This is what I get when I use the shieldsup tester pointing to the WAN IP of the router:
GRC Port Authority Report created on UTC: 2008-06-01 at 00:15:59
Results from scan of ports: 0-1055
0 Ports Open
1051 Ports Closed
5 Ports Stealth
---------------------
1056 Ports Tested
NO PORTS were found to be OPEN.
Ports found to be STEALTH were: 23, 80, 135, 443, 992
Other than what is listed above, all ports are CLOSED.
TruStealth: FAILED - NOT all tested ports were STEALTH,
- NO unsolicited packets were received,
- A PING REPLY (ICMP Echo) WAS RECEIVED.