An ounce Of prevention ...

A large international manufacturer of semiconductor parts saves critical network connectivity during AT&T's global frame relay outage.

Michael L. Keenan, Senior Editor

On April 13 - that was a Monday, not a Friday, for you superstitious readers - the world went dead for 6,600

When AT&T's Stratacom frame relay nodes overloaded circuits and brought down the network, the effect was quite sobering. People who had put 'backup' on the back burner suddenly took interest.

General Semiconductor (GS), an international manufacturer of rectifiers, voltage suppressors, signal transistors, and diodes, was one company that survived the incident in good shape thanks to an ISDN backup system.

GS has an impressive record of meeting tough 'just-in-time' schedules at a part-per-billion defect level - and it still has that record, despite the AT&T outage. GS, with a committed frame relay information rate of 32 Kbps for each of its three private virtual circuits (PVC), didn't miss a beat as its ISDN backup system took over international data communications.

Frame relay service for this Melville, Long Island-headquartered company went down at around 2:30 in the afternoon and was not available again until 10:30 the same evening. GS's window of activity covers almost a full 24-hour day, with network nodes spanning most of the world's time zones. It has manufacturing plants, warehouses, and sales offices in the U.S, Europe, and Asia, and keeping a data/communications network open just about 24 hours a day is critical to the company's operation. Even a moment of downtime could be very costly in lost revenues and productivity.

'The mission-critical aspects of the company are based on an AS400 midrange environment that is spread amongst various locations throughout the company,' says Joe Gagnon, communications manager for General Semiconductor. 'We essentially have a star topology with Melville as the corporate headquarters and processing center for the support of remote midrange communications.

'We also have a pretty substantial private voice network because phone charges for communications throughout the various GS facilities would be quite expensive on the public phone network,' Gagnon says.

THREE NETWORKS IN ONE

GS has three dissimilar forms of communications: 1. Traditional IBM SNA activity that is primarily host to host, 2. LAN-based requirements, 3. Private voice network. Those various forms of activity are deployed over the wide area depending on the type of location to which it is being connected.

The warehouses' need to receive and ship products is a midrange systems function. Those locations are only provided with an SNA control unit for access to the midrange system.

Each sales office has a small LAN that uses terminal sessions to access the midrange system. These networks provide e-mail and application-sharing activity to the various file servers throughout the LAN.

The manufacturing locations have more diverse requirements. They use AS400 host-to-host connectivity and LAN-to-LAN connectivity. They also have PBX-to-PBX connections for the private voice network linking the center in Melville to the rest of the manufacturing locations.

HARDWARE/SOFTWARE PARACHUTE

Since the network is multivendor, GS found that they either had to embrace one common ISDN protection solution for all three forms of connectivity or deploy Cisco's ISDN solution for the LAN-to-LAN requirements, the Newbridge solution for the multiplexer-to-multiplexer connections, and come up with some kind of solution for the host-to-controller connections at the warehouses. That would mean learning, establishing, and maintaining three different recovery platforms.

When asked how they solved this dilemma, Gagnon says, 'Controlware Communications Systems, based in Neptune, N.J., attracted us because their ISDN backup offered a single solution that could be deployed around the world and would embrace all three platforms. Another advantage with this solution is that we are a global entity and Controlware products are certified for installation amongst the various PTTs throughout the world. We felt pretty comfortable that we could establish backup protection in most places we might have to deploy our network.'

General Semiconductor now has ISDN backup installed in five north American locations, six European locations, and one Asian location, with another five installations scheduled.

The company employs the Taxi system, which is located at GS' headquarters. These units automatically monitor permanent communications links and establish an ISDN connection to provide a backup path in the event of a failure. The ISDN dial backup (IDB) units used at remote sites are approved in 36 countries with data rates from 64 Kbps to 1.920 Mbps. They offer a wide range of configurations for connectivity for dial and leased line backup, including both PRI and BRI connections.

NMS TaxiDriver is a Windows-based network management system allowing alarm notification, remote configuration, event logfiles, remote testing, and inventory control. This module can be set to poll every element of the backup system at any interval to ensure the backup system is actually working and properly configured.

With the NMS module, Gagnon is able to manage the ISDN backup hardware worldwide from his office in Melville. He is currently configuring the system so that the units across the wide area can be controlled from any location. 'We test our ISDN backup network, on an automated basis, daily,' he says.

NOT A LOT - JUST CRITICAL

GS actually does not use a great deal of bandwidth, but according to Nick Mattera, director of technical services, what they send - and the constant ability to send - is quite important.

'Our bandwidth usage isn't particularly high, but it is very critical,' he says. 'We have customers all around the world. For instance, our Taiwan facility may need to send information to Germany in relation to parts inventory since a customer's location determines from which plant we ship parts. Taiwan relies very heavily on the billing process to come out of our main system here in Melville. If they are not able to print and attach invoices to shipping packages, they can't leave the loading dock.'

'EDI [electronic data interchange] is almost a quarter of the operational flow of this company,' says Mattera. 'Sales orders are received and processed in the sales offices throughout the world and entered into the sales system. This information has to be carried across the wide area to schedule and coordinate manufacturing.

'Upon manufacture, data needs to flow to the warehouses where shipping can be generated and product can be moved to the customer. Or, maybe product has to be received back from the customer. It's a very dynamic situation, on a daily basis.'

Mattera says the April 13 event 'paid General Semiconductor back every cent spent on the ISDN backup.'