Question

discuss what is Top Down and Bottom Up Tiered Lan Strategies. Discuss Which strategy will be preference and why?

Answer 1

Bottom-up Approach:
This begins with the physical layer and it goes up to the higher levels while its implementation. The switches, routers installed and LAN links are first created for individual section/ department or unit; then these whole units are interlinked to other such level network units.

Top-down Approach:
In this approach, the requirements of the organization are gathered first along with the technology needed. Then the design is created from the higher abstract level to down towards the individual units i.e. from top-level to bottom level. The services that are required are analyzed first and then the detailed structure is implemented up to the physical layer.

Which strategy will be preferred and why?

Here are the pros and cons of each:

	Bottom-Up	Top-Down
Pros	Less time consuming It needs more expertise and experience	It starts as per the actual requirement of the organization. Provides a bigger picture or a bird’s eye view of the whole design to the expert and the client
Cons	This might miss some of the design goals Probability of overall failure is high	Time taking process

It is though dependent on the requirement, availability of time and experts. But a Top-Down Approach is more reliable and hence preferable.