3.3.3.3.1. Requirements for ISDN (S0) Data (Connections) 
IMPORTANT:
For basic information on installing S0 data scenarios
refer to the description of how to install S0 subscribers and S0 trunking
scenarios. This section describes the special requirements for S0 data
connections that also have to be taken into consideration.
- ISDN data connections are only supported if Mediatrix 44xx gateways are used.
- ISDN data connections are only supported for stations or trunks that are configured on the same OpenScape 4000 SoftGate.
IMPORTANT:
Direct Media over LAN (DMC) is not possible for S0 data
connections.
- All ISDN S0 gateways for data connections should be synchronized with a common clock. For instance, the gateways receive the clock pulse via a direct connection to the public network or via an internal ISDN line (layer-2 connection) to another synchronized gateway.