This read-only counter tracks output CLNP PDUs that encountered no other transmission problem but were discarded anyway, for example due to a lack of buffer space, and this counter does include PDUs that were also counted as forwarded traffic in clnpForwPDUs. An admin watching this rise under load would suspect outbound buffer exhaustion, and because forwarded PDUs are included, a busy intermediate system might show this counter climbing even when its own locally originated traffic is light. For example, a router forwarding a heavy burst of transit traffic that exceeds its outbound buffering capacity would see this counter increase even if none of the discarded packets originated locally.