Meaning of tracert output?

C:\>tracert www.google.com

Tracing route to www.l.google.com [209.85.143.99]
over a maximum of 30 hops:

  1    <1 ms    <1 ms    <1 ms  server88-208-200-1.live-servers.net [88.208.200.1]
  2    <1 ms    <1 ms    <1 ms  88.208.255.101
  3     5 ms     5 ms     5 ms  88.208.255.62
  4     *        *        *     Request timed out.
  5     5 ms     5 ms     5 ms  209.85.252.76
  6    16 ms    25 ms    16 ms  209.85.251.190
  7    22 ms    16 ms    16 ms  209.85.253.125
  8    16 ms    25 ms    28 ms  216.239.47.26
  9    17 ms    17 ms    16 ms  dy-in-f99.1e100.net [209.85.143.99]

Trace complete.

What do the results mean?

Each hop is represented by a different line (although the Command Prompt will wrap lines that are two long to fit the width of the window). Each hop is numbered, so you can see that this trace took 9 hops to reach the destination server, dy-in-f99.1e100.net [209.85.143.99], which serves the Google website.

Each row is displayed in 5 columns. The first column is simply the number of the hop.

1    <1 ms    <1 ms    <1 ms  server88-208-200-1.live-servers.net [88.208.200.1]

Traceroute will actually send three packets of data, and measure the time taken for each. In the hop of our results you can see that each packet took less than a millisecond, which is shown as <1 ms. You can also see that the server at hop 1 is called server88-208-200-1.live-servers.net, and it's address on the Internet is 88.208.200.1.

From these results you can see that it took between 16 and 17 milliseconds to retrieve data from the destination server, as shown in the last hop.

9    17 ms    17 ms    16 ms  dy-in-f99.1e100.net [209.85.143.99]

What does Request timed out mean?

Hop number 4 in the results shows no time data and a Request timed out error. This is because the server at hop four is not accepting Internet Control Message Protocol (ICMP) traffic. As a result it ignores Traceroutes request for information. As you can see, however, it has still sent the data to the next hop as there are results that follow.

The Request timed out error message is usually nothing to worry about, as many network providers may disable ICMP traffic if their network is under heavy load.