Juniper's PE-10CHEI-RJ48 Module is loop-back supported on all interface speeds. It
has remote payload loop-back, local line loop-back, remote line loop-back, and each
channel can be looped back individually and independently. Mapping granularity: each DS3/STS1 is individually configurable. Alarm indication signal -line (AIS-L), alarm indication signal - path (AIS-10-port E1/ channelized E1 PIC PE-10CHE1-RJ48-PPN 10-
port E1/ channelized E1 PIC, and more.