Caspian Networks, a one-time core router startup that today makes devices to improve network performance, is on the block.The San Jose, Calif., company is considering a possible acquisition deal, said Tom Gibson, a spokesman for Morgenthaler Ventures, an investor in Caspian. He declined to give more details, and Caspian President and Chief Executive Officer Brad Wurtz could not be reached for comment.Early in this decade, Caspian said it was building a massive IP routing switch that could be expanded through using multiple linked hardware platforms with distributed software. It would segment traffic into separate "flows" that would receive different treatment, allowing for guaranteed quality of service. But the platform didn\u2019t gain much traction with carriers, and like other big carrier-gear vendors, Caspian hit hard times when the telecommunications bubble burst. A news report Thursday said the company had shut down. Caspian was richly funded by venture investors and pulled in US$55 million in a funding round as recently as last year. Among the founders of Caspian was Internet pioneer Lawrence Roberts, who made dire predictions while at the helm of the company about Internet traffic growing far faster than the capacity of core routers, which are computers that transfer extremely large volumes of traffic on the Internet. Roberts has since left the company.Today, Caspian sells two Media Controller devices designed to let enterprises and service providers enforce quality-of-service policies. They also let carriers allocate bandwidth to users based on how much they pay, according to the company\u2019s website. Earlier this year it announced customer deals with Chunghwa Telecom of Taiwan and China United Telecommunications.-Stephen Lawson, IDG News Service (San Francisco Bureau)Check out our CIO News Alerts and Tech Informer pages for more updated news coverage.