Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Technology Stocks : The *NEW* Frank Coluccio Technology Forum -- Ignore unavailable to you. Want to Upgrade?

To: axial who wrote (27613)	7/31/2008 4:49:38 PM
From: Frank A. Coluccio	Read Replies (1) \| Respond to of 46821

My unawareness shouldn't be taken to mean anything beyond my own personal ignorance on the matter. There was a lot of interest in getting under Skype's hood, reverse engineering, and the like, a couple of years ago. Due to its proprietary nature, however, many have lost interest in pursuing it further, despite a following of developers who've built applications around it. What I meant was, I wasn't aware of the sort of targeted performance measurements you referred to earlier. But I'm sure they've been taken and published somewhere, but unbeknownst to me. I'll check out what's been going on over in the world of Henning Schulzrinne, who performed the initial analysis on Skype at Columbia University in 2004, and see if he's published anything new on the subject that might be helpful. -- Edit: No guarantees, but this paper written in 2006 (below) appears to have some of the information you're looking for. Let us all know what you happen to find there ;) -- Design and Implementation of 2.4GHz Wireless Skype Phone Shanq-Jang Ruan, Yi -Ruei Lai and Chin-Kun Wen Department of Electronic Engineering National Taiwan University of Science and Technology No.43, Sec.4, Keelung Rd., Taipei, 106, Taiwan, R.O.C. paper.ijcsns.org -- Another afterthought: Actual network performance findings during the period 2004-2007, where, say, 802.11a/b/g was used, may not bee too useful for anyone using Skype today over 802.11n, since the latter affords the user a much higher degree of throughput capability. ------

To: axial who wrote (27613)	7/31/2008 7:20:29 PM
From: ftth	Read Replies (1) \| Respond to of 46821

Hi Jim, here's some data from a report I have: Using a MIPS32-24KEc core in what was at the time (mid 2006) an advanced handset design, a 3-way VoIP call consumes about 130 DMIPS of the processor's available 490 DMIPS at its top speed of 333MHz (90nm process). That would probably be in a midrange handset today, and newer cores are 1 or 2 process generations advanced from there, with the high end varieties capable of over 2000 DMIPS and over 1GHz. As far as power budget, it varies with different classes of mobile devices, but a ball park figure for the processor performing these activities is about 17% of total power consumption, with the display consuming in the mid-20 % area, and the RF front end processing consuming about 30%. So I think the reason VoIP isn't being talked about as a problem is that it doesn't really tax the capabilities of today's handsets, except maybe the low-budget, low-end types. As far as a relation between this and WiMAX, HSPA, etc, the VoIP processing all happens 2 or more layers above the RF processing, as a separable module that you can bolt to any physical layer. So it's independent except for the indirect RF-related factors like interference and power level. Does this all get closer to answering your questions or am I still off on the wrong track?