Re: Three-Tier Client Server

jgreene_at_aol.com (Jgreene) wrote:
>In article <1995May18.144208.4496_at_nosc.mil>, mvergara_at_sctcorp.com (Michael
>P. Vergara) says:
>>
>>My boss asked me today about this. I have never heard of 'Three-Tier
>>Client/Server' architecture. Am I that far out of it? Can anyone
>>shed some light on this topic?
>
>There is also an Article in the May 29 Information Week that discusses
>this subject. I have run into a few of these environments. Basically,
>you take the two-tier architecture that you would see in
>Powerbuilder-Oracle environments (client does the display and much of the
>processing, while the server provides RDBMS services) and add additional
>servers to take some of the thinking away from the client and some of the
>thinking away from the database server. What you have left is a client
>that is resonsible for input, graphics, output, comminucations and some
>applicaitons processing. The appliecations server does a lot of the rules
>processing and coordinating services. Finally the data servers store the
>data and allow you to retrieve it. There may be vendors who disagree with
>my synopsis (i.e. they designed their products differently), but that is
>my quick and dirty understanding of the subject. Hope it helps.

Oracle calls this either a "three tier client/server environment", "client/server/server", or more usually a "co-operative server environment".

There are several advantages to this kind of an architecture, chief among them being that you can shield the client, which is quite often a PC, from having to run more than one networking protocol. You can also eliminate the need for having the client know anything about two phase commit.

A client can simply connect to one database and that database can then connect to anything else required through the use of database links, views, synonyms, etc. Oracle's Transparent Gateways are all built on this type of an architecture. Actually, pretty much anything you do with Oracle supports this type of connectivity nicely.

Hope this helps. Received on Sun May 28 1995 - 00:00:00 CEST