Network lifecycle

As discussed in the previous section, the network is built for a specific purpose. Operating the network involves making changes to the network parameters, and sometimes design, to meet new business/application requirements, and finally the network is either replaced by a new design or incorporates a new technology. Since the network is dynamic, it is important to have a systematic approach based on the different phases of the network. Different approaches have been proposed by different vendors, but almost all of them are essentially overlapping and similar. In this section, we will cover Cisco's PPDIOO approach for network lifecycle, as it is the most comprehensive approach, and is a superset of other approaches within the scope of the network lifecycle. PPDIOO is an acronym for Prepare, Plan, Design, Implement, Operate, and Optimize.

Other forms of the lifecycle approach that are simplified versions of the PPDIOO approach are the Plan, Build, Manage (PBM) approach where some of the stages of the PPDIOO approach are combined into the three phases of the PBM approach.