Information Technology Reference
In-Depth Information
the evolving spectrum of user applications, malware defense, and sun-
dry other elements of the enterprise. An individual computer system may
serve many roles:
•
Server
—Any service that performs a task or presents data based on
requests from a client
•
Client
—Any system that consumes and/or presents data provided
by a system operating in a server role
•
Thin client
—Any system that serves only a presentation and input
role, without its own operating environment
Note:
Most systems will perform multiple roles, both hosting services and
consuming data from others. An individual system may even recursively
consume its own host services as a client.
The role of an individual hardware system may affect its update cycle,
depending on use, criticality, and other business issues such as service-
level agreement contracts. Thin client systems may be able to accept
updates without disrupting the remote client operating environment,
while updating a server could shut down entire operations until the pro-
cess is concluded. Care and planning is critical to ensure effective, timely
updates while avoiding or minimizing disruption of business.
Firmware
The most fundamental and lowest-frequency updates to hardware sys-
tems include updates to firmware. Firmware includes the internal instruc-
tion set used by a device for initiation and operation, often encoded in
nonvolatile storage. A common example of this is the basic input/output
system (BIOS) bootstrapping code used by a computer to start up, access
its long-term storage system, and begin loading its operating system. Firm-
ware refers to low-level operations of a device, separate from emerging
FLASH-based onboard storage used for immediate boot environments.
Firmware updates often require specialized standalone applications,
custom boot mechanisms, or other procedures whose function isolates the
update process from the business-as-usual functions of the device being
