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Re: Determine available upload/download bandwidth

From: Nathan Rosenblum <flander_at_gmail.com>
Date: Fri, 29 Nov 2013 13:37:27 -0800

On Thu, Nov 28, 2013 at 1:35 PM, Daniel Stenberg <daniel_at_haxx.se> wrote:

> On Tue, 26 Nov 2013, Sandeep Sastry wrote:
>
> I am looking for suggestions and solutions on determining available
>> bandwidth before uploading or downloading.
>>
>
> There's no way and for an application there's no fixed available bandwidth
> - ever.
>
> What does available bandwidth mean? At every possible moment in time you
> can fire up something else in the background that changes the conditions
> for your particular application and gives it more or less than it had the
> second before.
>
> Is "available bandwidth" what you managed to transfer 10 seconds ago? What
> you managed to use yesterday? If so, then just count that and use in the
> future. If it isn't, you need to adjust dynamically for the conditions you
> get while doing the transfer. Or let the user set the limits based on some
> knowledge about the physical pipe he/she uses.
>
>
It's worth pointing out that there have been methods developed for
estimating the BDP of a network link from a single endpoint. However, some
of these methods are patent encumbered (see e.g.
http://www.patentstorm.us/applications/20070081561/description.html), so
their usefulness to you may vary.

Best,

--nate

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Received on 2013-11-29