Comtrol Achieves Performance Breakthrough in Network Serial Data Communications

April 1, 2003
MINNEAPOLIS -- Comtrol Corporation, the leading U.S. provider of multiport serial-to-Ethernet device connectivity and management products, announced today

MINNEAPOLIS -- Comtrol Corporation, the leading U.S. provider of multiport serial-to-Ethernet device connectivity and management products, announced today that it has achieved a performance breakthrough that will enable expanded use of low-cost, highly reliable network serial port servers, enabling them to connect remotely located serial devices to the application software programs with which they interoperate. Delays in communicating across the network (latency) had previously been the single most significant factor inhibiting the widespread use of this technology, forcing serial connections to remain tightly coupled with PC servers. The new performance reported by Comtrol can resolve this issue in the vast majority of cases, allowing substitution of Ethernet for expensive serial cabling.

Company officials disclosed the performance breakthrough as part of a report summarizing the results from a performance test of its products against its primary competitors. Called the "Serial Shoot-Out," the test measured the elapsed time required to send a one byte block of data from a program running on a PC server, over the Ethernet to a network serial port, and back again. The round-trip test was run 10,000 times for each tested server and then repeated, with the average of the 20,000 iterations used as the final performance number. Quicker round-trip elapsed time demonstrates greater efficiency of the network serial port server.

For comparative purposes, the benchmark was also executed on the onboard serial port of a PC server running Microsoft Windows 2000, because integrated serial ports are the defacto standard for connecting serial devices that are "latency sensitive." With millions of PCs installed worldwide that communicate with attached serial devices, the PC serial port's efficiency is seen as the "standard to beat" by the emerging network serial port servers. Interest in deploying network serial port servers is growing steadily because using a LAN or the Internet in lieu of serial cabling is a very powerful and cost-effective solution. Industry insiders believe that if a network serial port server can achieve throughput equivalent to an integrated serial port, it can then be a viable replacement technology for PC servers with internal serial expansion cards.

Benchmark results revealed a 5.35 millisecond elapsed time for the integrated PC serial port and 8.55 milliseconds for Comtrol's DeviceMaster network serial port server. When Comtrol's Rapid Transport Service(tm) communication protocol was substituted for the industry-standard TCP/IP protocol used to test all of the products, throughput improved to 5.91 milliseconds--less than one half of a millisecond slower than the directly connected serial ports. Network serial port servers from Digi International (Nasdaq: DIGI) and Lantronix, Inc. (Nasdaq: LTRX) were also tested. The two Digi products tested performed 6-21 times slower than the four Comtrol products tested. The three Lantronix products tested performed 30-88 times slower than the four Comtrol products tested. Clearly, the Digi and Lantronix products incurred significantly more latency than the Comtrol products.

Comtrol officials said that its DeviceMaster family of serial port servers uses both hardware and software to achieve the breakthrough performance. The company has filed patents to protect its technology and performance advantage.

To confirm the results of its testing, Comtrol contracted with an independent test service. Comtrol's Serial Shoot-Out White Paper includes the test methodology, performance results achieved through Comtrol and the test service, and a copy of the test program itself so that the test can be performed by anyone. The report is available to interested parties that visit Comtrol's Web site at and request a copy.

Company management warned that factors beyond its control, such as network traffic congestion, can have a negative performance impact diminishing these results. When throughput is a paramount concern, Comtrol said that customer engineers could create a network topology that can minimize the potential for the type of congestion that could degrade throughput performance.

"Using DeviceMaster to provide serial data communications over a network is like driving a sports car on the Interstate highway," remarked Lee Stagni, president and COO of Comtrol. "The car has enough power to make a quick trip, but if the trip is taken during rush-hour, you could easily be late for dinner." The solution, Comtrol says, is to make sure that DeviceMaster operates over a low-overhead network. "DeviceMaster provides the horsepower," said Stagni, "our customers just need to give us the Express Lane to drive in."

For more information about Comtrol's device connectivity solutions, contact Comtrol at 800-GO-ROCKET or visit Comtrol's Web site at

Comtrol Corporation, based in Minneapolis, is a leading global provider of device connectivity, data communications, and enterprise integration software technologies. For additional information, visit the Comtrol Web site at or call 800-926-6876.