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Earlier this year analyst firm Gartner questioned the wisdom of running Gigabit Ethernet bandwidth to desktop PCs, arguing that the money would be better spent on improved security, application optimisation and mobility services.
There is no doubt that 1Gbit/s equipment will eventually replace Fast Ethernet in the LAN, and is already doing so in core routing systems. But for now at least, it is rare for organisations to have more than a few desktops or workstations running applications that require Gigabit Ethernet capacity to access or transmit large data files or databases on a regular basis.
For everyone else running nothing more demanding than Microsoft’s Office suite, email and web browsing applications, 100Mbit/s Fast Ethernet links are still generally up to the job. And in most cases they remain significantly cheaper to buy than gigabit equivalents, although the cost differential is steadily narrowing.
Another advantage of deploying Fast Ethernet 10/100 switches at the workgroup or departmental level is that category 5 unshielded twisted pair (Cat 5 UTP) cabling can be re-used from existing installations, whereas Gigabit Ethernet often needs Cat 5e to support 100m transmission distances at 1Gbit/s speeds.
Although Power-over-Ethernet (PoE) support was not a requirement of our grouptest, some of the devices we tested also have PoE “sister” switches that can be stacked alongside to deliver PoE functions. Fast Ethernet switches can supply enough power for 10/100 IP phones on all 48 ports. With newer gigabit devices, this would not be possible.
Gigabit uplinks are provided via small form-factor pluggable (SFP) optical transceivers. The SFP transceivers come in five variations and provide a range of wide area network (WAN), campus and remote site or datacentre connectivity options.
The standard copper 1000Base-T iteration is good for 1Gbit/s data
transmission over 100m, while the short-range 1000Base-SX and the long-range
1000Base-LX optics handle distances from 550m to 10km. Finally there are the
long-haul optics, the 1000Base-LHX and 1000Base-ZX, which are good for 40km and
80km respectively.
For the moment then, anyone fitting out new offices to handle the capacity
demand of everyday applications can still find better value in 10/100 switches
rather than Gigabit Ethernet, and this month’s grouptest will look specifically
at Fast Ethernet devices with Gigabit Ethernet uplink ports.
We originally specified a 48-port switch with support for Layer 3 routing, but found that many vendors only give limited support for Layer 3 at 10/100 speeds.
Eventually, we tested five switches, with some notable vendors missing from the round-up. HP and Nortel delivered gigabit switches that we could not include in the test, Cisco declined to submit a product at all, and Enterasys and Force10 Networks said they could not meet the specification. SMC and Extreme Networks both said they could not ship a product in time for the testing deadline.
See also:
Zycel's 48-port Fast Ethernet switch features redundant power options but limited Layer-3 routing capabilities. 16 Nov 2006
D-Link has packed features into its xStack DES-3852 switch, reflected in its complex web GUI 16 Nov 2006
Though good value for money, Dell’s 3448 offers limited expansion and inter-switch connection options 16 Nov 2006
An excellent Fast Ethernet switch, though its web-based GUI is not expected until December 16 Nov 2006
The 4500 features RIP capabilities, good SFP support, and easy voice/data network set up 16 Nov 2006All Network Infrastructure
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