You will need vwic2 1mft E1/T1
That will allow the physical connection of an ISDN30 PRI (E1 =30 channels , T1 24 Channels)
You also require a DSP chip to converts the POTS or PRI to IP packets
For E1/T1 you need
PVDM2-32 to enable all channnels
This plugs in to the PVDM slot on the motherboard of the router ( Yes Lid off)
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