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The MGW 2400 allows three types of users: guests, administrators and a supervisor. Guests can view channel parameters and user profiles. Administrators can create, edit and delete channels as well as start and stop them. A supervisor determines those rights plus he or she can create, edit and delete users. Only a supervisor can restart the MGW 2400 without power-cycling the device.

I tested the MGW 2400 by connecting it to a Windows 2000 PC over an RS-232 serial cable. Using HyperTerminal, I logged in with the default user name and password and was presented with a menu-driven interface that asked for host name, network settings and user authentication. I could also invoke FTP to send software upgrades and configure shared access to media clips using a preformatted external SCSI disk. Once the network is set up, the same command menu is available via telnet but not SSH.

The unit comes with two 10/100-Mbps NICs--one for streaming services, one for management. The NICs must be assigned to different networks; if they're assigned to the same network, the host name of the device will be associated with both NICs, and the device will be unreachable.

I set up streaming services on one network interface and dedicated the other for management using MGW 2400's management console, the Element Management System (EMS). The EMS runs on a separate PC and requires a Pentium III with Windows NT 4 or Windows 2000 Pro and 128 MB of RAM. The only information required is the IP address of the MGW 2400; however, if you don't input the device's IP address, the EMS will search the local subnet for devices to manage.

The EMS console provides a display of the installed MGE-400 or MGE-400D modules. I connected a Marantz DVD player (DV4100) to the MGW 2400 using a stereo minijack audio cable and a video BNC cable. The display showed that the MGE-400D was connected to the DVD player and automatically detected the Composite video source.The MGE-400D module set a default 44.1-KHz sample rate for audio signaling and provided a maximum 2-Mbps encoding rate, which supports resolutions from 160x112 to 384x288. A wizard took me through the process of creating a channel for distribution, letting me choose an installed encoding module and identify the target stream as unicast, multicast or both. Although unicast channels are limited to 10 simultaneous users, you can set the channel to distribute a multicast stream from the device or from an external Windows Media Server (WMS). The MGW 2400 supports a maximum of four external servers with no configuration necessary. As soon as you export a unicast or multicast stream from the MGW 2400 to your WMS, a unicast publishing point or multicast station is automatically configured.

I set up a channel to distribute a DVD of Blade Runner using both unicast and multicast streams to PCs with Windows Media Player 7.1 and Mercury Interactive's LoadRunner 7.5.1, a testing device that generates multiple, simultaneous media requests from the streaming server. From a unicast point on the MGW 2400, a 2-Mbps bit-rate stream sent a DVD-quality view of Los Angeles in 2019 to 10 users. The same quality was available to unlimited users from a multicast station set up on a WMS.

If you're streaming over a low-bandwidth connection to a remote site, you can adjust the bit rate dynamically to relieve network congestion as demand increases. I tested this using LoadRunner's Media Player clients to increase the number of multicast users to 100, which caused video delay from network congestion. Rather than reduce the client requests, I adjusted the bit rate to 750 Kbps and then 350 on the fly. Within seconds, video delay was reduced and the test network was decongested.

You can configure the encoding rate from 64 Kbps to 2 Mbps as necessary. Being able to adjust the bit rate adds value to the MGW 2400: If you find that a live event is hampering your other mission-critical applications or flooding a pipe to a remote office, you can reduce the bit rate accordingly.

Sean Doherty is a technology editor and lawyer based at our Syracuse University Real-World Labs®. Write to him at [email protected].