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Re: [Full-disclosure] abnormal behavior Gmail logon



On 5/31/06, Valdis.Kletnieks@xxxxxx <Valdis.Kletnieks@xxxxxx> wrote:
On Wed, 31 May 2006 09:23:08 BST, Edward Pearson said:
> This isn't abnormal or weird, It happens when your internet connection
> is fairly slow and its because you sometimes receive incomplete headers
> for the page (broken or garbled)

If you have noisy hardware that's mangling data in transit, the mangling will
*usually* be detected by the checksums on each IP packet.  The reason your
connection gets slow is because if a corruption is detected, the packet gets
thrown out, and needs to be retransmitted by the sending system.

It is actually possible that the data sent in the HTTP connection is
getting mangled even though the TCP checksums are correct.  In one
mode of operation, HTTP allows a server to indicate when a document is
complete simply by closing a TCP connection.  If the server gets busy,
it might decide your client is just too slow to be worth dealing with
and close the connection early.  Servers are supposed to send RST
packets when they do that, but not all servers do it, and not all
clients recognize those RST packets as indicating that the document
they just downloaded is incomplete.

Regards,
Brian

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