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How can I implement LFI out an Ethernet interface ????


I have couples IP Phones on a LAN. This LAN also contain some web and FTP servers.

This LAN connects to a WAN connection SHDSL 2Mb/s (in fact 1780..).

I haven't any QOS possibility on the modem wich connect the LAN to that SHSDL line. So I 'm thinking of taking action on the IP flow before it gets to the modem to reach the WAN.

So i'm in a situation where I must "format" the IP flows before the point of congestion..

I decided to insert between the LAN and the modem to the WAN link a router with nat and LLQ (LL-CBWFQ).

My outgoing interface on the router is then an .. Ethernet interface.

To force congestion i'm using traffic shaping on the entire interface (ie traffic shaping is configured under that interface configuration level. The traffic shaping is configured to smooth the traffic out to the bandwith of the SHDSL line wich is 1780 Kb/s.

The voice quality is definitively better with the trafic shaping on but.

But, it doesn't really guaranty minimum delay, as it queues overloading packets rather than breaking up larges packets as LFI would do..

Could someone tells me how i could achieve minimum delay on this Ethernet interface so the traffic flow get arranged before it gets to the modem ??

Is there any LFI possibility that i could apply to the Ethernet interface once its bandwith is limited to a "WAN fashion bandwith" ?

Thanks in advance..

Hall of Fame Super Gold

Re: How can I implement LFI out an Ethernet interface ????


beside that at 1780 kbps LFI would not give you anything, as it is above the critical serialization delay for the case a large packet is being transmitted before voice,

it is not supported on Ethernet.

If shaping and QoS are set right you are applying already the best in the upload direction.

Better than that, you can only put a wic g.shdsl in the router and connect to the circuit directly.

Hope this helps, please rate post if it does!