VoIP Technology Developments Net@EDU

  • Published on
    21-Aug-2015

  • View
    358

  • Download
    0

Embed Size (px)

Transcript

  1. 1. VoIP Technology Developments [email_address] Co-leaders: Jos A. Domnguez (University ofOregon) [email_address] http://ns.uoregon.edu/~jad/Net@EDU/
  2. 2. Several Uses for VoIP
    • Voice Trunk Replacement
    • End-user Appliances
    • Computer Telephony & VoIP
  3. 3. Elements of the Current Technology
    • Switching Devices (unPBX/IP PBX)
    • End-user Devices (IP Telephones, Ethernet Telephones, Computer Telephony Apps, Regular Analog/Digital Telephones)
    • Access Gateways (Analog/Digital)
    • Wireless VoIP
  4. 4. VoIP Technology (CODECs)
    • G.711 (PCM) 64Kbps (4.4 MOS)
    • G.721, G.723, G.726 (ADPCM) 16, 24, 32, 40 Kbps (4.2 MOS)
    • G.728 (LD-CELP) 16 Kbps (4.2 MOS)
    • G.729, G.729a(CS-ACELP) 8Kbps (4.2 MOS)
    • G.723.1 (CS-ACELP) 5.3Kbps (3.5 MOS), 6.3Kbps (3.98 MOS)
  5. 5. VoIP Technology (Delays)
    • Fixed Delay Components:
      • Propagation Delay
      • Serialization Delay
      • Processing Delay
    • Variable Delays:
      • Queuing Delay
  6. 6. VoIP Technology (Call Setup)
    • H.323 Standard (Video conferencing over Packet/Data Networks)
      • H.225
      • H.245
    • Real-Time Transport Protocol (RTP)/Real-Time Transport Control Protocol (RTCP)
    • Session Initiation Protocol (SIP)
    • Multimedia Gateway Control Protocol (MGCP)
  7. 7. VoIP Technology (QoS)
    • Dejitter Buffer
    • Type of Service (TOS)
    • Weighted Fair Queuing (WFQ)
    • Random Early Detection (RED)
    • Weighted RED (WRED)
    • Multilink PPP (MLPPP)
    • Resource Reservation Protocol (RSVP)
  8. 8. Concerns To Be Addressed
    • Powering for End-user Devices
    • Reliability
    • Troubleshooting VoIP Services
    • Access to Emergency Services and related issues (Liability)
  9. 9. What has changed?
    • IP Telephones powered by proprietary switching devices
    • Converters for Current devices
    • Some more layers of reliability have been added
    • New services added to IP PBXs and gateways
  10. 10. Things that we are still missing
    • Device location. Similar to cell phone triangulation. How about GPS?
    • Standardization for power provisioning
    • Plan for an open environment similar to the current data and voice networks
    • Management platforms
  11. 11. UO VoIP Services
    • Equipment:
      • Redundant IP/PBX Call Manager
      • Cisco Digital/Analog Gateways
      • Ciscos IP Telephones
    • Services Offered:
      • VoIP Trunks to Remote Sites
      • On Campus Mobility via IP Telephones
  12. 15. Tracking Technology Changes
    • Mailing Lists
      • IETFs IP Telephony WG ( [email_address] )
      • IETFs PSTN & Internet Internetworking WG ( [email_address] )
      • IETFs Media Gateway Control WG ( [email_address] )
      • Session Initiation Protocol WG ( [email_address] )
      • Other IETF WGs (SPIRITS, ENUM, RSVP, DIFFSERV, AVT, INTSERV)
      • Computer Telephony Newsletter ( [email_address] )
  13. 16. Tracking Technology Changes
    • Websites
      • Internet Technical Resources ( http://www.cs.columbia.edu/~hgs/internet )
      • Hello Direct ( http://www.phonezone.com )
      • Internet Telephony ( http://www.fokus.gmd.de/research/cc/glone/projects/ipt )
      • Computer Telephony ( http://www.telecomlibrary.com )
      • European Telecommunications Standards Institute ( http://www.etsi.org/tiphon )
      • Internet & Telecomms Convergence Consortium ( http://itel.mit.edu )
  14. 17. Tracking Technology Changes
    • Hardware Manufacturers
      • Cisco Systems ( http://www.cisco.com )
      • Lucent Technologies ( http://www.lucent.com )
      • 3Com ( http://www.3com.com )
      • Nortel Networks ( http://www.nortelnetworks.com )
      • Vocaltec ( http://www.vocaltec.com )
      • RadVision ( http://www.radvision.com )
  15. 18. Books in the market
    • IP Telephony (Bill Douskalis)
    • Voice over IP (???)
    • Voice over Data Networks (???)