Cabletron Systems HSIM-W6 manual Isdn

Chapter 2: About the HSIM-W6

ISDN

ISDN provides an inexpensive switched digital access to remote sites. The ISDN BRI standard provides for two high speed 64 Kbps bearer (B) channels used for voice or data connections and one 16 Kbps signaling data (D) channel used for call setup, signaling and other information. ISDN allows all types of information to be transmitted including voice, data, fax and video. Multiple devices can be linked to a single ISDN connection, each having their own telephone number. Two or more channels can be combined into a single larger transmission pipe offering variable transmission speeds.

The HSIM-W6 supports one ISDN BRI line and either or both of the B channels for transferring data. If the two B channels are used for separate connections, each provides up to 64 Kbps transfer rates. Both channels can be used together to provide uncompressed data transfer at up to 128 Kbps. The HSIM-W6 can also transfer compressed data at up to 512 Kbps.

A Network Terminator device (NT1) provides the interface between ISDN terminal (router) equipment and the ISDN service provider. In the U.S., the NT1 is provided by the customer; outside the U.S., the NT1 is provided by the ISDN service provider. The HSIM-W6 supports the WPIM-S/T that provides an S/T interface requiring an external NT1.

Telephone Switch Support

The following telephone switch types are supported within the U.S.:

•National ISDN 1 (NI-1)

•AT&T 5ESS w/Custom Software

•DMS-100

Outside of the U.S. the following switch types are supported:

•NET3 (European ISDN)

•NET3SW (European Swiss-variant)

•NTT (Nippon Telegraph and Telephone)

•KDD (Kokusai Denshin Denwa Co., Ltd.)

•French Delta (VN4) switches

14 HSIM-W6 User’s Guide