求翻译：通过向目标发送不同 IP 生存时间 (TTL) 值的“Internet 控制消息协议 (ICMP)”回应数据包，Tracert 诊断程序确定到目标所采取的路由。要求路径上的每个路由器在转发数据包之前至少将数据包上的 TTL 递减 1。数据包上的 TTL 减为 0 时，路由器应该将“ICMP 已超时”的消息发回源系统。是什么意思？

Sent to target different ip Time to Live (ttl) value of the "Internet Control Message Protocol (icmp), the response packet, tracert diagnostic procedures to determine the route taken by the target. Each router in the path is required at least before forwarding the packet to the packet ttl is decreme

By sending the target a different IP time to live (TTL) value, "Internet Control Message Protocol (ICMP)" in response to packets, Tracert diagnostic procedures to determine routes taken to the target. Each router along the path is required to at least on a packet before forwarding the packet's TTL w