VoIP Basics A high level overview of Voice Over IP and it s

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VoIP Basics

• A high level overview of Voice Over IP and its
  place in the New Zealand Market.

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What is Voice Over IP?
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What is Voice Over IP?

• The packetisation and transport of classic public
  switched telephone system audio over an IP
  network.

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What is Voice Over IP?

• The packetisation and transport of classic public
  switched telephone system audio over an IP
  network.
• The analog audio stream is encoding in a digital
  format, with possible compression, and
  encapsulating it in IP for transport over your
  lan/wan or the public internet

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Categories of VoIP

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Categories of VoIP

• Amateur

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Categories of VoIP

• Amateur Skype, Microsoft Netmeeting, ohphone,
  gphone, Asterisk etc.

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Categories of VoIP

• Amateur Skype, Microsoft Netmeeting, ohphone,
  gphone, Asterisk etc.
• Enterprise

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Categories of VoIP

• Amateur Skype, Microsoft Netmeeting, ohphone,
  gphone, Asterisk etc.
• Enterprise Small IP phone deployments, IP PBX,
  Cisco Callmanager.

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Categories of VoIP

• Amateur Skype, Microsoft Netmeeting, ohphone,
  gphone, Asterisk etc.
• Enterprise Small IP phone deployments, IP PBX,
  Cisco Callmanager.
• ISP/Carrier

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Categories of VoIP

• Amateur Skype, Microsoft Netmeeting, ohphone,
  gphone, Asterisk etc.
• Enterprise Small IP phone deployments, IP PBX,
  Cisco Callmanager.
• ISP/Carrier Toll Bypass services, VOIP
  wholesale, using equipment by vendors such as
  Cisco, Lucent, Avaya, etc.

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Categories of VoIP

• Amateur Skype, Microsoft Netmeeting, ohphone,
  gphone, Asterisk etc.
• Enterprise Small IP phone deployments, IP PBX,
  Cisco Callmanager.
• ISP/Carrier Toll Bypass services, VOIP
  wholesale, using equipment by vendors such as
  Cisco, Lucent, Avaya, etc.
• Telco Grade

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Categories of VoIP

• Amateur Skype, Microsoft Netmeeting, ohphone,
  gphone, Asterisk etc.
• Enterprise Small IP phone deployments, IP PBX,
  Cisco Callmanager.
• ISP/Carrier Toll Bypass services, VOIP
  wholesale, using equipment by vendors such as
  Cisco, Lucent, Avaya, etc.
• Telco Grade Local service, Last mile delivery,
  total phone services, high dependability and
  availablility.

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How does it work?

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How does it work?

• VoIP is not a protocol. VoIP is a collection of
  protocols that allow for the encoding, transport
  and routing of audio calls over IP networks.

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How does it work?

• VoIP is not a protocol. VoIP is a collection of
  protocols that allow for the encoding, transport
  and routing of audio calls over IP networks.
• PSTN ? VoIP ? PSTN

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How does it work?

• VoIP is not a protocol. VoIP is a collection of
  protocols that allow for the encoding, transport
  and routing of audio calls over IP networks.
• PSTN ? VoIP ? PSTN
• Native VoIP ? PSTN

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How does it work?

• VoIP is not a protocol. VoIP is a collection of
  protocols and devices that allow for the
  encoding, transport and routing of audio calls
  over IP networks.
• PSTN ? VoIP ? PSTN
• Native VoIP ? PSTN
• Native VoIP ? Native VoIP

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The Guts

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The Guts

• RTP (Real-Time Transport Protocol)
• RTCP (Real-Time Control Protocol)
• RTP is a UDP stream with no intelligence for QOS
  or resource reservation
• Contains a packet number for detection of packet
  loss and re-sequencing of out of order packets.
• Unidirectional two streams in any call

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Control Protocols

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Control Protocols

• SIP Session Initiation Protocol.
• SIP is a textual based client server protocol.
  This makes debugging easy as its invite etc
  messages are human readable.

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Control Protocols

• SIP SessionInitiation Protocol.
• SIP is a textual based client/server protocol.
  This makes debugging easy as its invite etc
  messages are human readable.
• 200_INVITE
• Via SIP/2.0/UDP 10.30.60.205060
• From "Mr Anderson" ltsip099639951_at_10.30.60.20506
  0gttag1ACC.8D00
• To ltsip021326001_at_203.109.130.945060gttag359870
  F0-16CD
• Call-ID 00C0.95C9.5818.4013.1ACC.8D00_at_10.30.60.20
  
• CSeq 5257 ACK
• Content-Length 0
• Max-Forwards 70
• Contact sip099639951_at_10.30.60.205060

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Control Protocols

• MGCP Media Gateway Control Protocol.
• MGCP is a master/slave protocol where all the
  smarts resides in the gateway controller and not
  the gateway.

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Control Protocols

• H323

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Control Protocols

• H323 is a not a protocol itself but a suite of
  protocols including
• H.225
• H.245
• T38
• RAS and many more

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Control Protocols

• H323
• value H323_UserInformation
• h323-uu-pdu
• h323-message-body releaseComplete
• protocolIdentifier 0 0 8 2250 0 4
• callIdentifier
• guid '3E940C894E1311D8A33E919F0987C365
  'H
• h245Tunneling TRUE

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Control Protocols

• H323

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Control Protocols

• SIP
• MGCP
• H323
• Skinny Ciscos IP phone control protocol