Tropic Networks Inc., based in Ottawa, Ontario, and Andover, Mass., said it has secured $10 million in financing , following a $60 million second venture-capital round earlier this year. Silicon Valley Bank, GATX/MM Venture Finance Partnership and Transamerica Commercial Finance Corp. led the latest round. The company said it will use the company for capital expenditures to support continued product-development initiatives and early customer acquisitions. Tropic Networks is developing optical packet networking systems to eliminate the constraints of delivering high bandwidth Internet Protocol and Ethernet-based services in metropolitan area networks.