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Understanding VoIP - 1

Understanding VoIP - 1. TO DOWNLOAD THIS PRESENTATION visit:. 1. Components, Standards and Architectures. The Big Picture. Major VoIP Components Terminals Packetized voice Soft switch Media server Gateway LAN WAN Standards and Protocols. Terminals. Packetized Voice.

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Understanding VoIP - 1

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  1. Understanding VoIP - 1 TO DOWNLOAD THIS PRESENTATION visit: http://ideapoolonline.wordpress.com

  2. 1. Components, Standards and Architectures • The Big Picture http://ideapoolonline.wordpress.com/category/hands-on/

  3. Major VoIP Components • Terminals • Packetized voice • Soft switch • Media server • Gateway • LAN • WAN • Standards and Protocols http://ideapoolonline.wordpress.com/category/hands-on/

  4. Terminals http://ideapoolonline.wordpress.com/category/hands-on/

  5. Packetized Voice http://ideapoolonline.wordpress.com/category/hands-on/

  6. Soft Switches – SIP Servers/Call Managers http://ideapoolonline.wordpress.com/category/hands-on/

  7. Softswitch: A programmable network switch that can process the signaling for all • types of packet protocols. • Also called SIP Server, SIP Proxy, Call Manager, VoIP Switch, Call Agent, IP Centrex, • Hosted PBX, User Agent, Gatekeeper (H.323). • According to International Softswitch Consortium, a softswitch should be able to: • Control connection services for a media gateway and / or native IP endpoints • Select processes that can be applied to a call. • Providing routing for a call within the network based on signaling and customer • database information. • Transfer the control of the call to another element . • Interface to and support management functions such as provisioning, fault, billing, • etc. • The switching technology in a softswitch is in software (hence the name) rather than • in the hardware as with traditional switching center technology. • This software programmability allows it to support IP telephony protocols • (H.323, SIP, MEGACO, etc.). • Examples of Softswitch: Asterisk, 3CX, Volcatel, etc. http://ideapoolonline.wordpress.com/category/hands-on/

  8. In Summary, the two main functions of a Softswitch are: • Terminal Control • Call Control http://ideapoolonline.wordpress.com/category/hands-on/

  9. Media Server or Content Server • A computer appliance, ranging from an enterprise class machine with a dedicated • software application providing contents such as voice, video, music, text, graphics. • Two interesting types of media/content: • Integrated Messaging • Video Server • Integrated Messaging • Voicemail, Email, Fax • Text-to-speech, speech-to-text • Web-style user interface • Video Server • Basic Cable • Video on Demand: Movie “rentals” • Pay-per-view, IPTV • PVR functionality • Game Server • Other Media • Web pages • Digital right management • Music • Google earth • Countless applications http://ideapoolonline.wordpress.com/category/hands-on/

  10. Gateways – Media Gateway • Gateways are Protocol Converters • Media Gateway converts traditional TDM • to RTP stream and vise versa. • TDM belongs to the PSTN world. • RTP belongs to the IP world. • Media and Signaling gateway could be a • single device or a separate device. http://ideapoolonline.wordpress.com/category/hands-on/

  11. Gateways – Signaling Gateway • Gateways are Protocol Converters • Signaling Gateway converts SIP to SS7 and • vice versa. • SIP belongs to the IP world. • SS7 belongs to the traditional PSTN world. http://ideapoolonline.wordpress.com/category/hands-on/

  12. LANs and WANs • LAN: In-building • Ethernet: 10 – 1000Mbps • Cabling: Cat5, Cat6e twisted pair • MAC Address • Power Over Ethernet • WAN: Between buildings • IP Addresses • Access: DSL, Cable, T1, Fiber, Microwave • Network Protocol: IP, Frame relay, ATM • Carrier Ethernet http://ideapoolonline.wordpress.com/category/hands-on/

  13. Key VoIP Standards • IETF • RFC 3261 SIP • RFC 2327 SDP • RFC 1889 RTP • RFC 0768 UDP • RFC 0791 IP • ITU-T • H.323: Historical • G.700: Voice coding • - G.711: 64kbps “PCM” • - Many others at lower rates • IEEE802.3 • TIA Cable Categories http://ideapoolonline.wordpress.com/category/hands-on/

  14. Where Are We Going? • Broadband IP Dial Tone. • IP-PSTN • Internet Protocol – Packet • Switch Telephone Network. • IP Packet to any other point > 1Mbps • Carrier Ethernet http://ideapoolonline.wordpress.com/category/hands-on/

  15. 2. VoIP Architectures and Implementation Choices • Computer-Computer VoIP Over The Internet • Requirements: • - Computer/Mobile Phone/PDA, …… • - Internet Access. • - Software: Skype, Nimbuzz, IM, ……. • - Directory, call setup/control. • - Sound card and headset or USB phone. • - Operating system: IP/UDP protocol • stack. • Considerations: • - Free (with internet connection) • - Interoperability: Standard? • - Less user-friendly than PSTN. • - Variable quality of voice http://ideapoolonline.wordpress.com/category/hands-on/

