<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: Arial; font-size: 12pt; color: #000000'>----- Original Message -----<br>From: "Martin" <asterisklist@callthem.info><br>To: "Asterisk Users Mailing List - Non-Commercial Discussion" <asterisk-users@lists.digium.com><br>Sent: Wednesday, September 23, 2009 11:01:04 AM GMT -05:00 US/Canada Eastern<br>Subject: Re: [asterisk-users] Asterisk on a Beagleboard?<br><br>Even PCI has 133MB/s ... so what ? Also isn't USB only target ? It<br>doesn't do DMA ...<br>so it might be same as PCI Target chips that slow down the CPU<br><br>TDMoE has to have those frames on time all the time forever ...<br>these ethernet frames are sent both ways every 1ms<br>that might be (or not) too much load on the small CPU<br><br>loose a few frames or deliver late and your voice TDMoE won't work right<br><br>I just speculate here<br><br>Martin<br><br>On Wed, Sep 23, 2009 at 7:56 AM, Jeff LaCoursiere <jeff@jeff.net> wrote:<br>><br>> On Wed, 23 Sep 2009, Tzafrir Cohen wrote:<br>><br>>> On Tue, Sep 22, 2009 at 07:43:51PM -0500, Martin wrote:<br>>>> I do not know if fonebridge would work here since it sends/receives<br>>>> the ~2 Mbps (for each circuit/port)<br>>>> of data over ethernet ... constantly. That could choke the USB ...<br>>><br>>> Ethernet has frames. While I'm not exactly sure how ethernet over USB<br>>> works and how TDM over Ethernet (MF) works, I would speculate that it is<br>>> far from flooding the USB bus.<br>>><br>><br>> Even USB 1.1 was 12Mbps. Should be plenty of room for a mere 24 channels<br>> of ulaw :)<br>><br>> j<br><br>The test we did was actually with 2x T1s worth of calls (48 uLaw calls) on the Beagleboard using the Dual port fonebridge.<br>
I'm not suggesting this would be a good production quality system. I
think a native Ethernet connection and not via a USB adapter would be
more efficient but the CPU was able to handle the call volume no
problem.<br><br></div></body></html>