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End-to-End Content Management

The Starter Kit includes Content Commander and edge nodes or servers called MediaMalls, which store and deliver rich media content and static Web pages. The Commander manages content from its point of origin on remote servers called origin servers and distributes that content to the MediaMalls, which are positioned close to end users. The kit also includes the Director, which redirects client requests for live and on-demand streaming media from origin servers to the closest available MediaMall.

InfoLibria representatives brought a Starter Kit with two MediaMalls to our Real-World Labs® at Syracuse University. The kit was preconfigured with the lab's IP schema to manage and direct content on one subnet and deliver it to another.

The Commander, Director and MediaMalls are housed separately on Dell Computer Corp. PowerEdge 1550 machines running Microsoft Windows 2000 Server SP2. Other hardware platforms are supported. The 1550s are 1U appliances that fit into a standard 19-inch rack. The Commander and Director each sport a single 866-MHz processor, 512 MB of RAM and an Adaptec Ultra 160/m PCI SCSI disk subsystem with Seagate Technology drives. The MediaMalls have similar configurations but use 1-GHz processors.

InfoLibria (screen view) Click here to enlarge

InfoLibria also brought a test server running Microsoft Windows 2000 Server with Windows Media Server and Encoder 7 installed. I added a second test server with the same level of service and a Web server running Windows 2000 powered by Apache 1.3.22. This environment streamed two live unicast shows from software encoders and made available a number of on-demand streams through Internet Information Server (IIS) 5.

All origin servers were placed on subnet 128.230. 97.0 with the Commander, Director and a MediaMall. Another MediaMall was set up close to users on subnet 128.230.92.0. Once all the hardware was installed, I logged into the Commander using an ASP (Active Server Page) with IIS and Java 2 Standard Edition 1.3.1_01 run-time environment.

The Commander

The browser-based GUI for the Commander provides its own authentication method. Commander users have admin, view or edit rights. Admin users have full rights to server configurations, content management, administration and job control. View users can only display such information. Edit users can display and change job information. Creating and managing job information is critical to reducing the administrative overhead required to pre-position rich-media content from origin servers to MediaMalls.

Using the provider wizard, I set up a number of jobs to move files from origin servers to MediaMalls and pre-position content for fast and easy client access. The Commander helps transfer files to MediaMalls by grouping MediaMalls together and using standard file types identified by their extensions (.asx, .au, .mp3, .htm, .mov, .ram and so on). You select a name and indicate whether the job includes standard Web objects or media files. Then you select a method to acquire the selected file types from origin servers via mount points on Windows shares for large volumes of files or by spiders that find and retrieve files from an origin Web site.

When the Commander boots, a batch file sets up mount points on remote Windows shares using the Net Use command. With mount points, you can copy entire Web sites with complex scripts and applications and transfer them to MediaEngines on set schedules. A spider finds and retrieves content from Web servers defined by URL, then stores it on the MediaMalls. I set up a spider job for static Web objects and mount points to move media from the two servers running Windows Media Server. I set the jobs to run once every 24 hours, which made it easy to modify or create content and save the files. I then turned my attention to the Director to orchestrate content delivery using redirection.

The Director

The Director runs on a separate server with its own challenge authentication. Live-event management will be merged with the Commander in a future iteration. That means database support will be standardized under Microsoft SQL Server, the redirection function will have its own hardware resources, and the Commander will require more server resources.

The Director maintains information on MediaMall locations by assigning UIDs (user IDs) along with IP addresses. MediaMalls can be bound to respond to certain clients within configurable IP address ranges. They are also defined by their multifunctional services for On-Demand/Multicast, Live WMT (Windows Media Technology), Live Real (RealNetworks) and Live QT (Apple QuickTime) media.

I configured one MediaMall to respond to all network requests from subnet 128.230.92.0 and the other to respond to requests from subnet 128.230.97.0. I also configured each MediaMall to act as a backup to the other for redundancy and failover. I defined their functions to include both On-Demand/Multicast and Live WMT services.

To redirect client requests from origin servers to MediaMalls, the Director uses a specialized URL that replaces the URLs for origin servers on Web pages and redirects client requests to the Director machine. The Director then sends the request to the most appropriate MediaMall for service.

I tested redirection using on-demand requests for Web objects and streams and live unicast streams. The URLs successfully redirected content from origin servers to the appropriate MediaMalls, depending on whether the request came from subnet 128.230.92.0 or 128.230.97.0. When I unplugged one MediaMall from the network, requests failed over to the backup.

InfoLibria supports live multicast shows and unicast channels. It provides scheduling information to run the shows on specified channels at specified dates and times. You also can configure secure access to events using a RADIUS server.

I set up a show using a live unicast channel by first configuring a MediaMall splitting hierarchy, which means MediaMalls are configured to receive live feeds from the origin server or another MediaMall. I configured both MediaMalls to feed from the origin server. Once the splitting hierarchy was set, I created an NWC channel and assigned it to the unicast source broadcast by the software encoders on origin media servers. After assigning NWC a splitting hierarchy, the Director published a URL for the unicast live channel. When clients on subnet 128.230.92.0 and 128.230.97.0 clicked on that URL, they were served the live unicast stream from the MediaMalls on their subnet.

I didn't test live multicasts, but they comprise single-file transmissions from a multicast-enabled network, such as a satellite network. Those transmissions are sent to multiple destinations in the enterprise via multicast or unicast. The main task in configuring multicast shows is to provide the Director with the multicast file generated from your encoder. I also didn't test InfoLibria's digital rights management support for WMT.

Once the network configuration is set and MediaMalls are configured to receive pre-positioned content, you are on your way to delivering rich media close to users. Before you buy, however, you should have rich-media applications and content in hand. Otherwise, you're not likely to get your ROI before the equipment requires an upgrade.