How to Become a Network Guru
Switches and Hubs
Why Switch? Why Hub?
The short story is that a switch is better because it allows any port to use the complete bandwidth (100BaseT, etc.) of the switch, as opposed to hubs that split the bandwidth across all ports. Switches also better handle different network speeds, so that two higher speed devices (100BaseT, for example) use the higher speed when talking to each other, even if they need to use 10BaseT to talk to slower devices.
Switches used to be significantly more expensive than hubs, but the price difference has dropped considerably in the last couple of years so that you should now be able to pick up a multi-port 10/100BaseT switch for $50 or less. Most home networks probably won’t see a difference in performance between a hub and a switch, because home network use is very sporadic compared to the business world, where connections are constantly in use.
How Much Faster Is 100BaseT (or 1000BaseT) Than 10BaseT?
Although the numbers increasing by a factor of 10 seem to imply performance leaps of 10, that’s not actually the case. Typically, 100BaseT runs four to five times the speed of 10BaseT in a similar network configuration. There are so many factors involved in the typical network that it’s almost impossible to determine how fast it should be running (better to focus on a comparison of before and after).
What’s the WAN Port for on My Hub/Switch?
WAN stands for Wide Area Network and allows the hub to connect to other networks, typically other switches or “upstream” connections. When you use a hardware router to share a high-speed Internet connection (cable, DSL, etc.), you typically connect the high-speed modem to the router’s WAN port.
LocalTalk and G3/G4 Macs
Built into all Mac models from the Plus to the beige G3s and Wallstreet PowerBooks, LocalTalk was the original method of Macintosh networking. Though it was slow (about 20 kilobytes per second), its ubiquitous nature made it the choice for the casual network user until Ethernet prices finally came to Earth in the last couple of years. Since LocalTalk used the Mac serial (printer and modem) ports to communicate, this networking option was abandoned with the debut of color-case Macs in 1998. The beige desktop G3s were the last new model to use LocalTalk, but even they didn’t use it well. You had to download a software update (LocalTalk G3) from the Apple site to fix a multitude of printer and connection problems that cropped up after the initial release.
Although LocalTalk is gone from new Macs, there are still a great number of systems out there that use it, usually because an Ethernet upgrade is either unavailable or prohibitively expensive. LaserWriters are still common in home and business, and many models require LocalTalk connectivity.
The easiest way to connect LocalTalk devices to a Mac without serial ports is to obtain a hardware LocalTalk-to-Ethernet adapter, which translates the network signal in both directions without extra effort on your part. The main difficulty here is adapter availability, as the adapters have become scarce with the passing of LocalTalk from the new computer scene. Your best bet for older hardware are sites like MacResQ or the auctions of eBay. Since the types of adapters varies, get as many details about what you’re buying as possible, to make sure you end up with the right thing.
Software is also an option here, as Apple provides a control panel (and free download) called LocalTalk Bridge that will connect an Ethernet and LocalTalk network. The downside of this is that you need to have a computer capable of connecting to both networks that can act as an intermediary. If you only have an Ethernet Mac, LocalTalk won’t do you any good.
Copyright © 2001 Matthew Glidden,
mglidden@atpm.com.
Also in This Series
- Mac to Windows: Troubleshooting the “No Logon Servers Available” File Sharing Error · October 2004
- Using WEP Security on an AirPort Network · July 2004
- Whatever happened to…Threemacs.com? · September 2003
- Clandestine Wireless Networking and MacStumbler · July 2003
- Learning to Share With Others: Sharing Preferences Overview · April 2003
- Serving Files Using FTP in Mac OS X · December 2002
- Switching Between Networks in Mac OS X · November 2002
- The Audio/Video Quadras (660av, 840av) · September 2002
- Thoughts on Apple’s Xserve · July 2002
- Complete Archive
Reader Comments (20)
This site was the first hit in a Google search for "hubs and switches."
cl
Category 6 cables are comprised of 4 unshielded OR shielded twisted pairs of wire that reliably transmit data at up to 250 MHz. CAT 6 cables meet ISO 11801 Class E specifications. These cables also meet the capacitance, resistance, and impedance tests required to get Category 5e certification (used with gigabit Ethernet).
The proposed Category 7 specifications are for cables comprised of 4 shielded twisted wire pairs that meet ISO 11801 Class F specifications for data transmission at 600 MHz.
Can anyone tell me about the various types of switches, like L1, L3, etc., and how they work?
"Uhm...then don't do that."
The Cube doesn't have a Gigabit card in it, and there's an article (written four years ago!) that makes it seem like Cat6 is basically pointless with most consumer gear right now.
In reality, a switch is a hub. More accurately, it's a hub on steroids. The purpose of both devices is to allow multiple devices to communicate together via ethernet connections and/or allow an incoming network (i.e. internet) connection to be shared among all the attached devices.
The problem with a nonswitched hub is that all traffic gets sent to every single attached device. This results in data "colliding" with each other and significantly reduced performance.
A switched hub solves this problem by having technology to deliver packets of data only to the device it was intended for. Since this is the ideal scenario anyway, you'll see why there's really no reason to use/buy/sell a legacy hub.
And, for what it's worth, pretty much any broadband router that has multiple jacks for connecting computers has a switched hub built in.
Thanks for your note. Some old Mac OS versions (System 7, I think) allowed you to choose either the modem or printer port for LocalTalk. Sounds like they eventually (wisely) limited it to printer-only. You could probably have counted the people who picked "modem" on one hand!
Matthew
I have an industrial system with data logins - 2 slave nodes and master (which is an HMI screen). Each one has 1 Ether port and I want to connect all this mess to internet to display data on desk PC. Do I need switch only (3 in and 1 out)or router, or router only (3 in 1 out), or switch 3 in 1 out and 1 in 1 out router (with firewall...).
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