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Siemens SpeedStream 2501 power-line USB adapter review: Siemens SpeedStream 2501 power-line USB adapter

Siemens SpeedStream 2501 power-line USB adapter

Brian Nadel
4 min read
Siemens SpeedStream 2501
With its ability to transform any 110V AC outlet into a networking port, power-line networking is perfect for those who don't want to haggle with complex cables or problems with wireless interference. The Siemens SpeedStream 2501 power-line USB adapter makes a virtue of simplicity, with one of the quickest and easiest setups of any networking product, but it lacks the speed of other adapters. It's a good choice if you don't have an available Ethernet port on your PC and you need to connect via USB. At between $50 and $75, the SpeedStream 2501 is a bargain with comparable equipment from Linksys and Netgear selling for $15 more. For those who can put up with its sluggish performance and the lack of a true manual, the simplicity of Siemens's SpeedStream 2501 makes the connection.
Admirably tiny and light, the SpeedStream 2501 is no bigger than a typical small AC adapter for a cell phone, extends only 1.5 inches below the outlet, and is about half the size of the SpeedStream 2502 Ethernet adapter. Still, Siemens finds room for three LEDs, which show network activity, link status, and packet collisions, all of which can come in handy when monitoring or troubleshooting your network. Installing the adapter is a two-minute affair. Just run the installation wizard on the included CD-ROM, which installs the drivers and configures your computer; plug the adapter into the wall; and connect it to the computer's USB port. All you have to do is enter a power-line network name. When you're finished, the SpeedStream configuration utility adds an icon to your desktop.
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The SpeedStream 2501's configuration utility displays connected adapters.

The software's tabbed interface includes sections named Device (to show status, link quality, and all accessible networks), Network (for MAC address and data rate), Security (which lets you update the password from the default SpeedStream setting) and Advanced (for remotely changing the password of other HomePlug devices). With 56-bit DES encryption built in, data travels securely over power lines. Unlike the company's wireless products, unfortunately, the SpeedStream 2501's software lacks a task tray icon to show signal strength and link status at a glance.
Because it's based on the HomePlug 1.0 standard, the SpeedStream 2501 can work with other power-line devices, although you may need to change the password on the power-line adapter to get it to work with other HomePlug devices. The SpeedStream 2501 can run on any PC with Windows 98 or a newer operating system and an unused USB port. Unfortunately, it lacks drivers for Macintosh computers. While this adapter can pass data to a print server without fault, the device doesn't include a USB cable, and we experienced erratic performance with it connected through a Belkin four-port USB hub.
Chariot throughput tests  (Longer bars indicate better performance)
Throughput in Mbps  
WPC55AG 802.11a
WPC55AG 802.11g
Siemens Powerline Ethernet adapter
Linksys PLUSB10 version 2
Siemens Powerline Access Point
Netgear XE102
Siemens SpeedStream 2501
As its benchmark, CNET Labs uses NetIQ's Chariot 4.3 software on a console system with clients running NetIQ's Performance End Points 4.4. Our throughput tests measure the transfer speed of a file that a user might send across the network. This is known as the payload throughput and does not include packet errors and other data that might be transferred over a network. Payload throughput can vary widely from the bandwidth speeds vendors advertise and is a much better gauge of what you're likely to experience with a standard file transfer. For more details on how we test networking devices, see the CNET Labs' site.
The SpeedStream 2501 disappoints on speed and range. The 3.3Mbps of throughput it provides is well behind the pace set by Siemens's Powerline Ethernet adapter and one-third slower than that of Netgear's XE602 power-line adapter or Linksys's PLUSB10 version 2. It is, however, able to distribute full-screen video while listening to an Internet radio channel and moving data back and forth; so unless you're a power user, you probably won't notice the difference.
The SpeedStream 2501's range has a lot to do with how your home or office is wired. Outlets on the same circuit breaker or fuse provide excellent connections. Unfortunately, those on separate circuits prove to be unreliable because the signal needs to travel from the outlet to the fuse box, then on to its destination. In our office setting, the adapter worked well with clients extending to about 150 feet, but in our home setting, it performed inconsistently with outlets in adjacent rooms or those separated by a floor--sometimes dropping the connection entirely.
Siemens covers the SpeedStream 2501 for two years and provides help on its Web site, with downloads for the six-page setup guide, setup software, installation tips, and warranty information. Unfortunately, the setup guide itself provides only basic installation instructions and the lack of a manual means that you won't get full documentation, specifications, troubleshooting help, information about encryption and security, or details on network setup and optimization, not even online. The company has technicians available via phone or e-mail 24/7, but we wish Siemens included better documentation with the unit itself.