Step 1: Identifying traffic types and their requirements
Identifying traffic types and their requirements, the first step in implementing QoS, is composed of the following elements or substeps:
Perform a network audit -- It is often recommended that you perform the audit during the busy hour (BH) or congestion period, but it is also important that you run the audit at other times. Certain applications are run during slow business hours on purpose. There are scientific methods for identifying the busy network moments, for example, through statistical sampling
Perform a business audit and determine the importance of each application -- The business model and goals dictate the business requirements. From that, you can derive the definition of traffic classes and the requirements for each class. This step considers whether delaying or dropping packets of each application is acceptable. You must determine the relative importance of different applications.
Define the appropriate service levels for each traffic class -- For each traffic class, within the framework of business objectives, a specific service level can define tangible resource availability or reservations. Guaranteed minimum bandwidth, maximum bandwidth, guaranteed end-to-end maximum delay, guaranteed end-to-end maximum jitter and comparative drop preference are among the characteristics that you can define for each service level. The final service level definitions must meet business objectives and satisfy the comfort expectations of the users.
Go to Step 2: Classifying traffic based on the requirements identified
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