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craigim
2009-09-27, 16:54
My router (Netgear WNR3500) has a 'Quality of Service' setting on it that allows one to set the priority of certain ports to give them more or less bandwidth. I would like to set it up so that my Squeezebox gets high priority when streaming, so that even if I'm backing up my thesis data to my school server, my music doesn't constantly pause to rebuffer if I'm listening to Pandora or other streaming radio. Does that communication happen on port 9000, or is there another port for incoming streams?

If it matters, I'm running SqueezeCenter 7.3.4 on a Mac Mini with Snow Leopard.

seanadams
2009-09-27, 17:38
so that even if I'm backing up my thesis data to my school server, my music doesn't constantly pause to rebuffer if I'm listening to Pandora or other streaming radio

Is that actually happening?

Streaming audio only uses port 9000 when playing from Squeezecenter so there's no point enabling it in your router since that traffic doesn't traverse your WAN. Internet radio can be on any port as dictated by the station's URL.

You might be better off just putting a hard limit on your bulk transfers. Depends on the Netgear's capabilities - I'm not familiar with it unfortunately.

craigim
2009-09-27, 18:21
Actually, it was happening while I was entering that post. I was listening to Pandora, synchronizing (both downloading and uploading) a large directory, and downloading a batch of podcasts (obviously trying to do too much at once). Furthermore, the activities were taking place on two different computers, so they were both demanding bandwidth and Pandora couldn't keep up. It was pausing to rebuffer every 45 seconds or so.

How do I find out what port Pandora is coming in on? If I'm streaming a radio station and the port isn't specified, does that mean it's coming in on port 80?

seanadams
2009-09-27, 21:18
Actually, it was happening while I was entering that post. I was listening to Pandora, synchronizing (both downloading and uploading) a large directory, and downloading a batch of podcasts (obviously trying to do too much at once). Furthermore, the activities were taking place on two different computers, so they were both demanding bandwidth and Pandora couldn't keep up. It was pausing to rebuffer every 45 seconds or so.

It would help to know if your problem is on the downstream or the upstream side. You probably already know this but streaming radio requires not only a continuous (usually 128K - small for a broadband link) amount of download bandwidth, but also a reliable upstream in order for packet acknowledgements to get back to the source. If you are triggering packet-shaping on your ISP's side, they may be punishing all your sessions in a ham-fisted way as you approach your limit.

Also, what protocol are you using to sync? If it is opening multiple TCP connections then that is "unfair" to other sessions sharing the same pipe, so you may want to see if there's an option to limit the number of connections it uses. That would be getting more to the root of the problem, and if it works would be better than throttling.

Normally TCP behaves well in situations like this. For example if you have a 1Mbps link then you should be able to have six or seven other bulk downloads going simultaneously before your radio is affected. However if you have extremely limited upload bandwidth then that could be a harder problem to deal with.


How do I find out what port Pandora is coming in on? If I'm streaming a radio station and the port isn't specified, does that mean it's coming in on port 80?

I think so. The only problem there is differentiating pandora traffic from other HTTP bulk traffic which would be low priority. Can you do it by LAN-side IP address?

craigim
2009-09-28, 23:38
I actually did not know about the upstream requirement. I've got cable internet from Time-Warner, and I've got something like 368k download bandwidth and 128k upload bandwidth. For the synching, I'm using sftp. For downloading the podcasts, I was using http, so if Pandora is streaming on that port, you're right, there is probably nothing I can do to prefer one data stream over another, and I'll just have to be patient and not try to exchange so much data at one time. As we all know, the internet isn't a truck. It's a series of tubes.