• 2 RJ-45 local area network (LAN) connectors, 1 RJ-45 T1 port for connecting the switch to a telephone company, 1 RJ-45 T1 monitor port for connecting test equipment, 1 RJ-21X port for punchdown block / patch panel / 12-port harmonica connector
• 2 loop start trunk ports (FXO) and 4 analog extension ports (FXS)
• Rack Mount Brackets are sold separately
• SIP trunking and extension support
• 1 DB-9, RS-232C maintenance port for serial communications