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Use hierarchical management system to reduce management complexity
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| Layer | Responsibility |
|---|---|
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(one for each individual operator) | end-to-end QoS control, end-to-end resource/path planning |
|
(Bandwidth Broker) |
allocate resources of a core-network to the QoS Manager of all resource
mediators,
e.g. Ingress Router in a Core Network or RRM in a 3G Access Network. |
|
Core-Network QoS Control (One for each Ingress) |
execute QoS policy of core network,
e.g. admission control, load control, routing and path selection, packet scheduler, etc. |
| DiffServ | execute the QoS policy designated by the upper layer manager |
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Admission controllers of a core-network controls per-flow QoS , However
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is not able to offer QoS independently
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is not able to handle real time resource allocation
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BBQ uses resource pre-allocation approach
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pre-allocate resources to edge routers
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Ingress Router plans some pathes of different QoS levels (quality entropy)
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Admission controller obtains/reserves a path of proper quality for each request
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When the resource level is low, ask for more resources from central pool
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This architecture is reservation based (good for QoS), and
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overhead is minimum because real time computation is minimized
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requires stable networks that has seaonal traffic patterns
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needs to compensate the efficiency degradation due to prediction errors
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