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ISA550W - WAN QoS with WRR - how is the Bandwidth calculated?

Hey there,

i have a ISA550W at home that is used as our Internet Router for basic Internet Connectivity. Our Internet-Connection ist not the fastest one (we have ADSL with 2048 KBit/s Downstream and 256 KBit/s Upstream) but we share this connection with up to 4 People in peak times when the whole family is at home.

My brother is a person that does alot on the internet - he Facebooks, he Soundclouds, he Radiostreams - and he downloads like hell. So when he is at home it is 100% Sure that the Internet Connection is extremely slow for anybody else. Because he doesnt limit himself although we told him to do so (i guess he became an Internet Addict that already lives there ^^) i now hard-limited him with the WAN QoS Feature of the ISA to a specific Bandwidth. This works extremly well - he cant do more than 10 KBit/s in the upstream and 800 KBit/s in the Downstream. But obviously he started crying about that and though im not interested in his complaining the owner of our internet connection - my father - is :-/ I therefore have to find a solution to only limit him when we are doing something. And as far as i know i can achieve this with WRR.

So in WRR you can set weights for the Queues each traffic is classified to. Nice feature, seems as if its exactly what i need. But now i thought about it and i found no clue on how the ISA should measure those values. Because: If i enter 80 % for Q1 for example - what 80% does it take? 80% from the capacity of the WAN-Interface (which is connected with 100 MBit/s to the Modem)? Or 80% from the Capacity of the PPPoE Connection? But how does it measure this capacity? I only found a Bandwidth-Limit in the General Settings but this only applies to the Upstream, not the Downstream.

So to make it short now: How does the ISA550W determines the Capacity of the Connection through WAN QoS when WRR is used? What are the percentage values based on? And if they arent based on anything: Where can i set the Limits for it?

Many thanks for your help in advance!



ISA550W - WAN QoS with WRR - how is the Bandwidth calculated?


I found some information that you may find helpful:

Weighted Round Robin (WRR): Traffic is sent from the queues in round-robin fashion. The number of packets sent from a queue is proportional to the weight of the queue. The higher the weight, the more frames are sent. As compared to SP, WRR offers more opportunities for lower queues to transmit.

Basically if there are 10 packets in queue and you choose 80% for Q1 and 20% for Q2, WRR will send 8 packets from Q1 and 2 from Q2. If there are no packets in Q1 and 10 in Q2, WRR will skip Q1 and send 10 packets from Q2. This is probably over simplified but it is the basic idea.

Some documents that describe the configuration:

- Marty

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