Rationale for MySQL Cluster

Second chapter of "MySQL Cluster 7.5 inside and out".

When I started developing the ideas for NDB Cluster in my Ph.D studies
about 25 years ago, the first thing I did was to perform a very thorough
study of the requirements.

At that time I participated in a European Research for UMTS. UMTS was
later marketed as 3G. My part of this big study group of more than 100
researchers was to simulate the network behaviour. We used the
protocols developed by other groups to see what the load would be on
the various nodes in the telecom network.

I was mostly interested in the load it contributed to the network databases.
Through these studies and also by studying the AXE system developed
in Ericsson I got a very good picture of the requirements on a DBMS
to be used for future telecom services.

In parallel with this I also studied a number of other areas such as
multimedia email servers, news-on-demand servers, genealogy
servers that would be other popular services in the telecom network.

In the above chapter I go through how those requirements was turned
into requirements on predictable response times, availability requirements,
throughput requirements and so forth.

In particular how the requirement led to a model that divided the Data
Server functionality (NDB data nodes) and the Query Server
functionality (MySQL Server nodes).

Also how predictable response times are achieved by building on ideas
from the AXE architecture developed in Ericsson.