What is TRACERT?

The TRACERT diagnostic utility determines the route taken to a destination by sending Internet Control Message Protocol (ICMP) echo packets with varying IP Time-To-Live (TTL) values to the destination. Each router along the path is required to decrement the TTL on a packet by at least 1 before forwarding it, so the TTL is effectively a hop count. When the TTL on a packet reaches 0, the router should send an ICMP Time Exceeded message back to the source computer.

TRACERT determines the route by sending the first echo packet with a TTL of 1
and incrementing the TTL by 1 on each subsequent transmission until the target
responds or the maximum TTL is reached. The route is determined by examining the ICMP Time Exceeded messages sent back by intermediate routers. Note that some routers silently drop packets with expired TTLs and are invisible to TRACERT.

TRACERT prints out an ordered list of the routers in the path that returned the
ICMP Time Exceeded message. If the -d switch is used (telling TRACERT not to
perform a DNS lookup on each IP address), the IP address of the near- side
interface of the routers is reported.

Note: Not all machines on the internet will respond to a tracert or ping, this may be for security reasons and not as a result of a problem.