In a converged environment, all types of traffic travel over a single transport

infrastructure. Yet all traffic types are not the same. Data is bursty, loss intolerant,

and not latency sensitive. Voice, on the other hand, is nonbursty and has some

tolerance to loss but is latency sensitive. The challenge is in providing the

required level of service for each of these traffic types.

The goal of protecting voice traffic from being run over by data traffic is

accomplished by classifying voice traffic as high priority and then allowing it to

travel in the network before low priority traffic.

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