TULSA, Okla., July 12 -- With the help of Corvis Corp. -- an all-optical networking company in Columbia, Maryland -- Williams Communications has set-up the longest all-optical terrestrial communications transmission to date, the company said.Williams Communications used Corvis' integrated line of networking products to send data on multiple OC-48 (2.5 Gb) optical signals across a more than 3200-km route on the Williams fiber-optic network without the hassle of electrical regeneration. This is five times larger than current technologies -- which require regeneration every 400-600 kilometers -- have produced, said Williams.