HWIC-4T Cisco 4-Port Serial High-Speed WAN Interface Card Four high-speed serial ports Supported Platforms HWIC Product Number Cisco 1841 ISR Cisco 1941 ISR Cisco 2800 Series Cisco 2900 Series Cisco 3800 Series Cisco 3900 Series HWIC-4T No No Yes Yes Yes Yes HWIC-4A/S Yes Yes Yes Yes Yes Yes HWIC-8A/S-232 Yes Yes Yes Yes Yes Yes HWIC-8A Yes Yes Yes Yes Yes Yes HWIC-16A No No Yes Yes Yes Yes SM-32A No No No Yes No Yes HWIC Specifications Specification HWIC-4T HWIC-4A/S HWIC-8A/S-232 HWIC-8A HWIC-16A SM-32A Synchronous support Yes Yes Yes No No No Synchronous maximum speed (per port) 8 Mbps 256 kbps 256 kbps - - - Asynchronous support Yes Yes Yes Yes Yes Yes Asynchronous maximum speed (per port) 230.4 kbps 230.4 kbps 230.4 kbps 230.4 kbps 230.4 kbps 230.4 kbps Bisync support Yes Yes Yes No No No Serial protocols EIA-232, EIA-449, EIA-530, EIA-530A, and V.35, X.21 EIA-232, EIA-449, EIA-530, EIA-530A, and V.35, X.21 EIA-232 EIA-232 EIA-232 EIA-232 Lead manipulation Yes Yes Yes Yes Yes Yes Network clock synchronization Yes Yes Yes No No No