Angular 2: Cannot find name 'Subscription'
in angular 6 and angular 7
import { Subscription } from 'rxjs';
You have to import it like this:
import { Subscription } from 'rxjs';
ORIGINAL ANSWER
import { Subscription } from 'rxjs/Subscription';
Take a look here: https://angular.io/docs/ts/latest/guide/router.html and there are several plunker's linked in that documentation.