TFTP timeout and maximum retry counts in "tftp.h"

[Mike Hammer <mike-hammer@usa.net>]

Hello,

In the header file, "tftp.h", the values for TFTP_RETRY and
TFTP_TIMEOUT are set to 10 and 144 (8 seconds) respectively.
I'm trying to understand this values to solve the problem
i'm currently having which is timeouts and excessive retries.

Is the TFTP timeout value an initial timeout, i.e. first
timeout is set to 8 seconds and afterwards, the timeout values
are exponentially increased for each retries?

Thus, using the maximum retry counts and timeout value,
does this mean that a retry will be performed (to receive
the same data block) after a timeout of 8 seconds trying
to receive a block of data?  And after 10 total retries, 
TFTP will fail and bail out?

Finally what does it mean when the TFTP client displays,
"block x != block y" during transfer.  After the display,
it halts a little and the transfer starts at the next block.

Thank you very much,

-gshin