Fundamental questions regarding Multi-WAN, Multi-LAN Traffic Shaping

  • Hi Everyone,

    We have 3 WANs, 4 LAN subnets and a DMZ subnet. Our traffic shaping need is very basic - mainly giving outgoing and incoming voice/video real-time communication highest priority, then screen-sharing, then HTTP traffic and then other traffic.

    Here's my questions:

    1. The traffic shaper wizard for Multi-WAN/Multi-LAN produces queues for each LAN. We don't have need to shape LAN or LAN-to-LAN traffic. We need to only shape traffic coming and going to/from Internet. In that case, does EACH of the LANs need to have its own set of queues? Is it the case that each of those same-named queues must have both LAN and WAN counterparts?

    2. Is it the case that only floating "Match" rules applied on WAN interfaces are sufficient to do traffic shaping (and we don't need queueing rules in the LAN rules)?

    3. Is it always a best practice to have LAN-side traffic shaping on the LAN interface so that higher priority traffic doesn't get congested or randomly prioritized on LAN interface which will cause them arrive in non-ideal order on the WAN interface? Instead, is it not the case that having the queues only on WAN interface will still do intended shaping since the packets anyway get queued up just before going out the WAN interface.

    4. For uploads or outbound data transfers (like outbound voice in a voice chat/call), which queue gets used? WAN queues or LAN queues or both the queues?

    5. If we need to have LAN queues, then since we have multiple WANs, do we have to use one set of qInternet–qAck,qOthersHigh,qOthersLow,etc. for EACH WAN under the LAN root queue?

    I guess these are really the core confusions any newbie would have (apart from understanding HSFC itself). Answers to these questions will greatly help everyone.


  • Good questions. On the "By Queue" tab you'll see that each queue can be associated with multiple interfaces. Like you I'm unclear how available download bandwidth is shared between multiple LANs. Upload is simple as that's defined once, on the WAN interface.

    I'm not sure if the wizard is doing it incorrectly as it shows all LANs as peers at the top level with no common parent. I'd have expected a single download queue with the LANs as children, sharing that bandwidth (assuming that each LAN is faster than the WAN!).


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