In a recent post on “How to Build an 100000 port switch” which is a paper from a US University on some nice (but mis-guided) research by students. Ignoring the content of the paper because it isn’t particularly relevant to real life there is a classic line hhedeshian
Lets see… That’s 100,000 ports with 2 LEDs each (link, action/fdx/speed/poe) for a total of 200,000 LEDs. Lets say they use some of the cheapest SMD LEDs on the market. Well use digikey part number 160-1183-1-ND which is a cheap 0603 foot print green LED. At quantity 200,000 that comes out to $12,000 in cut-tape packaging or $9,450 if you buy 210,000 of them in 3,000-qty reels.
Lets say that all of the link LEDs are on 100% of the time and the the activity LED is on 50% of the time. That gives us 150,000 LEDs on at any given point in time. Our example LEDs use 20ma at 2.1V. So 150,000 LEDs at 20ma uses 3Ka. In total, 6.1Kw is burned by the green LEDs.
All that blinking… Damn. I want one NOW!!! More than a girl friend!
Brilliant, awesome piece of geek indirection with facts. All most people can see is the 100000 ethernet ports and Layer 2 broadcast domains. But I’m with hhedeshian, I want to see that many lights!
Postscript
Why do universities insist on publishing in two-column format ? Its a right pain to read on a computer.
