Salvatore Salamone
When it comes to providing bandwidth for applications like multimedia and video over LANs, ATM (Asynchronous Transfer Mode) gets all the attention. Somewhat overshadowed by ATM products, although now starting to get the respect they deserve, are Ethernet switching hubs. These let a company ease network bottlenecks and save money by not having to upgrade workstation adapter cards or installed network cabling.
Al Herrington, the communications manager at St. Jude Children's Research Hospital and a beta user of the ONcore Switching System from Chipcom (Southborough, MA), says the switching hub integrates easily into his network, "and the learning curve is almost zero." Because virtually all major hub vendors offer upgrades to ATM via modules that you plug into a hub, today's Ethernet s
witching hubs offer a stepping-stone to ATM.
In the past nine months, many leading router and hub vendors that lacked switching technology have acquired companies that have it. Cisco Systems (Menlo Park, CA) acquired switching-hub vendor Crescendo Communications, Network Systems (Minneapolis) acquired Bytex, 3Com (Santa Clara, CA) acquired Synernetics, and Chipcom merged with switching-hub vendor Artel Communications.
Cisco recently introduced its Catalyst switching hub, the first product from its relationship with Crescendo. Optical Data Systems (Dallas, TX) and Kalpana (Sunnyvale, CA) have partnered to integrate Kal-pana's EtherSwitch technology with ODS's Infinity intelligent switching hub.
Traditional hub vendors such as Cabletron Systems (Rochester, NH) and Santa Clarabased Synoptics Communications are also releasing products. Cabletron scheduled a May release for its Multi Media Access Center-Plus, a fault-tolerant switching system that incorporates ATM and delivers aggregate bandwi
dth exceeding 10 Gbps, providing 500 ports of connectivity and 160 LAN segments. Cabletron's ESX-MIM MMAC module already supports the company's switching technology called Secure Fast Packet Switching, which incorporates Ethernet and ATM switching technologies. Similarly, Synoptics' Lattis System 5000 intelligent hub will integrate the company's ATM, Ethernet switching, and ATM/Ethernet translation technologies into one platform over the second half of this year.
Ethernet switching offerings from other hub vendors include the LANswitch family from Lannet (Irvine, CA), which are cards for Lannet's Multinet hub; Kalpana's EtherSwitch EPS-1500; the Powerhub from Alantec (San Jose, CA); the Elite ES/1 from Standard Microsystems (Hauppauge, NY); and the Series 6000 with its PowerSwitch module from Networth (Irving, TX).
Ethernet switching hubs are also coming from start-ups that have expertise in switching or high-speed networking, such as fast Ethernet pioneer Grand Junction (Fremont, CA), whose Fas
tSwitch gives 25 switched 10-Mbps end-user connections and two 100-Mbps fast Ethernet server connections. Other products are the EIFO Client/Server Switching Hub from FDDI (Fiber Distributed Data Interface) specialist Network Peripherals (San Jose), the SH 516 from NBase Switch Communications (Chatsworth, CA), and WaveSwitch from Plaintree Systems (Wellesley, MA). The SH 516 and WaveSwitch connect multiple Ethernet segments to fast Ethernet networks.
Hub capabilities vary widely (see the chart). The EIFO product sells for about $8000, while Cabletron's switching modules alone can cost $8000 or more each, with hubs selling from $12,000 to $50,000. However, enterprise hubs usually support a higher number of LAN segments per switching module and workstations per segment than workgroup hubs do. Thus, enterprise hubs typically offer greater flexibility and management functions at costs of about $300 to $400 per port over a typical workgroup hub. One way to separate hubs is by the size of the network they wi
ll service and the functions they support.
Table: What to Look For in Hubs (This table is not available electronically. Please see June, 1994, issue.)
Switching Hubs Get Their Due
