Re: [6lo-fragmentation-dt] Performance report for fragment forwarding

"Pascal Thubert (pthubert)" <pthubert@cisco.com> Tue, 18 September 2018 17:13 UTC

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From: "Pascal Thubert (pthubert)" <pthubert@cisco.com>
To: Rahul Jadhav <rahul.ietf@gmail.com>, "6lo-fragmentation-dt@ietf.org" <6lo-fragmentation-dt@ietf.org>
CC: "rabinarayans@huawei.com" <rabinarayans@huawei.com>, "yasuyuki.tanaka@inria.fr" <yasuyuki.tanaka@inria.fr>
Thread-Topic: [6lo-fragmentation-dt] Performance report for fragment forwarding
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Date: Tue, 18 Sep 2018 17:13:34 +0000
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Subject: Re: [6lo-fragmentation-dt] Performance report for fragment forwarding
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Yes, I documented that issue when I presented to the 6lo WG. The only protection is to introduce delay between fragments so they get out of interference domain before you send the next one. The next problem is incast in the network, when you start multiple flows that cross/converge at a same intermediate node. My draft allows for flow control by asking an ack every so many fragment…
Take care,
Pascal

From: 6lo-fragmentation-dt <6lo-fragmentation-dt-bounces@ietf.org>; On Behalf Of Rahul Jadhav
Sent: mardi 18 septembre 2018 18:05
To: 6lo-fragmentation-dt@ietf.org
Cc: rabinarayans@huawei.com; yasuyuki.tanaka@inria.fr
Subject: [6lo-fragmentation-dt] Performance report for fragment forwarding

<< turns out my earlier mail didn't reach the ML; trying again >>

Hello all,

We experimented with Fragment Forwarding and tried to understand the performance implications vis-a-vis per-hop reassembly.

Following is the detailed report:
https://github.com/nyrahul/ietf-data/blob/master/6lo-fragfwd-perf-report.md

To summarize, we found that fragment forwarding has some practical issues when it comes to forwarding efficiency or PDR "on single channel 802.15.4". While similar concerns were been raised previously during IETF meetings, we tried to validate it with data.

Please let us know if any comments.

Regards,
Rahul