For ISPs with available optical technology, the Cisco 10000 ESR supports a channelized OC-12 line card. The line card is configured with an SC duplex connector supporting single-mode, intermediate-reach optics. The module supports 12 separate STS-1 signals, each capable of carrying DS3 (full rate or subrate), 28 individual DS1 channels, nxDS0 up to 24 DS0 channels per DS1, or 28 individual VT1.5 channels. Each of the 12 separate STS-1 signals is multiplexed over an STS-12 (OC-12) port and supports up to 768 channels per card with any mixture of DS3, nxDS1, or nxDS0 (as long as the total number of channels does not exceed chassis scaling limits, and no more than 192 channels are assigned within a single STS-3).The channelized OC-12 line card can be used in any Cisco 10000 interface card slot and can be hot-swapped. The line card is fully manageable through the use of standard Cisco management tools, and it supports all IP networking protocols.