IP-enabled PBX (Internet Protocol-enabled Private Branch eXchange)

A PBX that couples

VoIP (Voice over Internet Protocol) onto a conventional PBX based on time division multiplexing (TDM). The intelligent IP phones can take the form of either hardphones or softphones that connect either over a switched Ethernet LAN. The LAN-attached data terminals interconnect as usual. The IP

phones connect to the PBX through an Ethernet port on a line card that includes an IP gateway that resolves the interface issues between the TDM bus and the switched Ethernet LAN that supports VoIP.

Calls between the LAN-attached IP phones are conducted on a peer-to-peer basis using their LAN

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• packet layer protocol (PLP)
• Packet over SONET (POS)
• packet switch
• PACS (Personal Access Communications Services)
• padding
• PAD (Packet Assembler/Disassembler)
• page
• pager
• pager identification number (PID)
• pager identification number (PID)
• paging system
• paging system
• pair-gain
• Palo Alto Research Center (PARC)
• PAL (Phase Alternate Line)
• PAM (Pulse Amplitude Modulation)
• PAMS (Perceptual Analysis Measurement System)
• panel switch
• PAN (Personal Area Network)
• PANS (Pretty Advanced New Services, Pretty Advanced Network Services, Peculiar And
• paper
• paperless office
• paperless office
• PAP (Password Authentication Protocol)
• parabolic antenna