Network Layer Switching For The Corporate Intranet To manage the SmartSwitch chassis, you need Cabletron's SecureFast VLAN manager. SecureFast is not a full network node manager, and is designed primarily to manage your Cabletron VLANs. However, its easy-to-use interface will make you look like a VLAN pro in just minutes. In fact, the SecureFast VLAN manager provides the only way to configure VLANs on the SmartSwitch line; Cabletron has done away with cumbersome command-line interfaces. The SmartSwitch can create VLANs on a per-port or MAC address basis. When a VLAN is created, the user defines whether it is to be open (the switch will route traffic openly among this VLAN and others in the system), or secure (only an external router can pass traffic into and out of this VLAN). All the VLANs we set up for testing were open. The secure option is provided for users who need routing policy for se curity, a feature not implemented in the SmartSwitch. Broadcast Interception The SmartSwitch has some protocol-based VLAN capabilities, and it will intercept IP and IPX broadcast packets and contain them to only the ports that need to hear the broadcast--a feature Cabletron calls Broadcast Interception. The company has tailored this technology to listen and control the flow of Internet Group Management Protocol (IGMP) multicast traffic. Adding and removing users is simple once the VLAN has been created. To create a port-based VLAN, simply drag the VLAN name onto the associated switch port. If you prefer the VLAN to recognize users by their MAC addresses, drag the associated MAC address onto the VLAN name, and the user is added to the VLAN. Cabletron has solved one of our biggest complaints about VLAN technologies; SecureFast can be set up quickly and is easy to understand. In addition to its extensive VLAN features and routing prowess, the SmartSwitch supports several advanced features, m aking the switch an excellent enterprise solution. Unlike other switches in this review, the SmartSwitch supports a mixed-topology-meshed backbone with failover ca pabilities. With this feature, you can have up to three active, load-balanced connections among switches. If one link fails, other links will pick up the slack. We tested this feature using FDDI and Fast Ethernet connections, and found that failover time during a loaded test was less than 20 seconds. The SmartSwitch also lets you perform call-tapping to any port in your switching cloud. This feature lets you direct any point-to-point conversation to a Remote Monitoring (RMON) probe or sniffer port and troubleshoot connections without leaving the office. The switch supports four groups of RMON. The SmartSwitch is not flawless, however. The technology inside Cabletron's devices is undergoing rapid changes, bringing new features with each release. The current code is beta, but publicly available to Cabletron switch owners. The software we te sted was finely tuned for IP traffic, while IPX features were just coming online. FDDI users should be aware that the current switching software requires you to build your network in a point-to-point manner, rather than in an FDDI ring. Cabletron says it's working to quickly resolve this serious limitation. 3Com Corp. LANplex 2500 The LANplex 2500 is just one piece of 3Com's LANplex switching solution. The LANplex series combines the best features of switching with a strong VLAN subsystem and a powerful routing engine. Don't be fooled by its low profile, however. The LANplex 2500 has plenty of power under the hood, just like its big brother, the LANplex 6000. Unlike the devices from Cabletron and Case Technology, the LANplex is configurable as a full TCP/IP, IPX and AppleTalk router, capable of Routing Information Protocol (RIP) advertising and Internet Control Message Protocol (ICMP) addressable interfaces. The LANplex relies on VLANs to establish switchin g domains. Creating VLANs on the LANplex can be accomplished via 3Com's Transcend Management software or the command-line interface. We used the command-line interface--an easy -to-use hierarchical menu system--to configure 3Com's switch.

Updated January 10, 1997