Data Sheet
June 2002
TMXF28155 Supermapper
155/51 Mbits/s SONET/SDH x28/x21 DS1/E1
17 TMUX Functional Description (continued)
17.1 TMUX Introduction
The TMUX multiplexer block implements SDH/SONET-compliant, byte-interleave multiplexing/demultiplexing,
overhead insertion and termination, multiplex section protection (MSP) 1 + 1 switch capability, and serializer/dese-
rializer for 155.52 Mbits/s and 51.84 Mbits/s traffic.
As shown in Figure 24 on page 371, the TMUX provides three modes of operation: STS-3 mode, STM-1 mode,
and STS-1 mode. In STS-3 mode, the TMUX implements the functions necessary to multiplex and demultiplex up
to three STS-1 signals to/from a SONET STS-3 signal. In STM-1 (VC-4) mode, the TMUX provides the functionality
to multiplex and demultiplex up to three TUG-3 signals to/from an STM-1 (VC-4) signal. The device can also build/
extract up to three AU-3 signals to/from an STM-1 (VC-3) stream. In STS-1 mode, the TMUX implements the func-
tions necessary to interface a single STS-1 to/from an external serial link.
On the high-speed side or line side, the block can be configured for either a 155.52 Mbits/s (STS-3/STM-1) or
51.84 Mbits/s (STS-1) serial data interface. On the low-speed side or tributary side, the TMUX provides a byte-
wide bus that can communicate with up to three STS-1/TUG-3/AU-3 devices at a 19.44 MHz rate. If single STS-1
mode is employed, the bus rate will be 6.48 MHz. The TMUX therefore provides complete multiplexing/demulti-
plexing to/from an STS-3/STM-1 signal for up to 84 DS1, 84 JT1, or 63 E1 signals. In STS-1 mode, the TMUX pro-
vides multiplexing/demultiplexing for up to 28 DS1, 28 JT1, or 21 E1 streams. In STS-3/STM-1 mode, the TMUX
from only one device is required. The TMUX in other connected devices may be powered down to reduce con-
sumed power. This architecture allows flexible and modular growth in equipment capacity for both 51.84 Mbits/s
and 155.52 Mbits/s links.
17.2 TMUX Features
■ Multiplexes three STS-1 signals into a SONET STS-3 signal.
■ Multiplexes three VC-3 signals into an SDH STM-1 (AU-4) signal via a TUG-3 construction.
■ Multiplexes three VC-3 signals into an SDH STM-1 (AU-3) signal.
■ Demultiplexes three STS-1 signals from a SONET STS-3 signal.
■ Demultiplexes three VC-3 signals from an SDH STM-1 (AU-4) signal via a TUG-3 deconstruction.
■ Demultiplexes three VC-3 signals from an SDH STM-1 (AU-3) signal.
■ Provides STS-1-only mode for receive and transmit directions.
■ Provides complete functionality for SDH MSP 1 + 1 protection switching.
■ Detects STS-3/STM-1 loss-of-signal (LOS) conditions.
■ Detects STS-3/STM-1 out of frame and loss-of-frame (OOF/LOF) conditions.
■ Provides an 8-bit parallel bus interface that can accommodate up to three STS-1/AU-3s.
■ Provides STS-3/STM-1/STS-1 selectable scrambler/descrambler functions and B1/B2/B3 generation/detection.
■ Provides STS-3/STM-1/STS-1 pointer interpretation. Detects AIS-P and LOP.
■ Complies with GR-253-CORE, T1.105, G.707, G.783, G.806, G.821, and ETSI 417-1-1.
Agere Systems Inc.
367
ETC [ ETC ]
