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So you know weighted fake queuing scheduling algorithm packets are classified based on flows rather

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than classes.

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So a flow classification would be done as an example and source and destination IP address.

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The protocol and a port number.

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The idea with weighted fake queuing is that a weight is added to a flow based on different criteria

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such as IP precedence or RSVP which is resource reservation protocol.

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Waited for queuing However prior to rises smaller packets over larger packets.

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So it's a fairer queuing algorithm in that it provides a better quality of service for small packets.

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Small packets are generally used for interactive sessions so as an example of voice packet may only

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be 20 bytes in size whereas an empty packet could be fifteen hundred points in size so larger payloads

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or larger packets are generally sent by data applications.

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Interactive applications such as Telnet to its S H or voice tend to have smaller packets so weighted

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for queuing prior to rises.

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Smaller packets over larger packets and you can increase that pro translation by adding a weight to

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smaller packets based on IP precedents as an example.

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So in brief a voice packet that's 20 bytes.

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If it has an IP precedents of five will appear to be four bytes in size.

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In other words 20 bytes divided by five.

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It appears to be smaller and therefore is proud to rise over large data packets so it uses a clever

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scheduling algorithm to poor tries smaller interactive packets which you can make appear even smaller

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by increasing the IP precedents of the packet so that smaller packets are transmitted before larger

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packets.

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The problem with weighted fake queuing is it doesn't provide bandwidth guarantees.

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So as an example FTB could starve HDP traffic data flows can stall out one another so therefore Cisco

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developed class based weighted fake queuing where you can guarantee bandwidth to specific classes and

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provide dynamic fairness of other flows.

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It's a class based way to fix queuing essentially allows you to create different classes where you can

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specify a minimum bandwidth for specific classes of traffic and waited for queuing could be used on

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the best effort class to ensure that traffic is handled fairly in the best effort.

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Class.