|TRENDnet TPL-303E2K 200Mbps Powerline Adapter|
|Reviews - Featured Reviews: Network|
|Written by Colin Armstrong - Edited by Olin Coles|
|Sunday, 15 August 2010|
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NAS Testing Process
A small-but-important note before I begin: In an ideal environment, the power should be as balanced and unused as possible. This means the power outlets the adapters reside on must be unused. Going into the tests I wasn't aware of this; I had one adapter plugged into an outlet on the wall which was already powering a variety of other components (some including a router, modem, printer, computer, and monitor.) Running the tests, I was able to achieve speeds of 4.4 MB/S, which is well under the advertised 200 Mbps speeds. Shocked, I simply moved the adapter to a different, unused outlet, and the speeds nearly doubled. So, the current power being used and the empty power outlets play a huge role in determining the speeds, which means these tests may or may not be duplicated.
Another thing to note is the advertised 200Mbps is the theoretical rates. Realistically, the actual throughput should be something like 100Mbps, but in a real-world scenario, taking the electrical wiring into consideration, you should expect a 60 to 70Mbps speed.
It is also reccommended that you run both adapters on the same fuse line, or ring. In North America, the common electrical wiring situation seems to be "split-phase electric power" , which is essentially two separate power lines. By plugging in both adapters to outlets on different lines, you should expect to see speeds of roughly 10-30Mbps.
In case you're not up to speed with network terminology, our you're just new to the technology, here is a little refresher for you. The basic unit data measurement is called a bit (one single binary digit). Computers use these bits, which are composed of ones and zeros, to communicate their contents. All files are stored as binary files, and translated into working files by the Operating System. This two number system is called a "binary number system". In comparison, the decimal number system has ten unique digits consisting of zero through nine.
Have you ever wondered why your 500GB hard drive only has about 488GB once it has been formatted? Most data files use the binary number system to express file size, however the prefixes for the multiples are based on the metric system. The nearest binary number to the metric amount of 1,000 is 1,024; which means that 1,024 bytes is named a Kilobyte. So even though a metric "Kilo" equals 1,000, a binary "Kilo" equals 1,024. Are you confused yet? Don't be surprised, because even the most tech savvy people often mistake the two. Plainly put, the Kilobyte is expressed as 1000 bytes, but it is really comprised of 1,024 bytes.
Most network engineers (myself included) are not fully aware that the IEC changed the way we calculate and name data chunks when they published the new International Standards back in December 1998. The International Electrotechnical Commission (IEC) removed the old metric prefixes for multiples in binary code with new prefixes for binary multiples made up of only the first two letters of the metric prefixes and adding the first two letters of the word "binary". For example, instead of Megabyte (MB) or Gigabyte (GB), the new terms would be mebibyte (MiB) or gibibyte (GiB). While this is the new official IEC International Standard, it has not been widely adopted yet because it is either still unknown by institutions or not commonly used.
Personally, I think the IEC took a confusing situation and simply made it more of a mess. As I mentioned earlier, the Kilobyte was previously expressed as 1000 bytes, even though it was really comprised of 1,024 bytes. Now, the Kilobyte really is expressed correctly as 1000 bytes, and the Kibibyte is the item comprised of 1,024 bytes. In essence, the IEC just created a new name for the binary item and left the existing name for the metric item. Hopefully that clears things up, and you can thank Benchmark Reviews for training the next generation of Network Engineers.
Since this is the first Powerline Adapter we've reviewed, I'm going to do my best to be as detailed as possible in every instance. Within these results, both 1GB and 10GB files were tested for transfer speed. The various tests were run three times each, and the average was recorded. The tests were run by copying the file from a computer connected directly to the router via ethernet to my desktop, which is connected to the powerline adapter. Also, a wireless transfer was done just for comparison. Both 1GB and 10GB files were tested across two computers connected via:
Test System Hardware