I am not very familiar with Data Base, so my question is, which design is better?
If all the servers share a single DB, I don't have to design a protocol between the them. But I think it's not as efficient as the second one.
This is a ipphone system, the servers have to manage calls from phone to phone. If you have ever heard about SIP，you may know what I am talking about.
The servers are called Proxy Server and the DB are called Location Server where Proxy looks up for telephone information such as the ip address of callee phone.
Actually I want to write the system in perl and that's why I asked question here.
I would use MySQL as DB and Linux as OS for both proxy and location servers. 
+--------+   +--------+   +--------+
|        |   |        |   |        |
| Server1|-->| Data   |<--| Server2|
|        |   | Base   |   |        |
+--------+   +--------+   +--------+
                 ^
                 |
             +--------+
             |        |
             | Server3|
             |        |
             +--------+

+--------+   +--------+   +--------+   +--------+
|        |   |        |   |        |   |        |
| Server1|-->| Data   |   | Server2|-->| Data   |
|        |   | Base   |   |        |   | Base   |
+--------+   +--------+   +--------+   +--------+
    ^                         ^
    |                         |
    +-------------------------
                 |
                 V
             +--------+   +--------+
             |        |   |        |
             | Server3|-->| Data   |
             |        |   | Base   |
             +--------+   +--------+

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2006-06-11 Retitled by planetscape, as per Monastery guidelines

( keep:2 edit:16 reap:0 )

Original title: 'I have a design problem'

In reply to (OT) Database design question by ablmf

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