Replication over satelite connection.

Hi everybody, we are designing an application for ships, and I want to replicate data between the ships and a home office. TCP/IP communication is not possible, but we have a e-mail based system for transferring files.
What is the best solution? Is it possible to have the publisher/subscriber to leave a file, and then let the e-mail system transfer the file and then later the subscriber/publisher can pick up the file and do the merge?
Any ideas?
Thanx, Kjetil
Kjetil,
this is not directly possible in the replication setup. You might want to
use DTS to import the file into a database then in the DTS package. Setup
replication between this staging database and your central system and you
can initiate replication locally.
HTH,
Paul Ibison
|||Thanks, this is what I tried to say to my boss. But how can this be implemented? Should I use merge replication or transactional replication.
In my home office, I will need a 'copy' of the ship database, in the first stage 9 ships.
Is it possible to block the database in the ships for updates while the replication process is running?
Or should I use transactional replication, will I then need a 'proxy database' at each ship and one for each ship in the home office. Is it possible to implement conflict resolution methods that guarantee the same result at all sites always?
The amount of data over the satellite link (64k) is an issue, so it is important to send only the changes.
Do you think I'm on track? Is it possible to implement.
Kjetil
|||Kjso,
as you need inserts updates and deletes to be replicated over the internet,
you are essentially coding what MS developers may well be creating in SQL
2005 :-). This is not straightforward at all (to say the least). You might
want to use triggers on each table which write an audit of changes to your
audit table(s). These audit table changes are then sent over the link to a
central server where they are applied to the central database. In my opinion
this is only going to be feasible at the central server if you have
partitioned data; dealing with conflicts will make this too difficult. Then
sending only the changes required back to the other subscribers is not
simple. You say that you want only changes, but a 'snapshot' would be more
straightforward.
HTH,
Paul Ibison