200Mb/s powerline Ethernet kit
Review Despite an early charge, powerline networking has suffered something of a stall over the past few years. The stuff is still shifting off the shelves, but we haven't seen much in the way of improvements in the technology.
D-Link's DHP-303: no change over the years but the model number?
Back in 2007, we were graced with 200Mb/s adaptors that provided a more reliable alternative to wireless when streaming HD video. Since then very little has changed and there's still no sign of the 400Mb/s adaptors that the rival HomePlug and UPA groups have been shouting about the past year or so.
So when we heard D-Link had some new adaptors for us, we had our fingers crossed in the hope they would be the first to sport a 400Mb/s chip. Sadly, they don't. Instead, the DHP-303 units are very similar - both visually and on paper - to D-Link's DHP-300 adaptors from a couple of years back.
Before we go any further, it's best to clear up D-Link's somewhat bizarre naming convention. In what can only be seen as an effort to confuse, it calls the starter kit - as reviewed here - the DHP-303, although the individual adaptors are known as DHP-302s.
The adaptors subscribe to the UPA specification and therefore won't play ball with any HomePlug kit you may already have. They use the latest Aitana chipset from DS2 to fire data over the mains, which is backwards compatible with older 200Mb/s UPA adapters.
Change the settings in software
There's nothing fancy about the design. A black ring houses four status LEDs, while a 10/100Mb/s Ethernet port - there's no need for Gigabit since they won't get anywhere near 200Mb/s in the real world - is found on the underside.
Which frequencies and mode were you listening to in your tests?
The Comtrend PLT junk are UPA. UPA are on-air 24/7 even when they have no data to transfer. Remember - One DS2 equipped piece of UPA junk is just as bad as the another. You can spray a turd a myriad of colours, but it's still a turd and still stinks. HPA are junk, but at least they only poll each other when not transferring data. They still make a racket when transferring.
Did you know that there were bleats on the BT support pages from PLT users who were having problems with their 27MHz keyboards and mice being interfered with by their Comtrend UPA junk? No?
Regarding testing - I have had very scientific tests done in a real UKAS accredited test lab and UPA products fail conducted emissions specs that they claim compliance to by a massive margin; approximately 30dB or 1000x over most spectrum to 30MHz.
If you are on ADSL, also do a quick check and see if there is any difference in line speed with or without your PLT's running.
BT seems to be quite keen on interfering with itself.
Also have a look at: http://www.theregister.co.uk/2009/01/15/bt_vision_interference/
The article was not on BT Vision boxes, but BT knowingly supplying Comtrend PLAs which have failed every EMC test going. It does not matter if you purchase UPA or HPA devices, they all fail BS EN:55022:1998 and spew crap all over the HF radio spectrum.
Everyone from Radio Amateurs to CB users to the military and aviation are suffering from the interference caused by PLA devices and Ofcom's stance sends a clear message to all radio operators - do what you like, we don't care! So I'm sure you'll be saying "haa-haa" when a local CB user running 500 Watts of illegal power causes all of the electronics in your house to go nuts!
Do yourselves a favour - fit UTP wiring and a Gigabit switch. It will be less hassle, less power and you'll not incur the ire of the HF radio users!
Sorry, I didn't mean to suggest that the D-Link device generated similar EM pollution to the BT/Comtrend devices, only that a measure of EM pollution levels could be included as part of the review of these devices.
<-- Obviously I'm in love with myself to be responding to my own comment!