Yes indeed! Great work! That is exactly what LFI seeks to accomplish.

Here is some more great info on LFI from the Enterprise QoS Design Guide from 
Cisco Systems

Serialization
Serialization delay refers to the finite amount of time it takes to clock a 
frame onto the physical media. Within the campus, this time is so infinitesimal 
that it is completely immaterial. Over the WAN, however, lower link speeds can 
cause sufficient serialization delay to adversely affect real-time streams, 
such as Voice or Interactive-Video.
Serialization delays are variable because they depend not only on the line rate 
of the link speed, but also on the size of the packet being serialized. 
Variable (network) delay also is known as jitter. Because the end-to-end 
one-way jitter target has been set as 30 ms, the typical per-hop serialization 
delay target is 10 ms (which allows for up to three intermediate hops per 
direction of VoIP traffic flow). This 10 ms per-hop target leads to the 
recommendation that a link fragmentation and interleaving (LFI) tool (either 
MLP LFI or FRF.12) be enabled on links with speeds at or below 768 kbps (this 
is because the serialization delay of a maximum-size Ethernet packet—1500 
bytes—takes more than 10 ms to serialize at 768 kbps and below). Naturally, LFI 
tools need to be enabled on both ends of the link.
When deploying LFI tools, it is recommended that the LFI tools be enabled 
during a scheduled downtime. Assuming that the network administrator is within 
the enterprise's campus, it is recommended that LFI be enabled on the branch 
router first (which is on the far end of the WAN link) because this generally 
takes the WAN link down. Then the administrator can enable LFI on the WAN 
aggregator (the near end of the WAN link), and the link will come back up. 
Otherwise, if the administrator enables LFI on the WAN aggregator first, the 
link will go down, along with any in-band management access to the branch 
router. In such a case, the administrator would need to remove LFI from the WAN 
aggregator (bringing the link back up), enable LFI on the branch router, and 
then re-enable LFI on the WAN aggregator.
Additionally, since traffic assigned to the LLQ escapes fragmentation, it is 
recommended that Interactive-Video not be deployed on slow-speed links; the 
large Interactive-Video packets (such as 1500-byte full-motion I-Frames) could 
cause serialization delays for smaller Interactive-Video packets. 
Interactive-Video traffic patterns and network requirements are overviewed in


From: gaurav nunia [mailto:[email protected]]
Sent: Thursday, July 28, 2011 9:35 AM
To: Anthony Sequeira; [email protected]
Subject: Re: [OSL | CCIE_RS] QOS-basic hrdware Q

EDIt- HQ has one packet place empty, 1(2).  sorry for ambiguity in the 
statement.
On Thu, Jul 28, 2011 at 7:03 PM, gaurav nunia 
<[email protected]<mailto:[email protected]>> wrote:
Thanks,

so that means, we do the queuing actions only on the packets overflowing the 
hardware Q,

one more doubt :)
what happens when the HQ has only one packet in the Q, and transmit Q is 1(2). 
and then occurs a arrival of really big packet.
if LFI is being used, will the packet be fragmented, and the following small 
voice packet, be allowed to pass swiftly.?

On Thu, Jul 28, 2011 at 6:53 PM, Anthony Sequeira 
<[email protected]<mailto:[email protected]>> wrote:
http://stormwindlive.com/blog/?p=179

-----Original Message-----
From: 
[email protected]<mailto:[email protected]> 
[mailto:[email protected]<mailto:[email protected]>]
 On Behalf Of gaurav nunia
Sent: Thursday, July 28, 2011 9:02 AM
To: [email protected]<mailto:[email protected]>
Subject: [OSL | CCIE_RS] QOS-basic hrdware Q

if wrong please correct the following?

1 the hardware Q is always, FIFO,
2. when ever the HArdware Q is empty, or long enough that it seldom fills( i 
change the default from 2 to little high after configuring queuing), then the 
Queuing can't be feasible as hardware Q don't get filled up, and everypacket 
goes to it (although queuing is configured).

if the 2nd statement is true, do the subinterface queues too behave in the same 
manner.

--
thanks
gaurav
<http://routing0sand1s.blogspot.com/>
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--
thanks
gaurav





--
thanks
gaurav

http://routing0sand1s.blogspot.com/
_______________________________________________
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Are you a CCNP or CCIE and looking for a job? Check out 
www.PlatinumPlacement.com

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