Modular Routers
The modular routers had 3 interface slots available - 2 Synchronous Serial and 1 ISDN. The ISDN modules were keyed so as not to be inserted into a Synchronous WAN module slot.
The following modules were available:
- 2-wire, switched 56-kbit/s DSU/CSU (RJ11)
- 4-wire, 56/64-kbit/s DSU/CSU (RJ48S)
- Fractional T1/T1 DSU/CSU (RJ48C)
- Five-in-one synchronous serial (DB60) (Supported five signalling types - EIA/TIA-232, EIA/TIA-449, V.35, X.21 and EIA-530).
- ISDN BRI (S/T) (RJ45)
- ISDN with integrated NT1 device (U) (RJ45)
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