Nortel Meridian 1 Option 11C, Administration And Maintenance, Page: 17 / 507

Chapter 1 — ISDN Basic Rate Interface Page 3 of 492
Option 11C ISDN BRI Administration and Maintenance
Packet Data transmission - The Option 11 supports both B-channel and
D-channel packet data transmission through an external DPN-100 packet
handler.
ISDN BRI allows simultaneous voice, circuit-switched data, and packet data
transmission over a single DSL.
ISDN BRI provides two interface types to the Option 11:
—
S/T interface
, that provides a 4-wire multi-point connection. This
interface is provided by an NT6D70 SILC line card, which supports eight
DSLs.
—
U interface
, that provides a 2-wire point-to-point connection that uses
2B1Q line encoding. This interface is provided by an NT6D71 UILC line
card, which supports eight DSLs.
The following BRI functions are carried out by the NTBK22 Multi-Purpose
ISDN Signaling Processor (MISP) card on the Option 11:
— Each MISP can support up to four line cards (UILC or SILC or any
combination of the two). See Figure 1.
— The MISP executes Open System Interconnect (OSI) link and network
layer protocol. Refer to ISDN BRI protocol in this chapter for further
information.
— The MISP processes the signaling information received on the
D-Channels from DSLs. D-Channels may also carry user packet data,
which the MISP separates from signaling information and forwards to
the external DPN-100 packet handler.
— control terminal initialization and addressing
— assign B-channels for switched voice and data transmission
— send call control messages to ISDN BRI terminals over the D-channel
— supports a clock controller daughter board for BRI trunking applications