What is Network dimensioning ?

Network planning and design is an iterative process, which concerns the topological design, network-synthesis, and network-realization, and is aimed at guaranteeing that a new network meets the needs of both the subscriber and operator. Network planning and design is a very important process that must be performed before establishing a new communication network. 

Network Dimensioning is the main part of the preplanning phase. It is usually the first task to start the planning of a given cellular network.

Network dimensioning is done to find out the minimum capacity requirements that will still allow the Grade of service requirements to be met. That is to find out the minimum capacity requirements that accommodate busy hour traffic. Dimensioning involves planning for peak-hour traffic.

The dimensioning gives a preliminary network plan as an output, which is then supplemented in coverage and parameter planning phases to create a more detailed plan.

As basic inputs to dimensioning bellow mention criteria are taken.

1. coverage requirements , the signal level for outdoor, in- car and indoor with the probabilities (the geographical area to be covered)
2. quality requirements,         drop call rate, call blocking
3. frequency spectrum, number of channels, including information about possible needed guard bands (the frequency band to be used and frequency re-use)
4. subscriber information, number of users and growth figures
5. traffic per user, busy hour value (the estimated traffic in each region)

6. services
7. minimum requirements of power in each region and blocking

8. path loss

These inputs can be broadly divided into 3 categories:

·         Capacity related

·         Coverage related

·         Quality related

Giving the overall picture of the network and is used as a base for all planning activities network dimensioning play a vital part in System design. The main result is an estimation of the equipment necessary to meet capacity, coverage and quality requirements.[1]

In the dimensioning process the network’s topology, routing plan, traffic matrix, and Grade of service requirements are determined. Then this information is used to determine the maximum call handling capacity of the switches and the maximum number of channels required between the switches. This process is a little bit complex. Since the complexity of network dimensioning, typically specialized software tools are used.[1]

In dimensioning, the quality requirement is checked and significantly impact network reliability. By this, it has a huge impact on network users and the network operators. Since the Network Dimensioning involves planning for peak-hour traffic, it will help to increase the quality of service.

When considering the network operator network dimensioning plays a major part. Since the results of this activity essentially assist in the business planning and budget planning process for understanding the likely return on investment.

Since the results of the network dimensioning will significantly impact the network reliability and initial implementation cost, each parameter that is used in the dimensioning process must be thoroughly considered.[1]

Figure 1: Network dimensioning and planning process [1]

Reference:

[1] Radio Network Dimensioning and Planning for WiMAX Networks; Bharathi Upase, Mythri  Hunukumbure, Sunil Vadagama 2007

[2] Wikipedia      http://en.wikipedia.org/wiki/Network_planning_and_design#Dimensioning

[3] Network Dimensioning Esteeming QoS Parameters’ Independences; Emiliya Saranova 2006