Connecting Remote Warehouses With WAN

Most VARs and systems integrators are familiar with the concept of 'just-in-time' (JIT) manufacturing. Under this manufacturing process, the correct component must be delivered to the appropriate place at an exact time or the whole manufacturing process breaks down. When this happens, heavy fines of as much as $100,000 per hour are levied on the supplier. As a result, suppliers must maintain very tight control over their products.

Maintaining Tight Control Through RFDC
Alternative Distribution Systems, Inc., (ADS), headquartered in Homewood, Illinois, is a warehousing and transportation company involved in the JIT process. The firm picks up coils of steel from steel mills and delivers them to automobile manufacturers 'just-in-time'. ADS is a 500-person company, with annual revenues of about $75 million. The company maintains a fleet of trucks and ten warehouses totaling over 1.3 million square feet. The warehouses are spread throughout the Midwest and the Southeast.

Because of the need for stringent product tracking, every coil has a bar-coded label attached for identification as it is received in one of the company's warehouses. When an ADS customer needs the steel, ADS workers scan the appropriate bar-coded stock with a radio frequency data collection (RFDC) terminal. The information is transmitted to ADS' mainframe computer. This assures that the proper material is correctly loaded and delivered.

In 1994, Jorge Arroyave, manager for corporate systems development at ADS, implemented this RFDC system. This system uses Spectrum One (Symbol Technologies' 900 MHz spread spectrum technology) portable data terminals in the warehouses. These allowed ADS personnel to communicate with the company's mainframe computer as wireless terminals.

System Proved Costly
Although this system was working, several costly leased telephone lines were needed per warehouse for the RF and other data communications. Each leased line cost from $700 to $1000 per month. This drove Arroyave to seek a different network solution. A corporate decision was made to move all ADS data communications to standard wide area network (WAN) technology. This would provide considerable cost savings over the multiple leased lines and would provide much more centralized network management and support.

Examining Solution Options
Unfortunately, the Spectrum One hardware would not operate over this new corporate WAN technology. Fortunately, Dan O'Brien, president of DOTT Computer Systems, a Flint, Michigan-based VAR, was already working with ADS and its existing Spectrum One system. He was challenged to deliver a RFDC system which would operate over the WAN.

One solution was to replace the Spectrum One system with one of the newer 2.4 GHz spread spectrum systems. These new systems, by definition, operate on Ethernet networks. (Ethernet networks are wired local area networks [LANs].) But this was ruled out early, due to ADS' current investment in the older 900 MHz hardware.

An Innovative Approach To The Problem
So DOTT used Connect's new PowerNet network control unit (NCU), which could support Spectrum One over Ethernet networks. This allowed the VAR to provide a better, more cost-effective solution. DOTT was able to preserve ADS' installed base of Spectrum One hardware and still operate the RF network over the corporate WAN. The new RF system configuration eliminated the need for the costly leased telephone lines. It also provided easy network expansion for the future and allowed DOTT to easily provide remote support from its Flint, Michigan headquarters.

The Benefits Realized By ADS
Arroyave reports that the response by ADS' management has been positive. He says that, because an increased number of faster scanners were part of the upgrade, scanning time for warehouse personnel has been reduced by 70%. As a result, productivity has increased.