Truly Wireless Networking
Strix Access/One's unique configuration can put an end to cabled networks.
It's ironic that you have to worry about laying down cable when you roll out a wireless network, but it's true. In a conventional wireless network, all the wireless nodes are actually cabled to the main network.
Access/One Network (AO) eliminates the need for hard wiring the wireless nodes. It uses wireless technology itself to connect those nodes to the corporate network. The wireless data packets hop from node to node until they reach a gateway to a wired network connection.
AO comes in stackable modules that assemble into a node (see Figure 1). AO supports A, B and G radio band modules. Each node requires an A- or a G-band radio module for node-to-node communication and a second radio module (either A-, B- or G-band) to support user connections. You can also add additional radio modules to the stack to support multiple radio bands.
Although most nodes don't require a wired Ethernet connection, at least one of them must be wired to a backbone network. Also, all nodes still require externally supplied 18-volt power.
For this evaluation, I received three nodes. The first was configured as a network server, the second as a relay node and the third as an edge node. I installed an Ethernet cable between the first node and my router, which simulated a wired network and acted as a DHCP server. The server node controls up to eight relay or edge nodes. The edge node connects users' devices to the network and the relay node simply extends the coverage area of the edge nodes.
The setup software adds an IE plug-in that is compatible with IE 6.0 or later. It also installs mDNSresponder, which searches for attached Strix nodes. You'll have to reboot to complete the setup process.
|Figure 1. Strix System's Access/One modules stack to form a wireless node.
The IE plug-in opens a Manager/One (MO) utility pane on the left side of the browser window and displays the individual wireless modules it has discovered. The MO is the network management and configuration tool for AO (see Figure 2). This is present in each module as a Web server, and you can get to it with most Web browsers. You can use the MO with the network server to simultaneously configure all the modules in a network cloud, instead of manually setting one module at a time.
|Figure 2. The Manage/One network management software lets you configure and manage your Access/One nodes. (Click image to view larger version.)
The MO updates its data periodically, but I would prefer that it refresh at shorter intervals. It takes more than two minutes to correct the display to reflect any changes made to the network topology. On several occasions, the plug in displayed obsolete information for such an extended period that I had to close and restart the browser. The "refresh" command didn't immediately update the network topology data.
The utility pane helps you determine the IP addresses of individual modules and gives you a quick overview of the network topology. You need an IP address to log in to a module, and the plug in is the simplest way to retrieve that. Double-clicking on the network server module icon is the quickest way to open the MO on the network server.
The MO console displays valuable information like node statistics, node stack details and network infrastructure for your entire network, individual modules and network activities. The intuitive mouse-over feature also displays a wealth of information, such as module IP addresses and communication status on individual objects. Online help and a legend describing the icons and the color scheme used on the MO display would have helped here.
Deploying the hardware is simple—just plug the AC adapter into an AC outlet and the hardware installation is done. Configuring the network, however, is much more time consuming. For a network parameter change to take effect, you have to reset all affected nodes. This process takes about three minutes.
Nodes reboot one at a time to reduce network disruption, but data packets will be blocked while the network server resets. Also, after a node is reset, it does a DHCP request and the IP address might change. Therefore, Strix requires that the DHCP server supports IP address persistence to minimize invalid self-configurations and network topology changes. I'd recommend assigning a static IP address to the network server.
Feature Set 20%
1: Virtually inoperable or nonexistent
5: Average, performs adequately
I had trouble determining whether or not certain commands executed successfully, because there is no feedback to indicate if a command was started, in process or done. There are some commands that require a reset, but it isn't obvious which commands require rebooting. I tend to reset modules whenever I change any configuration and refresh the screen frequently to see if that change has registered. Adding or removing a node on the network infrastructure isn't automatically updated on the MO display. I had to press the refresh button repeatedly until it updated the network topology. Due to network latency, it usually took about two minutes.
Can You Hear Me Now?
Roaming lets you move from one node coverage area to another with minimal risk of losing data (but you can lose data if the handoff is not properly handled). Your computer decides when and with which node it will connect. The wireless network nodes must provide fast authentication to allow instant login to the new node. In the event of data loss, it can be difficult to determine which node is at fault if an error occurs sporadically or inconsistently.
I had a few unexpected packet drops when I moved my laptop from one area to another. My laptop briefly lost the network connection then reconnected through the new node. After that brief lapse, it went through a new DHCP cycle. This would be a problem when transferring a file. Since a new network connection starts a new session, it will disrupt file transfer, so
I wouldn't recommend transferring a large file while roaming.
The recommended radio signal range for each node is about 60 feet, with about 30 users per radio. Each network server will serve a maximum of eight nodes. To add more than eight nodes, you'll have to add another network server. You can use the Strix Architect/One program to predict node quantity and locations instead of doing an on-the-ground RF site survey.
Security is a critical requirement for wireless
networks, where the physical security boundary is nonexistent. It needs strong authentication protocols to verify that each user has the proper credentials, as well as a strong encryption protocol to protect transmitted data. AO supports most of the standard authentication and encryption protocols, including MAC address control list and 802.1x EAP (TLS or TTLS) authentication protocols. It also supports Static/Dynamic WEP and Dynamic AES encryption protocols, and RADIUS server support. It will be your job to properly configure AO's security settings.
AO is an ideal solution
for buildings that are
difficult to wire and for deploying temporary
wireless networks. You could also use it as an alternative to wired nodes. I like the simplicity and flexibility of the hardware, although it was disappointing that the configuration process requires resetting a module. This is a good product that needs a bit of fine-tuning
in the configuration and monitoring interface to become a great product.
Yong Cho, CCNE, is an
electrical engineer and has worked on network product design. He has installed,
tested and debugged network hardware.