Information Technology Reference
In-Depth Information
Role (cop) versus Responsibility (crime fighting)
Figure A.7
Clarify roles and responsibilities.
Clarifying roles and responsibilities in matrix organizations is not easy
(Figure A.7). Dotted-line relationships can lead to vagueness in under-
standing one's roles and responsibilities. Job titles are supposed to reflect
roles and responsibilities but often they do not. Furthermore, new roles
evolve all the time. Examples include Web masters and security architects.
New roles are likely to be even less understood, and thus must have well-
defined responsibilities.
The question often asked is if you know your r ole, do you not
automatically know your responsibilities? Yes, if both are well defined.
The problems arise in assuming that they are.
Scale Up versus Scale Out
Scalability is the ability to increase or decrease computing capacity, while
delivering on value. Scalability is delivered through two methods: (1) scale
up and (2) scale out. It is important to realize that these are not mutually
exclusive choices. The scaling method used, scale up or scale out, depends
on the types of applications being used and on the type of functionality
needed. Hardware vendors have responded to the need for scalability
by creating multiprocessor machines.
, from a hardware
perspective, means increasing the number of processors, disk drives,
I/O channels, etc., all on a single machine.
Scaling up
, on the other hand,
means getting scalability using incremental hardware, not bigger hardware
itself. When one scales out, the size and speed of an individual machine
do not limit the total capacity of the network. Scale out, however, requires
the centralized management of the multiple hardware servers. Applications
such as transaction processing applications and CRM or ERP (customer
relationship management or enterprise resource planning) are architected
to perform best on a single, monolithic server requiring scale-up capabil-
ities. FTP servers, load balanced Web servers, VPN (virtual private network)
servers, and proxy servers are examples that benefit from scale-out tech-
nologies.
Scaling out
