CS4805 AMCC [Applied Micro Circuits Corporation], CS4805 Datasheet - Page 2

• Manufacturer Part Number: CS4805
• Description: SONET/SDH STS-48/STM-16 Framer/Pointer Processor
• Manufacturer: AMCC [Applied Micro Circuits Corporation]

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DANUBE
SONET/SDH STS-48/STM-16 Framer/Pointer Processor
Overview and Applications
SONET Processing
The S4805 can be used in either SONET or SDH applications. On
the low-speed side, it can interface to 4 groups of either 1 STS-
12/STM-4 or 4 STS-3/STM-1 signals in each direction.
In the demultiplex direction, the S4805 accepts an STS-48/STM-
16 signal, either in 4-bit wide, 622 MHz or 16-bit wide, 155 MHz
format. There are then several modes of operation that the S4805
supports in the demultiplex direction.
For STS-48 only operation, the S4805 provides a full-bypass
mode, as well as a pointer processor bypass mode. In the full-
bypass mode, the S4805 simply passes the incoming STS-48/
STM-16 signal directly through to the demux output. Framing,
descrambling and TOH monitoring are performed off-line, in a
non-intrusive manner for monitoring purposes only. No pointer
processing, cross-connection or frame regeneration is performed.
In pointer processor bypass operation, the S4805 locates the
incoming STS-48/STM-16 frame, optionally descrambles the
data, and non-intrusively monitors the TOH. The STS-48/STM-16
signal is then passed directly to the frame generation block, in
which outgoing TOH overhead bytes can be provisionally regen-
erated, on a per function basis. Again, no pointer processing is
performed, and the cross-connect block is bypassed.
For applications requiring pointer processing, the S4805 locates
frame in the incoming STS-48/STM-16 signal, performs descram-
bling, monitors the TOH bytes, and then performs pointer pro-
cessing. The pointer processor provides a mode in which the
incoming TOH bytes transparently pass through the pointer pro-
cessor to the corresponding locations in the TOH of the outgoing
tributaries. The TOH bytes involved in this transparent pass-
through mode include the defined overhead bytes for the constitu-
ent STS-3/STM-1, STS-12/STM-4 or STS-48/STM-16 signals. A
192x48 cross-connect block is available after the pointer proces-
sor. This cross-connect can be used to select STS-1s from any of
the demuxed tributaries, tributaries from the low-speed mux
inputs, or tributaries from the DX and MX APS interfaces to place
into any one of the outgoing STS-1 time slots in any of the outgo-
ing signals in the demux direction. If this signal does not contain a
STS-48c/AU-4-16c payload, the S4805 can demultiplex the signal
to 4 groups of either 1 STS-12/STM-4 or 4 STS-3/STM-1 tributar-
ies. The selected tributaries then proceed in the demux direction
to frame generators that provisionally generate the TOH/SOH
bytes, perform scrambling, and output the data. Alternatively, the
overhead data can be transparently passed through the frame
generation block.
In the multiplex direction, the S4805 accepts a single STS-48/
STM-16 signal (4-bits wide, 622 MHz or 16-bit wide, 155 MHz), 4
serial STS-12/STM-4 (622 MHz) signals or 4 groups of 4 serial
(155 MHz) STS-3/STM-1 signals. There are several modes of
operation that the S4805 supports in the multiplex direction.
For STS-48 only operation, the S4805 provides a full-bypass
mode, as well as a pointer processor bypass mode. In the full-
bypass mode, the S4805 simply passes the incoming STS-48/
STM-16 signal directly through to the mux output. Framing,
descrambling and TOH monitoring are performed off-line, in a
Empowering Intelligent Optical Networks
non-intrusive manner for monitoring purposes only. No pointer
processing, cross-connection or frame regeneration is performed.
In pointer processor bypass operation, the S4805 locates the
incoming STS-48/STM-16 frame, optionally descrambles the
data, and non-intrusively monitors the TOH. The STS-48/STM-16
signal is then passed directly to the frame generation block, in
which outgoing TOH overhead bytes can be provisionally regen-
erated, on a per function basis. Again, no pointer processing is
performed, and the cross-connect block is bypassed.
For applications requiring pointer processing, the S4805 locates
the incoming STS-48/STM-16, STS-12/STM-4 or STS-3/STM-1
frames, descrambles the data, non-intrusively monitors the TOH/
SOH bytes and then performs pointer processing. The pointer
processor provides a mode in which the incoming TOH bytes
transparently pass through the pointer processor to the corre-
sponding locations in the TOH of the outgoing tributaries. The
TOH bytes involved in this transparent pass-through mode
include the defined overhead bytes for the constituent STS-3/
STM-1, STS-12/STM-4 or STS-48/STM-16 signals. A 192x48
cross-connect block is available after the pointer processor. This
cross-connect can be used to select STS-1s from the incoming
multiplex side signals, tributaries from the demux direction, or trib-
utaries from either the DX or MX APS interface. These selected
tributaries are then muxed into an STS-48/STM-16 signal. This
STS-48/STM-16 muxed signal then proceeds to a frame genera-
tor that provisionally generates the TOH/SOH bytes, performs
scrambling, and outputs the data. Alternatively, the overhead data
can be transparently passed through from the mux inputs to out-
put.
Low-Speed Interfaces
On the low-speed side, in both the mux and demux directions, the
S4805 supports either a 16-bit wide, 155 Mb/s STS-48/STM-16
signal, a 4-bit wide, 622 Mb/s STS-48/STM-16 signal, 4 serial
STS-12/STM-4 signals operating at 622 Mb/s or 4 groups of 4
serial STS-3/STM-1 signals operating at 155 Mb/s. The S4805 is
designed to bolt directly to fiber optic transceivers with built-in
clock data recovery.
High-Speed Interface
On the high-speed side, in both the mux and demux directions,
the S4805 supports either a 16-bit wide, 155 Mb/s or a 4-bit wide,
622 Mb/s STS-48/STM-16 signal.
Controller Interface
A high-speed microprocessor interface is provided for configura-
tion and monitoring. S4805 provides numerous automatic moni-
toring functions. It can be configured to provide an interrupt to the
control system, or it can be operated in a polled mode.
Applications:
• SONET/SDH add/drop multiplexers, terminal multiplexers, and
• WDM/DWDM Mux/Demux applications
digital cross connects.
Part Number S4805CBI11, Revision 1.5, January 2003
(See figure below.)
Product Brief