tmxf28155 ETC-unknow, tmxf28155 Datasheet - Page 402

• Manufacturer Part Number: tmxf28155
• Description: Tmxf28155 Super Mapper 155/51 Mbits/s Sonet/sdh X28/x21 Ds1/e1
• Manufacturer: ETC-unknow

155/51 Mbits/s SONET/SDH x28/x21 DS1/E1
18 SPE Mapper Functional Description
The SPE mapper basically interfaces to three other blocks within the Super Mapper device:
The interface between the SPE mapper and the VT mapper consists of clock, parallel data, sync, and control type
interfaces and is completely internal to the Super Mapper device.
The interface between the SPE mapper and the M13 MUX/deMUX consists of a serial clock, serial data, and clock
enable type interface and is also completely internal to the Super Mapper device.
The interface between the SPE mapper and the TMUX consists of the telecom bus and every signal that flows
between these two blocks is also brought in/out through external device pins connected to the telecom bus.
As outlined in the features, the SPE mapper can map/demap seven TUG-2 or a DS3 to/from AU3/STS-1 or TUG-3.
Each TUG-2 assembled/disassembled by the VT mapper consist of three TU-12 (E1) or four TU-11 (DS1) virtual
tributaries.
The following is a brief description of the supported standards based mappings. For greater details, please refer to
the appropriate standard.
18.4 TUG-2 to AU-3/STS-1 SPE Mapping (Used in North American Systems)
A TUG-2 payload capacity, which is 9 rows by 12 columns or 108 bytes, may contain four TU-11s or three TU-12s
byte interleavingly multiplexed.
The 27-byte capacity of a TU-11 is equivalent to three-column capacity in an STS-1 frame of 125 µs. Four TU-11s
are byte interleavingly multiplexed into a TUG-2 payload capacity which has a capacity of 12 columns. Seven
TUG-2s can then be byte interleavingly multiplexed into the payload capacity of a VC-3. The VC-3 has a structure
of 9 rows by 85 columns: one column is VC-3 path overhead and the other 84 columns are seven TUG-2s evenly
distributed within the payload. Two columns of fixed stuffing are then added to the payload to build the complete
STS-1 SPE frame of 9 rows by 87 columns.
The 36-byte capacity of a TU-12 is equivalent to four-column capacity in an STS-1 frame of 125 µs. Three TU-12s
are byte interleavingly multiplexed into a TUG-2 payload capacity which has a capacity of 12 columns. Seven
TUG-2s can then be byte interleavingly multiplexed into the payload capacity of a VC-3. The VC-3 has a structure
of 9 rows by 85 columns: one column is VC-3 path overhead and the other 84 columns are seven TUG-2s evenly
distributed within the payload. Two columns of fixed stuffing are then added to the payload to build the complete
STS-1 SPE frame of nine rows by 87 columns.
18.5 TUG-2 to TUG-3 Mapping (Used in ITU/ETSI Standard Based Systems)
A TUG-2 payload capacity, which is nine rows by 12 columns or 108 bytes, may contain four TU-11s or three
TU-12s byte interleavingly multiplexed.
The 27-byte capacity of a TU-11 is equivalent to three-column capacity in an STM-1 frame of 125 µs. Four TU-11s
are byte interleavingly multiplexed into a TUG-2 payload capacity which has a capacity of 12 columns. Seven
TUG-2s can then be byte interleavingly multiplexed into the payload capacity of a TUG-3. The TUG-3 has a struc-
ture of nine rows by 86 columns: one column of NPI (null pointer indication) plus fixed stuffing bytes, one column of
fixed stuffing and the other 84 columns are seven TUG-2s evenly distributed within the TUG-3 payload.
The 36-byte capacity of a TU-12 is equivalent to four-column capacity in an STM-1 frame of 125 µs. Three TU-12s
are byte interleaving multiplexed into a TUG-2 payload capacity which has a capacity of 12 columns. Seven
TUG-2s can then be byte interleavingly multiplexed into the payload capacity of a TUG-3.
402
The VT mapper.
The M13 MUX/deMUX.
The TMUX.
(continued)
Agere Systems Inc.
May 2001