My application has one master page and 5 child page to load inside it.

**Contents of Master Page**:  

1. UserControl (Drop Down)  

2. 5 Main Tabs (Child Page loads for every Main Tab Click).

Initially when application loads, all the data is loaded for Drop Down and one of the child page .

so whenever a click on one of the main tab link (its href),so whole page gets reloaded and data will be loaded again for all the controls of the page.

so , i don't want to load the data for my drop down again and again on every Main Tab Click.

As i am working on legacy application every thing is coded, i can't use Update panel for this as a solution because it requires lot of code change.

so i am looking for a solution to keep my Drop Down Data static across all the tabs, even if it refreshes for every tab click.