This document has been reviewed as part of the transport area review team's ongoing effort to review key IETF documents. These comments were written primarily for the transport area directors, but are copied to the document's authors and WG to allow them to address any issues raised and also to the IETF discussion list for information. When done at the time of IETF Last Call, the authors should consider this review as part of the last-call comments they receive. Please always CC tsv-art@ietf.org if you reply to or forward this review. If I understand things correctly, an LSP ping packet is a UDP/IPv4 or UDP/IPv6 packet and the processing described in this document can increase the size of such a packet. I am wondering how IP level fragmentation is avoided, in case the packet gets larger than the MTU. Nit: Section 3: Reply Path (RP) TLv -> Reply Path (RP) TLV