3Com 3C63311 Reference Guide - Page 193

Using Loopbacks 181 OC3/STM-1 Loopbacks The following loopbacks are available for the OC3/STM-1 interface: Network LIne-Loops the OC3/STM-1 received data back on the output side after the digital data has been recovered. Local Card-Loops the transmit OC3/STM-1 output on the receive side; the transmitted data will continue to go on the output. Figure 139 illustrates the loopbacks for OC3/STM-1. Figure 139 OC3/STM-1 Loopbacks OC3 Interface Network Side Local Card Network Line Payload DS3 Loopbacks The DS3 module supports the following loopbacks: Local Card-Loops the transmit DS3output on the receive side. All cells coming from the DS3 card are looped through the backplane and back to the DS3 card. The transmitted data will continue to go on the output. Network Line-Loops the DS3 received data back on the output side after the digital data has been recovered. Network Card-Loops the DS3 received cell payload back toward the line output. Figure 140 illustrates the DS3 loopback options. Figure 140 DS3 UNI Loopback Options Network Side DS3 Interface Bus Side Network Card Network Line Local Card