This counts the number of TED probes dispatched by all dynamic cryptomaps on this managed entity since bootup, per its description, and like the received counter is unaffected by CLI operations. It reflects how actively this device is trying to discover the addresses of potential remote IPsec peers for dynamically-triggered tunnels, which matters in a spoke-to-spoke VPN design where endpoints aren't known in advance. A spoke router generating steadily increasing probe counts as new traffic destined for unknown peers arrives is the expected behavior of a functioning TED-based dynamic mesh.