[c-nsp] Per packet load balancing with low latency applications

Fri Jan 16 12:32:41 EST 2009

Thanks for your reply.  I would agree with you and I've never had an issue 
with it regarding voice or normal data.

tv
----- Original Message ----- 
From: "Oliver Boehmer (oboehmer)" <oboehmer at cisco.com>
To: <mauritz at three6five.com>; <cisco-nsp at puck.nether.net>
Sent: Friday, January 16, 2009 1:12 AM
Subject: Re: [c-nsp] Per packet load balancing with low latency applications

> Nope. even if the sender doesn't fragment packets, the receiver will
> still make sure packets are put into the correct order (MLPPP considers
> all frames being "fragments" and numbers them accordingly).
> I think disabling fragmentation can lead to slightly increased latency
> (and possibly jitter), for example when a 1500 byte and a 40 byte
> packets are sent in this sequence, and the receiver needs to wait for
> the 1500 byte packet to arrive completely before forwarding the small
> packet..
> I wouldn't consider MLPPP as being especially CPU-hungry these days..
>
> oli
>
> Mauritz Lewies <> wrote on Thursday, January 15, 2009 21:59:
>
>> But then you might as well use per-packet load balancing...
>>
>>
>>
>> On Thu, 2009-01-15 at 14:37 -0600, Tony Varriale wrote:
>>
>>> Turn off fragmentation.  You'll see your CPU drop way down.
>>>
>>> tv
>>> ----- Original Message -----
>>> From: "Andrew Jimmy" <good1 at live.com>
>>> To: <mauritz at three6five.com>; <cisco-nsp at puck.nether.net>
>>> Sent: Thursday, January 15, 2009 2:02 PM
>>> Subject: Re: [c-nsp] Per packet load balancing with low latency
>>> applications
>>>
>>>
>>>> I'm using MLPPP along with CRTP on Juniper routers (using AS PIC),
>>>> And it is working like a charm... yea true MLPPP stuff is
>>>> complicated on Cisco devices which is CPU hungry ...
>>>>
>>>> -----Original Message-----
>>>> From: cisco-nsp-bounces at puck.nether.net
>>>> [mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of Mauritz
>>>> Lewies Sent: Friday, January 16, 2009 12:40 AM
>>>> To: cisco-nsp at puck.nether.net
>>>> Subject: Re: [c-nsp] Per packet load balancing with low latency
>>>> applications
>>>>
>>>> Hi
>>>>
>>>> Out of personal experience MLPPP sounds great in theory and
>>>> technically should be a viable solution. However, Cisco has never
>>>> really been able
>>>> to deliver a bug free MLPPP implementation...
>>>>
>>>> We have had situations of per-packet, moving to MLPPP, going back to
>>>> per-session and eventually having to aggregate into larger single
>>>> links. IOS has just never really worked with MLPPP and I strongly
>>>> advise against.
>>>>
>>>>
>>>>
>>>>
>>>> On Thu, 2009-01-15 at 08:08 -0800, Yan Filyurin wrote:
>>>>
>>>>> Look for ways to aggregate multiple physical circuits into one
>>>>> logical
>>>> that has a native way to load balance and still insure that packets
>>>> are not out of sequence like MLPPP or  MLFR since they have their
>>>> own sequencing that prevents out of order arrival, not to mention a
>>>> bunch of things like fragmentation and interleaving that is great
>>>> for voice.   As far as market data application goes, is it by any
>>>> chance multicast and UDP, which could potentially make it subject
>>>> to the same constraints as voice. You could always do all kinds of
>>>> things to influence various types of traffic going over just a
>>>> single link with redundancy and all or just do per destination. I
>>>> would vote for MLPPP.
>>>>>
>>>>> Like the previous email said, you can use L3 technologies such as
>>>> tunneling with sequence datagrams, but all it will do is drop
>>>> packets that are out of order, thus moving the problem further from
>>>> the application, but still creating it. I've only read about it.  I
>>>> am sure everyone here will vote for MLPPP.
>>>>>
>>>>> Yan
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> ________________________________
>>>>> From: William <willay at gmail.com>
>>>>> To: Brad Hedlund <brhedlun at cisco.com>
>>>>> Cc: "cisco-nsp at puck.nether.net" <cisco-nsp at puck.nether.net>
>>>>> Sent: Thursday, January 15, 2009 10:16:56 AM
>>>>> Subject: Re: [c-nsp] Per packet load balancing with low latency
>>>>> applications
>>>>>
>>>>> Hi Brad,
>>>>>
>>>>> Thanks for your input.
>>>>>
>>>>> Is there anything else I can use to achieve my goal? I'm pretty
>>>>> sure getting a bigger circuit will be a last resort.
>>>>>
>>>>> Regards,
>>>>>
>>>>> W
>>>>>
>>>>> 2009/1/15 Brad Hedlund <brhedlun at cisco.com>:
>>>>>> On 1/15/09 6:25 AM, "William" <willay at gmail.com> wrote:
>>>>>>
>>>>>>> My
>>>>>>> question is what would cause the packets to arrive out of
>>>>>>> sequence?
>>>>>>
>>>>>> Path #1 might have a little more congestion than Path #2, which
>>>>>> would cause Packet #1 sent down Path #1 to sit in a buffer an
>>>>>> extra millisecond or two than Packet #2 sent down Path #2 with no
>>>>>> congestion.  This results in Packet #2 arriving at the
>>>>>> destination before Packet #1.  The result of this being poor
>>>>>> application performance.
>>>>>>
>>>>>> Cheers,
>>>>>>
>>>>>> Brad Hedlund
>>>>>> bhedlund at cisco.com
>>>>>> http://www.internetworkexpert.org
>>>>>>
>>>>>>
>>>>>>
>>>>> _______________________________________________
>>>>> cisco-nsp mailing list  cisco-nsp at puck.nether.net
>>>>> https://puck.nether.net/mailman/listinfo/cisco-nsp
>>>>> archive at http://puck.nether.net/pipermail/cisco-nsp/
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> cisco-nsp mailing list  cisco-nsp at puck.nether.net
>>>>> https://puck.nether.net/mailman/listinfo/cisco-nsp
>>>>> archive at http://puck.nether.net/pipermail/cisco-nsp/
>>>> _______________________________________________
>>>> cisco-nsp mailing list  cisco-nsp at puck.nether.net
>>>> https://puck.nether.net/mailman/listinfo/cisco-nsp
>>>> archive at http://puck.nether.net/pipermail/cisco-nsp/
>>>>
>>>> _______________________________________________
>>>> cisco-nsp mailing list  cisco-nsp at puck.nether.net
>>>> https://puck.nether.net/mailman/listinfo/cisco-nsp
>>>> archive at http://puck.nether.net/pipermail/cisco-nsp/
>>>
>>> _______________________________________________
>>> cisco-nsp mailing list  cisco-nsp at puck.nether.net
>>> https://puck.nether.net/mailman/listinfo/cisco-nsp
>>> archive at http://puck.nether.net/pipermail/cisco-nsp/
>> _______________________________________________
>> cisco-nsp mailing list  cisco-nsp at puck.nether.net
>> https://puck.nether.net/mailman/listinfo/cisco-nsp
>> archive at http://puck.nether.net/pipermail/cisco-nsp/
> _______________________________________________
> cisco-nsp mailing list  cisco-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/ 