Which table solution to use for a web application?

Question

Access rights

Requires a solution running on the platform MSSQL + IIS which:
1. Displays 1300 cells on the screen.
2. Allows multiple users to enter data into these cells at the same time. In this case, users enter data only in "their" cells. And they see the data entered into others.
3. Calculates the sums of cells after changing the focus from a cell that is included in the formula
3. With examples.