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On 10/13/21 11:29 AM, Adam Thompson wrote:<br>
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cite="mid:YTOPR0101MB0987C90442B71797E4DAD3B69BB79@YTOPR0101MB0987.CANPRD01.PROD.OUTLOOK.COM">
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<style type="text/css" style="display:none;">P {margin-top:0;margin-bottom:0;}</style>I've
got a downstream customer asking for help; they have a private
internal network that I've taken to calling the "partial-mesh
network from hell": it's got two partially-overlapping radio
networks, mixed with islands of isolated fiber connectivity.
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Dynamic routing protocols (IS-IS, OSPF, EIGRP, etc.) generally
will only select the _best_ path, they won't spread the load
unless all paths are equal - and they are very unequal in this
network, ECMP would likely fail horribly.<br>
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The network is becoming bandwidth-limited, so they're wanting to
make use of all available paths, not just the single "best"
path. It's also remote and spread out, so adding new links or
upgrading existing links is difficult and expensive.</div>
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Oh, and their routers are overdue for a refresh, so acquiring
replacement h/w is now possible.<span id="��"></span><br>
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<br>
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Has anyone come across any product or technology that can handle
the multi-path-ness and the private-network-ness like a regular
router, but also provides the intelligent per-flow path steering
based on e.g. latency, like an SD-WAN device (and/or some
firewalls)?</div>
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<br>
Maybe add a little bit of linear optimization on top of
faucet/openvswitch/openflow to calculate best paths based upon
bandwidth, paths, and fill-factors. There is a presentation where
Google uses that technique to obtain high utilization on their links
(not necessarily those tools though).<br>
<br>
Raymond Burkholder<br>
<br>
<br>
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