WD  WDXE2500JBN 250 GB Net Center Fast 7,200 RPM, 8MB cache hard drive 10/100 Base-T Ethernet Connection Allows RAID 1 mirroring for real time data backup when a drive is added to a USB port Dynamic host configuration protocol (DHCP) client for automatic assignment of TCP/IP addresses Includes two hot swappable USB 2.0 host ports for printers and additional USB external drives