The J2300E combines a personal computer with complete protocol analysis for WAN testing. It offers WAN and LAN protocol analysis capabilities, along with BERT testing, stimulus and response measurements, and statistical analysis capability. The J2300D monitors frame relay, ISDN, X.25, HDLC, SDLC, SNA async PPP and encapsulated LAN protocols running over the wide area network. Optional slide-in modules add test capability for ISDN BRI and PRI, DS-1/E1, DS-3/E3, and OC-3c/STM-1. Optional undercradles also add test capability for Ethernet, switched Ethernet, Fast Ethernet, Gigabit Ethernet, FDDI, Token-Ring, and OC-12c/STM-4c (622 Mbps ATM. Features include a 10.4-inch active-matrix screen, 1.4 MB floppy, 3 GB hard drive, and two PCMCIA slots.