Information Technology Reference
In-Depth Information
Plan Phase
The Plan phase identifies the network requirements based on goals, facilities, and user
needs. This phase characterizes sites and assesses the network, performs a gap analysis
against best-practice architectures, and looks at the operational environment. A project
plan is developed to manage the tasks, responsible parties, milestones, and resources to do
the design and implementation. The project plan aligns with the scope, cost, and resource
parameters established with the original business requirements. This project plan is fol-
lowed (and updated) during all phases of the cycle.
Design Phase
The network design is developed based on the technical and business requirements ob-
tained from the previous phases. The network design specification is a comprehensive de-
tailed design that meets current business and technical requirements. It provides high
availability, reliability, security, scalability, and performance. The design includes network
diagrams and an equipment list. The project plan is updated with more granular informa-
tion for implementation. After the Design phase is approved, the Implement phase begins.
Implement Phase
New equipment is installed and configured, according to design specifications, in the Im-
plement phase. New devices replace or augment the existing infrastructure. The project
plan is followed during this phase. Planned network changes should be communicated in
change control meetings, with necessary approvals to proceed. Each step in the implemen-
tation should includes a description, detailed implementation guidelines, estimated time
to implement, rollback steps in case of a failure, and any additional reference information.
As changes are implemented they are also tested before moving to the Operate phase.
Operate Phase
The Operate phase maintains the network's day-to-day operational health. Operations in-
clude managing and monitoring network components, routing maintenance, managing up-
grades, managing performance, and identifying and correcting network faults. This phase
is the design's final test. During operation, network management stations should monitor
the network's general health and generate traps when certain thresholds are reached. Fault
detection, correction, and performance monitoring events provide initial data for the opti-
mize phase.
Optimize Phase
The Optimize phase involves proactive network management by identifying and resolving
issues before they affect the network. The Optimize phase may create a modified network
design if too many network problems arise, to improve performance issues, or to resolve
application issues. The requirement for a modified network design leads to the network
life cycle beginning.
Summary of PPDIOO Phases
Ta ble 1-7 summarizes the PPDIOO phases.
