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Asterisk PBX

Asterisk Linux based PBX - introduction

Asterisk has got to be one of the finds of the year for me, this is an excellent open source FREE piece of software that can turn your linux box into a PBX.

Asterisk Features

Asterisk offers both classical PBX functionality and advanced features, and interoperates with traditional standards-based telephony systems and Voice over IP systems.  Asterisk offers the features one would expect of a large proprietary PBX system such as Voicemail, Conference Bridging, Call Queuing, and Call Detail Records.

Telephony Services:
  • Voicemail System
    • Password Protected
    • Separate Away and Unavailable Messages
    • Default or Custom Messages
    • Multiple Mail Folders
    • Web Interface for Voicemail Checking
    • E-mail notification of Voicemail
    • Voicemail Forwarding
    • Visual Message Waiting Indicator
    • Message Waiting Stutter Dialtone
  • Auto Attendant
  • Interactive Voice Response
  • Overhead Paging
  • Flexible Extension Logic
    • Multiple Line Extensions
    • Multi-Layered Access Control
    • Direct Inward System Access
  • Directory Listing
  • Conference Bridging
    • Unlimited Conference Rooms
    • Access Control
  • Call Queuing
  • ADSI Menu System
    • Support for Advanced Telephony Features
    • PBX Driven Visual Menu Systems
    • Visual Notification of Voicemail
  • Call Detail Records
  • Local Call Agents
  • Remote Call Agents
  • Protocol Bridging
    • Provides seamless integration of technologies
    • Offers a unified set of services to users regardless of connection type
    • Allows interoperability of VoIP systems
Call Features:
  • Music on Hold
  • Music on Transfer
    • Flexible mp3 based system
    • Volume Control
    • Random Play
    • Linear Play
  • Call Waiting
  • Caller ID
  • Caller ID Blocking
  • Caller ID on Call Waiting
  • Call Forward on Busy
  • Call Forward on No Answer
  • Call Forward Variable
  • Call Transfer
  • Call Parking
  • Call Retrieval
  • Remote Call Pickup
  • Do Not Disturb
  • Scalability:
  • TDMoE
    • Allows Direct Connection of Asterisk PBX
    • Offers Zero Latency
    • Uses Commodity Ethernet Hardware
  • Voice over IP
    • Allows for Integration of Physically Separate Installations
    • Uses commonly deployed data connections
    • Allows a unified dialplan across multiple offices
Voice over IP Interoperability:

Asterisk provides transparent bridging between Voice over IP protocols and traditional telephony equipment.  In addition, Asterisk can transfer calls from one system to another via the Inter Asterisk Exchange protocol.

  • Inter-Asterisk Exchange (IAX)
  • H.323
  • Session Initiation Protocol (SIP)
  • Media Gateway Control Protocol (MGCP)
Traditional Telephony Interoperability
  • Robbed Bit Signaling Types
    • FXS and FXO
    • Loopstart
    • Groundstart
    • Kewlstart
    • E&M
    • E&M Wink
    • Feature Group D
  • PRI Protocols
    • 4ESS
    • Lucent 5E
    • DMS100
    • National ISDN2
    • EuroISDN
    • BRI (ISDN4Linux)
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