This counts the total number of valid packets transmitted over this specific pseudowire service instance. Comparing TxPkt on this PW against the remote end's RxPkt (where visible) is how an admin estimates one-way packet loss across the network path carrying this specific service -- and this specific object covers a cumulative counter reset only by an explicit clear rather than on a fixed schedule -- reflecting everything since PM stats were last cleared. For example, since PM counters were last cleared, this pseudowire might show this counter at 9000000 -- a concrete count the admin can trend against neighboring bins to judge whether the condition it reflects is worsening.