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From: MTG <mtg2@xxxxxxxxxxxxx>
> since it seems pretty apparent that bmi is not very interested in
> supporting its clients and only giving excuses does anyone have a good
> fast and accurate vendor and their phone number that can provide futures
> data in real time???
I will do a long explanation here ...
in fact its a reply I did some time ago to someone else about bmi.
If the info I have is incorrect - please post it so everybody on the list
will know.
the uplink of bmi to satellite is 19.2K compressed.
the downlink is the same.
assume 2:1 compression you get bandwidth of 38.4K
that is 38.4K bps - bit per second.
38.4 x 1000 / 8 = 4800 byte per sec approx.
MSFT has 20000 tick on average per day nowadays,
it was 3000 to 8000 a few yrs back.
20000 / 390 min = 51 trades per min. approx. 1 trade per sec.
each trade need at least 15 bytes for the price, volume, exchange, etc.
4800 byte / 15 byte = 320 records per sec <- top most limit.
if they can do a 10 bytes rec then 4800 / 10 = 480 rec per sec top.
so, lets see, we got more than 1000 stocks that act like MSFT
everyday NOW!!!
so the bmi sat feed is flooded with 1000 - 320 = 700 extra
recs per sec that it cannot handle.
so, ticks are dropped, trades are summarized, and quotes are of course
delayed. plus, bmi is stupid enough to broadcast news headlines, so the
problem is even worst. summarization of trades = no broadcast of side ticks
for futures, and for stocks, the tradevol are added up for the same
traded price to save bandwidth.
even with higher compression and better encoding technique
bmi is still short at least a double of its bandwidth to successfully
handle the full us mkt without problems. what they need is the fundamental
bandwidth widen at the satellite up/down link level.
bmi can't tell us to switch to someone else :)
and switching to dbc is no use as their technology is about the same ...
There are 3 feeds now that can handle the cuurent us mkt load -
bloomberg, pc quote sat, and sp comstock sat. they all are 128K to 256K
speed compressed.
so the current mkt condition is almost nothing to their bandwidth.
-Lawrence Chan
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