  16. Skype and IM • Proprietary technology • - Skype directory is based on Kazaa • - It uses P2P file sharing • - Good quality voice: Uses 15kbps codec • Works through NATs • - Communications encrypted • - Your computer could relay traffic • Good HMI – Human Machine Interface • Yahoo, Google, MSN, AOL, Nimbuzz. http://ideapoolonline.wordpress.com/category/hands-on/

  17. Computer to Phone • Broadband internet connection at one • end. • POTs at other end. • ITSP/VoIP Service provider in the • middle. • Variable voice quality. • E1 connection to circuit-switch PSTN. • Possibly ISP is different from the ITSP. • ITSP is located offshore. • Softphone required to connect to the • ITSP using SIP protocol. • Example of softphone: X-Lite, 3CX, etc. • Example of ITSP: Skype, Belgacom, • etc. http://ideapoolonline.wordpress.com/category/hands-on/

  18. Phone to Phone over the Internet • Broadband internet connection at one • end. • POTs at other end. • ITSP/VoIP Service provider in the • middle. • Variable voice quality. • E1 connection to circuit-switch PSTN. • Possibly, ISP is different from the ITSP. • ITSP is located offshore. • IP phone is required to connect to the • ITSP using SIP protocol. • Example of IP phone: Grandstream, • Cisco, Dlink, etc. • Example of ITSP: Skype, Belgacom, • etc. http://ideapoolonline.wordpress.com/category/hands-on/

  19. Phone to Phone over the Internet • ITSP either supplies the adapter or user • verifies compatible off-the-shelf adapter. • Broadband internet connection at one • end. • POTs at other end. • ITSP/VoIP Service provider in the • middle. • Variable voice quality. • E1 connection to circuit-switch PSTN. • Possibly, ISP is different from the ITSP. • ITSP is located offshore. • POTs connects to the adapter using the • FXS/FXO port. • The adapter acts as FX to VoIP gateway. • Example of ITSP: Skype, Belgacom, • etc. http://ideapoolonline.wordpress.com/category/hands-on/

  20. Managed-IP Telephone Service Provider • All IP end-to-end network. • Radio Access Network could be wireless • - (WiMAX, Wi-Fi, LTE), cable or fibre. • End-to-end Carrier Ethernet Network. • IP network QoS methods. • Voice quality is guarantee. • E1 connection to circuit switched PSTN. • ISP and ITSP – same company. • Provider connects with upstream ISP for • long distance call termination and www. • Provider supplies the adapter and • modem. • Example: ipNX http://ideapoolonline.wordpress.com/category/hands-on/

  21. 3. VoIPfor Businesses and Organizations • VoIP-Enabled PBX • PBX provides all VoIP functions. • Call management • Integrated gateway • Integrated voicemail • Supports VoIP and traditional phones • Phased implementation of VoIP • in-building. http://ideapoolonline.wordpress.com/category/hands-on/

  22. PBX Replacement • Softswitch • General purpose hardware • Proprietary software • Standards-based • Additional applications: • Messaging, conferencing, IVR, IM, • presence. • Availability and Survivability • Redundancy and failover • Distributed Call managers • Distributed call control tables • UPS in closets http://ideapoolonline.wordpress.com/category/hands-on/

  23. Hosted PBX • Softswitch at Service Provider • SIP messages over network • Customer configuration via web portal • IVR, ACD hosting too • Strategic Advantages • Professional implementation • Scalability, flexibility • Security, reliability • Financial advantages • Lease vs. buy: capital, maintenance • Reduce staffing • Disadvantages • Lack of control • Feature set? Capacity? http://ideapoolonline.wordpress.com/category/hands-on/

  24. IP Centrex • Hosted softswitch service from the Phone • Company • Huge Centrex customer base • Higher level of trust • Professionalism, longevity • Multilocation benefits • Uniform services, support • Bundled services • Access circuit plus telephony • Seamless services • Home-to-office VPN, telephony • Features and pricing • Per user, per month • Local number, DID • Desktop, web collaboration http://ideapoolonline.wordpress.com/category/hands-on/

  25. Open-sourced IP-PBX Software • Free code updated by users • Asterisk: One of the “Oldest” • IP PBX plus signaling server, • media gateway, analog/TDM PBX, IVR, • messaging server • Supported commercially • 30 – 50% cost of proprietary • Asterisk (Digium) • sipX, SIPfoundry (Pingtel) • Others: vovida, Freeswitch • Disadvantages • May be difficult to implement • Requires skilled technicians • Lack of management/support tools http://ideapoolonline.wordpress.com/category/hands-on/

  26. SO/HO IP Phone Features and Uses • Small / home office • All-in-one device • Fast processor, jitter buffer • Linux OS, browser, software • SIP, MGCP • Ethernet switch, PoE, PPPoE • Bluetooth • Router, DHCP, NAT, firewall • VPN, QoS support • Dialing features – dial by: • - Phone number, SIP address, • IP address, directory, voice recognition, • softkeys, presence/location notice,……. http://ideapoolonline.wordpress.com/category/hands-on/

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