time out during tracert

First, I'd like to say that I really enjoy reading this site and it has the best subnetting tutorial I have seen. Very nice job guys!

I'm fairly new to networking and I have a quick question about tracert. How come so often when I use it some host along the way almost always times out as if it's unreachable but you can connect to a site with a browser fine?

Like for example, right now if I do tracert anandtech.com a bunch of hops in the end time out, and even ping anandtech.com times out, but I can still connect to a site with a browser. What does this mean?

This usually means that there is a firewall at the hop where it times out. This firewall has been told not to allow traceroute packets (with a low TTL value) through. As a result it times out.

You can sometimes get around this using traceroute on *nix boxes. Or using paratrace which traceroutes over a pre-established connection.