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So in a weighted fake queuing scheduling algorithm, packets are classified based on flows rather than

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classes.

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

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Address the protocol and a port number.

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The idea with waited for queuing is that a weight is added to a flow based on different criteria such

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

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Weighted for queuing, however, prioritises smaller packets over a 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, says an example.

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A voice packet may only be 20 bytes in size, whereas an FTP packet could be 1500 points in size.

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So larger payloads or larger packets are generally sent by data applications.

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Interactive applications such as TELNET or its s, h or voice tend to have smaller packets, so weighted

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for queuing priority rises, smaller packets over larger packets, and you can increase that prioritisation

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by adding a weight to smaller packets based on IP precedence as an example.

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So in brief, a voice packet that's 20 bytes, if it has an IP precedence of five, will appear to be

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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 prioritized over large data packets.

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So it uses a clever scheduling algorithm to prioritize smaller interactive packets, which you can make

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appear even smaller by increasing the IP precedence of the packet so that smaller packets are transmitted

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before larger packets.

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

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So as an example, FTP could starve HTTP traffic data flows can starve out one another.

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So therefore Cisco developed class based weighted fare queuing where you can guarantee bandwidth to

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specific classes and provide dynamic fairness of other flows.

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So class based weighted for 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 to class.