By Andrew Chung


NEW YORK (Reuters) - Arista Networks Inc used rival Cisco Systems' network device technology in its ethernet switches without permission, a U.S. trade judge ruled on Friday, handing Cisco yet another win in a sprawling legal battle over patents between the two companies.


The judge, MaryJoan McNamara of the U.S. International Trade Commission in Washington, said that Arista had infringed two patents owned by Cisco. The ruling, which must be reviewed by the full commission over the next few months, could lead to an order banning the import of Arista's products into the United States.


Cisco filed the complaint at the ITC in December, 2014, alleging that Arista was infringing six of its patents, which relate to improving the speed and performance of networked computers and devices.


The products accused of infringement include Arista's 7000 series of switches, which generate most of that company's revenues.


Wednesday's ruling comes after the ITC in June, in a separate case, ordered an import ban on Arista's products that infringed several other Cisco patents.

The U.S. Trade Representative allowed that order to go ahead in August, but U.S. customs officials last month ruled that Arista could resume imports of its redesigned switches because they were not within the scope of the ban.

(Reporting by Andrew Chung; Editing by Bernard Orr)