Confirmation of double routers is a command prompt, tracert .

Confirmation method of double routers. It can be checked easily in a command prompt. When being suspected of double routers, please check it by the following way.
It's explained by a way to WindowsXP, but Vista and Win7 in case of are also operation like most.
First a command prompt screen is taken out. "Program-> accessary-> command prompt of all start->"
Next a connecting path is indicated. When connecting to (tracert) which is a command prompt screen and indicates the process connected to some sites for example gurgling, it's a command prompt.

  tracert www.google.com

It's input and return (Enter) is done. The above?

  tracert 66.249.89.99

Even the above is OK.

  1     3 ms     1 ms     1 ms  air.setup [192.168.11.1]
  2     4 ms     1 ms     1 ms  ntt.setup [192.168.1.1]

Indication like the above comes out. I aim at the last number (the address). "192.168" etc. is a local address, so when 2 are indicated as mentioned above, you can judge double routers. When they aren't double routers conversely, it'll be the name of the provider of flets to be shown to the 2nd.
It's easy, so please try by all means. When they were double routers, release is needed. Separately, I write an article of release method.