Increase bandwidth usage in partial-mesh network?

Raymond Burkholder ray at
Thu Oct 14 06:01:14 UTC 2021

On 10/13/21 11:29 AM, Adam Thompson wrote:
> 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.
> 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.
> 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.
> Oh, and their routers are overdue for a refresh, so acquiring 
> replacement h/w is now possible.
> 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)?

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).

Raymond Burkholder

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