> However here in Darkest Africa :-) most of us(clients and me) cannot afford
> leased lines or permanent connections.
> If I consider option 2 do you have examples/demos that demonstrate how to
> cache data temporarily. How to work with an unconnected dataset that
> contains data. Also any design tips will be appreciated. I have never done
> something like this so I dont know what components to use. I suspect that
> there is most probably such a demo in ibo already.

I use frame relay to link sites, but here in the UK we have found that we just
can't rely on it, so there are lots of little 'fixes' to make things work.

What I have done is set up the system to keep copies of the database at each
site, so when frame relay falls over they can carry on working. Only informaton
relevent to a site is copied from the main server, so, for example, only the
customer details that the site needs will exist in the copy. There is a field
that has a timestamp for the last update, so that changes can be monitored. The
stock at each site is maintained locally, and only when necessary do you then
need to dial the main server. If an enquiry needs 'global' information, then
the main server is accessed directly, and at the same time, any 'cached'
information is checked. In this way you make full use of the minimum connection
charge, without haveing to dial all the time.

You need to establish what information will be more stable longterm, such as
contact details, addresses, and old orders. And what is transitory, such as
current stock that is not at a local outlet. You will be suprised how much can
be done without actually dialing, and when you do, you just add a check for
local records with a timestamp older than the central copy, and download them.

Does this fit in with the way your sites will be working?

--
Lester Caine
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L.S.Caine Electronic Services