Bit Field Guide

TTL

Network 1 octet IPv4 datagram unverified

Hop limit. Decremented by each router; the packet dies at zero.

Where it sits

IPv4 Datagram > TTL

Open in the explorer — TCP over IPv4, in a protected QoS Data frame, aggregated
Open in the explorer — ICMP echo over IPv4, in a QoS Data frame
Open in the explorer — TCP over IPv4, in a protected QoS Data frame
Open in the explorer — TCP over IPv4, in an open QoS Data frame
Open in the explorer — UDP over IPv4, in a QoS Data frame

Accuracy

Clause: RFC 791 §3.1
Verified: Not verified against the standard. Treat this as a claim, not a fact.