The Xelic Optical Transport Network (OTN) Time Sliced Framer Core (XCO23) performs Framer/Deframer functions and OTUk/ODUk/OPUk overhead processing for either 4xODU2/ODU2e or 1xODU3 frame rates. The XCO23 contains independent Transmit and Receive processors with time sliced external ports for overhead insertion and extraction with support for ODUk streaming and payload mapping modes of operation. Delay Measurement capability is provided in both Transmit (PM/TCMi) and Receive (TCMi) processors. Client and Line side data transfers use read enable and data valid signaling at clock rates up to 180 MHz to allow for flexible system clocking schemes. A flexible data bus architecture is used for ODUk/OTUk transport to provide 256-bit transfers for FPGA applications and 128-bit transfers for ASIC implementations.
The XCO23 Transmit Processor inserts OTUk, ODUk, and OPUk overhead, calculates and inserts parity, automatically generates Backward Defect Indication (BDI) signaling, and scrambles generated frames for all provisioned time slices. Support is provided for both asynchronous mapping procedure (AMP) and generic mapping procedure (GMP) justification methods. Programmable Trail Trace Identifier buffers are implemented for Section Monitoring (SM), Path Monitoring (PM), and Tandem Connection Monitoring overhead insertion. The XCO23 supports up to 6 levels of tandem connection overhead insertion and Interpret for all time slices. Diagnostics support includes optional corruption of inserted parity and maintenance signal insertion. Programmable payload support includes asynchronous, bit synchronous, GFP, null test, and PRBS mapping types.
The XCO23 Receive Processor contains a configurable frame alignment unit with programmable options for OOF/OOM and LOFLOM algorithm state transitions for all provisioned time slices. Incoming OTUk or ODUk frames are descrambled (optional) and aligned for OTN time sliced overhead processing. OTUk, ODUk, and OPUk overhead information is extracted to both time sliced internal register locations and an external overhead port. Frame alignment signal overhead is interpreted to detect and report various conditions which include OOF, OOM, and LOFLOM. Support is provided for both asynchronous mapping procedure (AMP) and generic mapping procedure (GMP) justification methods. OUT AIS, ODU AIS, ODU LCK, ODU OCI and client generic AIS maintenance signals are detected with optional interrupt generation. FTFL and up to 6 levels of TCM insertion and interpret is provided. OPUk payload type mismatch error conditions are detected and support is provided for programmable payload type accept and inconsistent thresholds.
Performance counters (configurable for error sync mode) are provided for the accumulation of inserted (XCO23 transmit processor) and detected (XCO23 receive processor) positive and negative justification events along with BIP-8 parity and BEI errors for OTU SM, ODU TCMi, and ODU PM (XCO23 receive processor) for all provisioned time slices. Counters are configurable for saturating latch and clear operation or periodic error sync auto-update mode.
The XCO23 provides facility and terminal loopback modes of operation using Transmit and Receive Processor data path configurations for system debug purposes.
A 16-bit generic register interface for access and configuration of internal memory mapped locations is included.