> There's no harm in locking the port at 115200.  A lot of HTML
 > (in fact, most of it) is highly compressible, and would benefit
 > by having the higher speeds.
      Off to a bad start, and it gets even worse....  If the UARTs
aren't capable of the speed, locking at a higher speed can cause the port to 
drop bits.  This is most noticable on a file transfer using a protocol such 
as ZModem where you will see a lot of CRC errors and resends.  I say 
noticable because it will happen in other places, but you won't see it or the 
retransmission (such as TCP) is masked from the user.  Retransmissions will 
actually make the transfer rate slower than if you had locked at a lower 
rate.  If the hardware is capable, then in most cases there is no harm.
 > The faster transfers also reduce the CPU loading on your
 > computer because stuff gets transfered in fast bursts instead of
 > longer drawn-out transfers which tend to produce a lot more
 > interrupts.
      If the COM routines are using polling routines, a higher locked
rate will add CPU overhead while not necessarily increasing throughput.  
Polling is generally the way of older DOS apps, so this isn't much of a 
problem any longer.  But the UART will generate just as many interrupts on a 
fast transfer as a slow one, assuming the same amount of data is being 
transferred.  Interrupts are caused by the FIFOs becoming full and speed does 
not increase the size of these _hardware_ buffers.  16550 UARTs (and the 
derivitives) have 16 bit FIFO buffers.  There are cards available, such as 
the Hayes ISP(?), that have 1k buffers.
 > X2 connections.  I've seen X2 connections up to 51.3k, and I
 > certainly wouldn't even think of driving a modem running that
 > fast with a measly 57600bps link -- you'd be getting buffer
 > ovverruns if you even tried that (while you're surfing to a fast
 > site).  And buffer overruns are not pleasant things to deal with
 > (the only solution, usually, is to either raise the locked port
 > speed, or lower the speed of the modem itself).
      Buffer overruns are dealt with through hardware handshaking.
It's not a function of the locked port rate.  You should lock your port at a 
speed higher than your expected transfer rate.  It does little good to lock 
your port at 115k (although it probably won't hurt either) if your ISP is 
locking at 38.4k.  I personally lock my V34 Courier at 115k and occasionally 
see 110k transfers downloading newsgroups from Sprint.  But I have also dealt 
with an ISP that had VFC (it's been a while) modems on a 19.2 terminal 
server.  19.2k was all you were going to get....
-ll
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