Individual nodes are managed by double-cl icking on their respective icons on the network map. SNMPc automatically queries the node for its SNMP system information and decides whether to launch Bitview or Hubview, a pair of graphical node management utilities.

If the device is fully supported, Bitview brings up a bit-mapped image of the device. It provides an accurate picture of all interfaces, complete with blinking lights and a diverse menu of SNMP queries in the window frame. Although SNMPc includes MIB support for most manageable devices in our lab, only the SynOptics LattisHub 2813 merited Bitview support. All other devices are managed through a separate application.

Although not as pretty, Hubview provides the same functionality as the Bitvi ew utility. Lacking the bit-mapped picture of the device, it substitutes icons representing each network interface. Without vendor-specific MIB support, Hubview reverted to standard MIB support for leftover devices. For example, our Sun workstations were not directly supported, but Hubview still c reated an icon-based display of all network interfaces and offered pull-down menus for building most common SNMP queries using only standard MIB and MIB2 variables.

Castle Rock performed well in nearly every situation we threw at it, except one. Although the discovery process can burrow easily through a large internetwork, the layout tool simply lacks the intelligence to accurately map anything but small, flat networks. Apparently, Castle Rock's mapping algorithm is not effective at creating hierarchies and identifying a node's home subnet. Laying out a large network can be very messy. It was inconsistent at placing nodes in their appropriate subnets, resulting in partially filled subnets and a large "lost-and-found" map filled with unrelated nodes. No other product tested had this kind of trouble determining wh ere to place network objects.

To give credit where credit is due, SNMPc's autodiscovery tool is powerful. After accidentally leaving the autodiscovery process running one night, we were surprised to see that it not only probed Syracuse University's campus network, but also ventured across our private frame relay link. After mapping the results and cleaning up the consequent spiderweb of nodes and subnets, we were impressed by SNMPc's reach, but disappointed with a less-than-usable map. It had bounced through our San Mateo lab, into our University of Wisconsin lab and mapped most of our Wisconsin lab network! We recommend tightening the reigns on the discovery process, probing one or two subnets at a time and manually creating an inte lligent hierarchy.

Despite its layout problems, SNMPc performed admirably. Castle Rock concentrates more support on management and performance analysis. For instance, this is the only product that provides both RMON support and performance trend analysis without expensive add-ons. It also features the best MIB browser of the lot.

Experienced SNMP junkies will be pleased with the large selection of MIBs and an excellent MIB browser. Not only does SNMPc allow easy navigation up and down the MIB tree, it includes detailed descriptions of every variable. This is especially useful when building custom SNMP polling variables. This powerful feature lets you customize polling parameters for nodes. For instance, an SNMP poll can test whether a particular interface on a router is operational. If not, the poll generates an alarm.

Finally, if scalability and third-party support are serious concerns, Castle Rock has built in a solid upgrade path. Not only does SNMPc work as a standalone application, it also can operate as a plug-in to the Windows version of HP OpenView. This lends Castle Rock's vendor support and management applications to HP's open platform. It's worth buying for its RMON and diverse MIB support alone.