To transport T1 video calls over fiber, you have some different options.
1 - most recommend, some cisco IP conferencing box with T1 interface. Dont's have the ID now but should be like VCxxx
2 - Use ISR router with VWIC and PVDM. In recent IOS release, video codecs are now supported.
3 - use T1 circuit emulation. That is a board that goes into a 2811 and bigger.
In all cases you will have covered calls to IP that is easyto convert to fiber, with a switch or an SFP directly in the router.
The fourth option would be a "dumb" T1 to fiber converter. Cisco doesn't make that. This and option 3 above require one videconf set to be configured a ISDN network side and internal clcok.
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