The anatomy of a network switch: an eight-port, gigabit glitch

January 27, 2014 // By Brian Dipert
I've had a couple of pieces of networking gear fail in recent weeks; I've decided to "turn lemons into lemonade" and dissect them for your (and my) enjoyment and education.

First on the list is TRENDnet's TEG-S8, an eight-port GbE switch which was in production in the latter part of the last decade (in May 2008, for example, it was promotion-priced at $15) but has now been discontinued (here's the associated product support page ). The TEG-S8 was notable not only for its aggressive pricing but also for its performance-boosting jumbo frame support, and it served me well (albeit only periodically ... I'd phase it in and out of service as my residence locations and network topology needs evolved) for many years.

Recently, however, a few remotely accessible LAN clients mysteriously went offline while I was away on a trip. Upon my return, I noticed that all of the TEG-S8's front panel "link" and "activity" LEDs were extinguished (echoing an experience I'd had nine months earlier); only the "power" LED was still illuminated. I power-cycled the switch and it came back to life ... for a few minutes, at least, until the unwanted switch slumber returned. A few more power cycles resulted in the same undesirable end result, at which point I decided it was time to transition to a switch successor.

Removing four underside-accessible Phillips head screws is all it takes to pry apart the TEG-S8's plastic case. At the top of the following photo, you can see the eight metal-shielded Ethernet ports, with the TEG-S8 power plug to their left:

Below them, you'll notice four SOIC-packaged ICs; I thought "DRAM" when I first saw them. A Google search quickly revealed, however, that they're 1000-Base-T LAN transformers (the G4802CG, to be precise, from Dongguan Mentech Optical & Magnetic), one per two ports. Ironically, however, memory represents the TEG-S8's fundamental shortcoming versus successor-generation products from both TRENDnet and other suppliers. The TEG-S8's diminutive 8 kByte buffer could be insufficient when, for example, shuttling packets between GbE and 100 Mbps clients . Take a look at TRENDnet's now-shipping 8-port GbE