The Cisco RFGW-10 DS-48 card is similar to the traditional QAM solutions where the card receives encapsulated data, de-packetizes/re-formats the packets, maps them to the output QAM channel, and performs QAM modulation and frequency upconversion. From a high level, the DS-48 line card receives Video and DOCSIS data encapsulated over Ethernet and outputs analog QAM data to the subscriber devices (STB, DOCSIS modems).
As a DOCSIS engine, the Cisco RFGW-10 DS-48 line card supports DEPI D-MPT mode (future SW releases may support PSP mode). DEPI is based on the L2TPv3 protocol, which includes a data plane and a control plane. DEPI data plane traffic is terminated at the line card. The Cisco RFGW-10 Supervisor terminates DEPI control and communicates the control to each line card in the system via the chassis IPC infrastructure. DOCSIS timing information (10.24MHz synchronous DTI clock) is received by the line card from the system TCC cards.
As a video engine, the Cisco RFGW-10 DS-48 terminates video data path traffic forwarded from the Supervisor Engine (video control plane traffic is terminated and processed by the system Supervisor). The Cisco RFGW-10 DS-48 processing path classifies video packets, performs inter QAM processing, bitrate scheduling, program muxing/scheduling, PID remapping, PCR re-stamping, and CC re-stamping.
A critical feature for the Cisco RFGW-10 DS-48 line card is redundancy and high availability support. The line cards are designed to detect and react to a wide range of faults and failures and respond with sub-second failover to a dedicated protect card.
The Cisco RFGW-10 DS-48 line card is designed to support a wide range of line card health conditions and initiate failover events if considered catastrophic:
QAM or upconverter hardware failure. The line card monitors both the digital and RF data integrity. The modules also provide a comprehensive alarm structure to the system CPU, which allows constant monitoring of the UPX
Environmental alarms (temperature, voltage, frequency)
Software kernel failures
Software module failure
DTI Clock or Timing failures (both internal and external)