# Zone of Flexibility

The optimal solution in a network design study often shows clear boundaries. This customer will be served by that resource, and that customer by another resource, even though the customers are close. This is perfectly fine for strategic decisions, but for more operational decisions this is too rigid. In case you run out of capacity in the operational situation, you want to know where your flexibility is. One form of flexibility is customers that can be served from another DC, Producer, or Supplier than the assigned one in the optimal solution because they are not that far away from customers that are already served by that DC, Producer, or Supplier. Those customers will be included in the Zone of Flexibility.

The image below helps to illustrate the customers that are in that zone. This image only identifies two of them, but there are of course more:

Customer x is in the Zone of Flexibility (by-product) if there exists another customer y, where customer y is supplied by resource/supplier r, while customer x is not supplied by resource/supplier r and customer y is close to customer "x".

Here you can see, two big circles around two customer nodes. The size of the circle is determined by both the value of Relative Distance Threshold and Absolute Distance Threshold that are shown on this page. Any customer that is within this circle, but not supplied by this resource is in the Zone of Flexibility. In this case, the two nodes that have an arrow point to them.

The Zone of Flexibility page looks like this:

## Relative/Absolute Distance Threshold

As explained above, the Relative and Absolute Distance Threshold is used to indicate how far a customer in the zone of flexibility can be from another to still be considered close enough (and therefore included in the zone of flexibility). The distance between x and y must be less than Relative Distance Threshold percentage of the distance between y and r or the distance between x and y must be less than Absolute Distance Threshold.

## Customers in the zone

This shows the number of customer locations that are in the Zone of Flexibility.

## Zone of flexibility Map and Legend

There are several different types of nodes. The Legend side panel explains what type each node is. The different nodes have the following interpretation:

• DC/Supplier/Production: These are the different types of nodes from which the products are distributed. We have chosen to give them the same color, to prevent an overload of different colors in one map.

• Customers with Demand: These are the customers that have demand for the selected products.

• Customers without Demand: These are the customers that have no demand for the selected products, but they have demand for other products.

• Zone of Flexibility: These are the customer that is in the Zone of Flexibility for the selected products.

## Product Filter Side Panel

The Zone of Flexibility is determined by product, each product has its own set of customers that are in the Zone of Flexibility. If all resources have the same capabilities, there will be few differences. Otherwise, there will be different zones for different products. Using the product filter you can select which products you want to see the zone of flexibility. (See Filtering in Network Design for more)