views/gui/ngXosViews/serviceTopology/src/templates/topology_canvas.tpl.html

<div class="subscriber-select">
    Select a subscriber:
    <select class="form-control" ng-options="s as s.name for s in vm.subscribers" ng-model="vm.selectedSubscriber" ng-change="vm.getServiceChain(vm.selectedSubscriber)">
        <option value="">Select a subscriber...</option>
    </select>
</div>