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VWIC-2MFT-T1

Quick question. Can I configure one port on a VWIC-2MFT-T1 for PRI and another for T1 data? Or would it be better to use 2xVWIC-1MFT-T1s?

3 REPLIES

Re: VWIC-2MFT-T1

The problem with this scenario is that both ports would have to use the same clock source. This could work, but it's unlikely to be stable in the long term. The 2nd generation VWIC2-2MFT-T1 cards support enhanced clocking allowing each port to use a seperate source, but only for data. This is not supported for voice. I would recommend seperate cards.

Hope this helps. If so, please rate the post.

Brandon

Hall of Fame Super Silver

Re: VWIC-2MFT-T1

I concur with Brandon, I attempted to use one card for both and voice sone time ago and had a lot if issues because of the clocking, ended up getting a seperate card for data.

Chris

Silver

Re: VWIC-2MFT-T1

If both ports are set as line, you will have 2 clocks driving the single Phase locked loop (PLL) clock recovery. This can sometimes lead to the PLL not being able to sync up to either clock reference and shows as slips on either of the ports.

A fix here is to can set the second port as clock source internal. The card's PLL will sync to the clock source on the first port, and use this recovered clock to drive the second port TX. Assuming both T1's are in sync externally, this will not cause any issues as the recovered clock being used to drive the TX on the second port is the same as the RX clock on this port.

If the two T1's are connected to dissimilar services that have different clocks then the only way to fix this is to use two single port cards or use the independent clock feature on the VWIC2 cards.

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