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Null Modems and Networking for Computer Hobbyists

A null modem is a specially designed cable that allows a user to connect two computers directly to each other via their communications ports (RS-232 ports). A null modem cable was used in the past to connect two DTE (Data Terminal Equipment) devices. Normally, you connect DTEs to DCE (Data Communications Equipment) devices- a PC to a modem or printer, for example. Before network cards and crossover CAT5 cables, this was the easiest way to connect two PC's together- serial port to serial port.

Null Modems In Networking Today

These days, null modems are particularly useful with portable computers because they enable the computer to exchange data with a larger system.  For example, with the Belkin Direct Cable Connection, you can instantly share files, folders, printers, Zip drives, or you can link two PCs for head-to-head gameplay. Just connect two computers with DB25 female parallel ports to share information.

Advantages

  • Extremely efficient data transfer
  • Total compatibility with all devices every time.
  • Flexibility.
  • Quick and easy installation.
  • Requires only Windows® 95, 98 and 2000 drivers.

Computer Hobbyists and Rolling Your Own Null Modems

Then there are “roll your own null modem” gizmos to satisfy the geek in all of us. For example, PAWGO Null Modem Adapters combined with a null modem cable make the world’s smallest sync solution for your laptop or a network away from your cradle. You can attach your cell phone’s data cable to your Palm Pilot hand-held for an easy, fully-enabled connection to the Internet.  It comes in handy if your brand of phone doesn’t make dedicated palm cables. One 9-pin cable can be used for many uses: wireless laptop, PC/Laptop to phone, GPS units, printers, network connections and dial up modems.

Null Modems Used as Syncing Solutions Between Laptops and Palm Pilots

Or, if you have a Palm III, you can just buy a Palm V Modem and then send and receive data at your convenience. You don’t have to connect your Palm V connected organizer directly to your computer or laptop to update your data.

With your modem and organizer you can:

  • Synchronize your organizer and Palm™ Desktop organizer software from remote locations with one touch.
  • Take full advantage of Palm V organizer applications, such as mail, using Network HotSync and TCP/IP.

The null modem is a way for those of us that missed the time of do-it-yourself computer hobby kits and garage-based startups to relive the excitement of those golden days of discovery and innovation. The null modem: a useful blast from the past.