http://netalyzr.icsi.berkeley.edu/
Exemple:
Major Abnormalities
    * No DNS Port Randomization 
Minor Aberrations
    * Certain protocols are blocked in outbound traffic
    * An HTTP proxy was detected based on added or changed HTTP traffic
    * Your computer's clock is slightly fast 
Address-based Tests
NAT detection: NAT Detected
Your global IP address is 10.0.1.2 while your local one is 192.168.200.206. You are behind a NAT. Your local address is in unroutable address space.
Your NAT renumbers TCP source ports sequentially. The following graph shows connection attempts on the X-axis and their corresponding source ports on the Y-axis.
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