Custom column sorting not working

[Arti3DPlayer]

For example i have a custom column:

{
    label: "RUNNING or STOPPED",
    editable: false,
    cell: Backgrid.Cell.extend({
        render: function () {
              if (this.model.get('is_running') == 1) {
                  this.$el.text('Running');
              } else {
                 this.$el.text('Stopped');
              }
             return this;
        }
    })
},

And sorting for this column(when we click on title) is not working