I am experiencing problems retrieving data from <a href="http://www.namescout.com">www.namescout.com</a>.  
When I try to connect, the three-way TCP handshake is successful, but 
a HTTP request just hangs, with no response. 
 
This problem occurs from any machine on our /24 network 
(198.202.148.0/24), regardless of OS.  Curiously, when I try to make 
the request from our router, which uses its outward facing interface 
on a different IP block, the HTTP request is successful.  We are 
connected to the Internet via an OC3 and have no other &quot;unreachable&quot; 
sites, that we are aware of. 
 
I am looking for a diagnosis and possible solution of this problem.  I 
have included a tcpdump log, from the router, of the unsuccessful 
connection below.  Additional information is available upon request. 
 
Please note that the customer support information for Namescout is not 
an appropriate answer to this question.  Any answer should provide a 
detailed, technical explanation of the problem we are experiencing, 
along with possible solutions. 
 
tcpdump log: 
 
08:15:38.109982 198.202.148.18.4296 &gt; 64.86.0.44.http: S 
1310231346:1310231346(0) win 5840 &lt;mss 1460,sackOK,timestamp 413302504 
0,nop,wscale 0&gt; (DF) [tos 0x10] 
08:15:38.110031 198.202.148.18.4296 &gt; 64.86.0.44.http: S 
1310231346:1310231346(0) win 5840 &lt;mss 1460,sackOK,timestamp 413302504 
0,nop,wscale 0&gt; (DF) [tos 0x10] 
08:15:38.164314 64.86.0.44.http &gt; 198.202.148.18.4296: S 
2249860020:2249860020(0) ack 1310231347 win 17520 &lt;mss 1460,nop,wscale 
0,nop,nop,timestamp 0 0,nop,nop,sackOK&gt; (DF) 
08:15:38.164558 198.202.148.18.4296 &gt; 64.86.0.44.http: . ack 1 win 
5840 &lt;nop,nop,timestamp 413302509 0&gt; (DF) [tos 0x10] 
08:15:38.164594 198.202.148.18.4296 &gt; 64.86.0.44.http: . ack 
2249860021 win 5840 &lt;nop,nop,timestamp 413302509 0&gt; (DF) [tos 0x10] 
08:15:40.858430 198.202.148.18.4296 &gt; 64.86.0.44.http: P 1:17(16) ack 
1 win 5840 &lt;nop,nop,timestamp 413302778 0&gt; (DF) [tos 0x10] 
08:15:40.858463 198.202.148.18.4296 &gt; 64.86.0.44.http: P 0:16(16) ack 
1 win 5840 &lt;nop,nop,timestamp 413302778 0&gt; (DF) [tos 0x10] 
08:15:41.082543 64.86.0.44.http &gt; 198.202.148.18.4296: . ack 17 win 
17504 &lt;nop,nop,timestamp 3491349 413302778&gt; (DF) 
08:15:41.132433 198.202.148.18.4296 &gt; 64.86.0.44.http: P 17:19(2) ack 
1 win 5840 &lt;nop,nop,timestamp 413302806 3491349&gt; (DF) [tos 0x10] 
08:15:41.132498 198.202.148.18.4296 &gt; 64.86.0.44.http: P 16:18(2) ack 
1 win 5840 &lt;nop,nop,timestamp 413302806 3491349&gt; (DF) [tos 0x10] 
08:15:41.239632 64.86.0.44.http &gt; 198.202.148.18.4296: . 2897:2921(24) 
ack 19 win 17502 &lt;nop,nop,timestamp 3491350 413302806&gt; (DF) 
08:15:41.239866 198.202.148.18.4296 &gt; 64.86.0.44.http: . ack 1 win 
5840 &lt;nop,nop,timestamp 413302817 3491349,nop,nop,sack sack 1 
{2897:2921} &gt; (DF) [tos 0x10] 
08:15:41.239895 198.202.148.18.4296 &gt; 64.86.0.44.http: . ack 1 win 
5840 &lt;nop,nop,timestamp 413302817 3491349,nop,nop,sack sack 1 
{2897:2921} &gt; (DF) [tos 0x10] 
08:15:44.503194 64.86.0.44.http &gt; 198.202.148.18.4296: . 1449:1461(12) 
ack 19 win 17502 &lt;nop,nop,timestamp 3491383 413302817&gt; (DF) 
08:15:44.503417 198.202.148.18.4296 &gt; 64.86.0.44.http: . ack 1 win 
5840 &lt;nop,nop,timestamp 413303143 3491349,nop,nop,sack sack 2 
{1449:1461}{2897:2921} &gt; (DF) [tos 0x10] 
08:15:44.503458 198.202.148.18.4296 &gt; 64.86.0.44.http: . ack 1 win 
5840 &lt;nop,nop,timestamp 413303143 3491349,nop,nop,sack sack 2 
{1449:1461}{2897:2921} &gt; (DF) [tos 0x10] 
08:15:51.045493 64.86.0.44.http &gt; 198.202.148.18.4296: . 1449:1461(12) 
ack 19 win 17502 &lt;nop,nop,timestamp 3491449 413303143&gt; (DF) 
08:15:51.045761 198.202.148.18.4296 &gt; 64.86.0.44.http: . ack 1 win 
5840 &lt;nop,nop,timestamp 413303797 3491349,nop,nop,sack sack 3 
{1449:1461}{1449:1461}{2897:2921} &gt; (DF) [tos 0x10] 
08:15:51.045825 198.202.148.18.4296 &gt; 64.86.0.44.http: . ack 1 win 
5840 &lt;nop,nop,timestamp 413303797 3491349,nop,nop,sack sack 3 
{1449:1461}{1449:1461}{2897:2921} &gt; (DF) [tos 0x10] 
08:15:51.701687 64.86.0.44.http &gt; 198.202.148.18.4295: . 1449:1461(12) 
ack 20 win 17502 &lt;nop,nop,timestamp 3491455 413302259&gt; (DF) 
08:15:51.701923 198.202.148.18.4295 &gt; 64.86.0.44.http: R 
1269696398:1269696398(0) win 0 (DF) 
08:15:51.702017 198.202.148.18.4295 &gt; 64.86.0.44.http: R 
1269696398:1269696398(0) win 0 (DF) 

I don't understand exactly what's going on here.  Are you having this
problem on machines of differing operating systems all in that same
/24 netblock?  What operating system is running the query that the
above tcpdump shows?  It looks like you're running two separate TCP
streams, almost, on the same port.  There are two SYNs from you, and
one in response.  Then two ack's.  Etc.  Then two pushes of different
16-byte data packets.  I think something on your client machine is a
little screwey.
Could you tell me what you're doing to generate the above traffic, and
what's running on that source machine (198.202.148.18)?  I might be
able to help then.