3Com NETBuilder SI, SuperStack II Connector Model 43x and 53x Isdn S/T, Model 44x and 54x Isdn U

Cabling the Connectors 35

Cabling the WAN This section describes the WAN connector for each bridge/router model.

Connector

Model 43x and 53x ISDN S/T

Models 43x and 53x bridge/routers have an ISDN S/T connector.

WAN

(CSU/DSU)
Line	B1 B2
	Link
Act	Connect
Line
Error	Fault

ISDN S/T cable

ISDN-U BRI

Wall outlet

Network

termination

(NT1)/power

supply*

S/T interface	*required for U.S.	U interface
	and Canada only

The ISDN S/T port uses an RJ-45 connector. In the U.S. and Canada, purchase an NT1 from an ISDN equipment vendor, and use it between the bridge/router and the ISDN outlet. In other countries, you do not need to provide an NT1 because the function is provided by the ISDN equipment at the customer site.

For more information on ISDN cables, see “ISDN S/T Cable” on page 170.

Model 44x and 54x ISDN U

Models 44x and 54x bridge/routers have an ISDN U connector.

WAN

(CSU/DSU)

B1 B2

Line Link

Act

Connect

Line

Error Fault

ISDN-U BRI

wall outlet

ISDN U cable