the ethernet routing switch 5500 series or (ers 5500) is a series of stackable, layer 3 switches used in computer networking. the ers 5000 was originally designed by nortel and is now manufactured by avaya. up to 8 ers 5000 series switches may be stacked in a 640 gbit/s fast stacking configuration. this switch was used as the access layer device for the 2010 winter olympics games. the 817 access switches supported 8782 voice-over-ip telephones.