Mac terminal user name becomes bogon and traceroute is strange

I was doing some traceroute test yesterday, and today, my Mac terminal's user prompt becomes

`bogon:~ myUserName$`

Also when I'm doing traceroute like:

traceroute www.google.com

it stops with this log:

bogon (192.168.0.1)  1.158 ms  0.908 ms  0.746 ms

192.168.0.1 is the address of my wireless router. I still can surf the internet though.