The Nortel Ethernet Routing Switch 5510 models are 1 rack unit high next-generation stackable 10/100/1000 Mbps Ethernet Layer 3 routing switches designed to provide high-density Gigabit desktop connectivity to mid-size and large enterprise customers' wiring closets. Ethernet Routing Switch 5510-24T offers 24 10/100/1000BASE-T RJ-45 ports for desktop switching and two built-in SFP GBIC ports for uplink. Port 23 and Port 24 offer configuration flexibility as either a 10/100/1000 or a built-in SFP GBIC.