... . cisco NM-HDV network modules are installed in fixed network module slots on Cisco routers,Cisco switches such as 2600 series, Cisco 3600 series, Cisco 3700 series, and Cisco ... MWR 1941-DC routers, and in configurable network module slots on Cisco 2811, Cisco 2821, Cisco 2851, and Cisco 3800 series routers. cisco NM-HDV network modules