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VoIP Technology Developments. Net@EDU Co-leaders: José A. Domínguez (University of Oregon) jad@ns.uoregon.edu http://ns.uoregon.edu/~jad/Net@EDU/. Several Uses for VoIP. Voice Trunk Replacement End-user Appliances Computer Telephony & VoIP.
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VoIP Technology Developments Net@EDU Co-leaders: José A. Domínguez (University of Oregon) jad@ns.uoregon.edu http://ns.uoregon.edu/~jad/Net@EDU/
Several Uses for VoIP • Voice Trunk Replacement • End-user Appliances • Computer Telephony & VoIP
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
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)
VoIP Technology (Delays) • Fixed Delay Components: • Propagation Delay • Serialization Delay • Processing Delay • Variable Delays: • Queuing Delay
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)
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)
Concerns To Be Addressed • Powering for End-user Devices • Reliability • Troubleshooting VoIP Services • Access to Emergency Services and related issues (Liability)
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
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
UO VoIP Services • Equipment: • Redundant IP/PBX Call Manager • Cisco Digital/Analog Gateways • Cisco’s IP Telephones • Services Offered: • VoIP Trunks to Remote Sites • On Campus Mobility via IP Telephones
Tracking Technology Changes • Mailing Lists • IETF’s IP Telephony WG (iptel@lists.research.bell-labs.com) • IETF’s PSTN & Internet Internetworking WG (pint@lists.research.bell-labs.com) • IETF’s Media Gateway Control WG (megaco@standards.nortelnetworks.com) • Session Initiation Protocol WG (sip@lists.research.bell-labs.com) • Other IETF WGs (SPIRITS, ENUM, RSVP, DIFFSERV, AVT, INTSERV) • Computer Telephony Newsletter (ctnewsletter@mf-newsletter.com)
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)
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)
Books in the market • IP Telephony (Bill Douskalis) • Voice over IP (???) • Voice over Data Networks (???)