That’s not a straightforward question. The NIDU encapsulates TDM data in Ethernet frames for transmission to the NIDU at the remote end of a wireless link, and the PTP 650/700 wireless link forwards Ethernet frames between the NIDUs. A pseudo-wire is defined as emulation of a circuit by transmission over a packet data network. From this perspective, the NIDUs must be classified as pseudo-wire devices.
However, the TDM service in PTP 650/700 provides very precise synchronization between NIDUs, building on the synchronization of the two ODUs and the tight integration between the NIDUs and ODUs. The excellent wander and low latency provided by the PTP 650/700 NIDU solution are competitive with native TDM solutions, and are significantly better than the performance achieved with generic standards-based pseudo-wire solutions.
Many other frequently-asked questions are answered here: ptp-nidu-faq