid model (see Figure 69). We chose to

implement the hybrid model because it simplifies interoperability between different network

management systems while imposing minimal restrictions on individually managed network

domains.

Figure 69: The three end-to-end setup models.

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