Dynamic Bandwidth Detection (BWCheck)

[adumin]

Thanks Richard, but I was aiming at something else.
Suppose I have a myFIle that I send to the user,
and i want to calculate how long it will take for the user to recieve it.
I know my file size, but i dont know what`s the user download speed.
How can I tell the user`s download speed by this data, please ?

[rrlanham]

"latency" is how long will it take to start playing

The speed at which it will play once it starts is indicated by kbitDown

Richard

[adumin]

Thanks Richard so if
kbitDown:1000
it means it loads 1000kbit per second ?
and if , then i want to send a file of 1000kbit to the user
it will be transferred in:
1 second + latency ?

[rrlanham]

There is a kbitDown number and latency number. One is not the other. Obviously this is about re-inventing a way to do Dynamic Streaming, because you said yesterday that you don't think the QoS metrics built-in to Flash using the NetStream.info object are adequate. I really don't agree with that premise. I suggest you backup and take a better look at NetStream.info object. Here is another Adobe article:

http://www.adobe.com/devnet/flashmed...ionscript.html

Richard

[adumin]

You must have had someone else in mind when sending this message, Richard.
Which makes a lot of sense to me, Considering you must be answering such a multitude of questions by so many users.
Please believe me I have no issue with the QoS metrics built-in to Flash, nor the NetStream.info.
I`m simply trying to use this BWcheck module as a means of claculating how long will it take the user to recieve a specific big file (the file`s not being sent with NetStream at all).
Neither did I assume that latency and kBitDown are the same.
I just attempted to determine if the formula for calculating how long a file will take to be transferred (assuming bandwidth is not constant) would be:

Latency + kbitDown*fileSize in kbits

Is my formula correct ?
If not, what would be the right formula, please ?
Also, you said:

"latency" is how long will it take to start playing

The speed at which it will play once it starts is indicated by kbitDown

In what units is measured latency ? seconds ?
and in what units is measured kbitDown? kbits per second ?
Many thanks

[rrlanham]

You must have had someone else in mind when sending this message, Richard.

Oh, whoops, sorry about that. Please excuse me.

Yes, it is in seconds: kbs = kilobits per second. I think the forumula would be:

Latency + fileSize in kilobits / kbitdown

Richard

[adumin]

Please excuse me.

Surely there`s no need for any excuse at all...
Quite the opposite - Thank you for your swift responses and assistance !
Thank you for asserting my assumption about the units AND for correcting my formula. Of course it`s divided and not multiplied.

Again , many thanks - you`ve helped me a great deal.

[adumin]

Please just another question:
Is KILO calculated in the wowza server in standard notation as in 1 Kilobit= 1024 bits or in IEEE notation as in 1 Kilobit=1000bits, please ?

[rrlanham]

I think it is 1024.

Richard

[rrlanham]

But seems like video duration is all you really need. That could be different than your calculations, because Wowza throttles delivery to bitrate.

You can get duration in the metadata in the NetStream NetStatusEvent handler, or more directly by doing:

netconnection.call("getStreamLength, responderName,"example.flv");

Richard