Sprites mods – Dumb to managed switch conversion

When I got my new house, one of the things I did besides painting and redecorating
was rip the old cat2 telephone cable out of the walls and replace it by modern
cat5e cabling. I’ve done a spot of network engineering in the past, so I had a fairly
good idea what I would like to have as a network: GBit everywhere, separate vlans
for the adsl modem, wired clients and the wireless accesspoint… But at that moment
I was too busy to actually implement it: the rickety old 100MBit switch plus a few
extra cables had to do for now. After I was done moving, I’d immediately upgrade it
to what I wanted.

You probably know how these things go… It’s been more than a year since I moved
now, and I finally decided it was time to upgrade everything. I bought myself a
managed 8-port GBit switch to be the proverbial spider in the web. I bought myself
another el-cheapo 5-port GBit-switch for my workstation: a TP-link unmanaged
GBit switch with the typenumber TL-SG1005D, which set me back 17 Euros. Buying
an unmanaged one instead of a managed switch saved me EUR60,
and I wouldn’t need the managing capabilities anyway… or so I thought.

Turns out I was wrong. My access-point, which was to reside on a different vlan, had
to be connected to the switch too… but an unmanaged switch can’t really handle vlans.
Basically, I had to send the unmanaged switch back and spend a lot of money on a
managed switch… or did I? On a hunch, I decided to crack open the switch and look
at the internals. Hmm, seemed there was a RTL8366SB GBit switch IC inthere. I managed
to download the datasheet of the RTL8366, and whaddayaknow, it actually contains
all the logic a managed switch has too! Vlan, port mirroring, you name it and
chances are the little critter can do it. It didn’t have an user-interface though;
you have to send the config to it over I2C, as cryptic hexadecimal register
settings…but that’s nothing an AVR can’t fix.

 1 Next »