Many interconnect vendors are using Java for building network management applications that can be accessed through Web browsers. Through hypertext-linked home pages set up by the vendor, network managers can use their Java-enabled Web browsers to launch various network management applications. Routers, switches, hubs, multiplexers, CSU/DSUs—virtually any network device—can be configured, monitored, and troubleshooted in real-time from any location. Applications that provide trend analysis and network reports, access to the vendor's technical support, and on-line documentation are also integrated through the Web browser so that configuration changes and network planning can be accomplished using real data instead of guesswork.
One such network management framework—NetDirector@Web from Newbridge Networks—integrates core services such as discovery, topology, and event management offered by open platforms, such as HP OpenView and IBM NetView, and provides distributed network directory services that can be exploited by applications for policy-based management. Specific Web-based applications are bundled with NetDirector, Newbridge Networks' enterprise management solution that integrates with HP OpenView on Solaris, HP-UX, and Windows NT platforms. The NetDirector Home Page provides a directory for the network, hyperlinking all of the company's VIVID family devices to simplify network navigation. The home page reflects the status of all discovered VIVID devices to show, at a glance, the health of the devices and other useful information such as firmware version and events. The network manager can manage the network from home or on the road by hot linking to the devices. The home page also provides a method for the administrator to specify management policies, such as upgrading firmware and software across multiple devices throughout the network, or defining network behavior in the event of a broadcast storm.
Because of Java's real-time capabilities, changes in the network status are reflected immediately, without requiring the network manager to reload Web pages. In addition, Java applets are loaded dynamically from NetDirector@Web servers so that the user does not have to pre-install or continually update the network management software on the system being used to manage the network.
Among the Java-based applications that run under the NetDirector@Web framework is VitalStat, a network diagnostic and analysis tool. VitalStat analyzes baseline response times and other performance characteristics. When deviations are detected, VitalStat diagnoses the problem, attempts to isolate whether the cause is application, server, or network related, and recommends or initiates appropriate corrective actions. VitalStat has a Java-powered Web interface and provides anytime, anywhere management access via a standard Web browser. VitalStat uses intelligent agents that run in the network elements. As a result, it can follow the same path an end-user station uses to access a server in order to detect and diagnose problems. This enables more accurate problem determination for intelligent reporting back to the network administrator. While policies can be configured centrally and reports viewed from the VitalStat graphical user interface, the actual event detection, analysis and response can be addressed seamlessly by the agents themselves without requiring user intervention. Figures 1 to 4 illustrate some of the reports available.
Figure 1: Vital Stat shows the number of errors for selected servers at each node by time in minutes after the event.
Figure 2: VitalStat shows percent utilization for selected servers at each node. This information can be used for performance baselining.
Figure 3: VitalStat uses SNMP's RMON standard to identify a server's top talkers by MAC address in terms of kilobytes sent.
Figure 4: VitalStat identifies how the traffic of a selected server is distributed by protocol. Among the protocols identified are IP, IPX, TCP, and UDP.
NetDirector@Web uses several levels of security to control access to the network. The first level of security is a firewall. As NetDirector@Web is targeted for management of an intranet within a firewall, the firewall prevents unauthorized users outside the intranet from accessing the network.
In addition, administrators can define a list of allowed users/hosts that have access to various management functions. This type of security provides greater control than offered by SNMP community strings. Telnet, FTP, and Web connections are secured through host access security and by user name and password authentication. Only the "root" user with a valid password is given access to certain administrative functions. Java provides still another level of security: it limits the operating system and resources that the application can access. Java also has virus protection to prevent viruses from attaching themselves to the applications.
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