Presentation is loading. Please wait.

Presentation is loading. Please wait.

CSG mini-Workshop Voice over IP Jim Jokl – Virginia Susan DeLellis – Harvard May, 2001.

Similar presentations


Presentation on theme: "CSG mini-Workshop Voice over IP Jim Jokl – Virginia Susan DeLellis – Harvard May, 2001."— Presentation transcript:

1 CSG mini-Workshop Voice over IP Jim Jokl – Virginia Susan DeLellis – Harvard May, 2001

2 VoIP Systems: Lots of definitions  PBX VoIP line or trunk card - A  Call path between IP phones via PBX  Initial releases by Lucent, NEC, others  PBX VoIP line or trunk cards - B  Call path between IP phones via LAN  Nortel, Siemens, others have systems  Most PBX manufacturers working towards this type of functionality  Major advantage: phone features

3 More VoIP System Definitions  LAN-based Systems  Call setup via LAN call processing server  Call path between all peripherals via LAN  Cisco Call Manager  Siemens HiPath Xpress  Nortel Business Communications Manager  Others  LAN-based systems generally limited  ACD, console, call center applications

4 Packet Voice: What is different? Traditional Phone SwitchVoice over IP (VoIP) Phone Switch Phone PSTN Campus Network Routers, hubs, switches PSTN Gateway Call Manager

5 Network Capacity for Multimedia Applications

6 Network Capacity for Packet Voice Services

7 Network Infrastructure for Voice over IP Support  Low latency  Low loss  Predictable packet arrival  High availability  Minimal capacity

8 Network Quality of Service (QoS)  Goal: provide better service for some  Build lots of network capacity  Layer 3 QoS  Layer 2 QoS

9 QoS: Useful for?  Have we seen the light?  Solving capacity problems?  Protect voice traffic?  Need a way to remap QoS parameters where traffic enters the network

10 Personal Computer IP Phone IP Phones and QoS  IP phone generates 802.1p CoS = 5 and IP precedence = 5  Switch in phone can clear PC’s QoS header settings  Phone and PC can be in different VLANs Switched Network Wall Jack

11 IP Telephones and Power  Powering options  Via Ethernet cable  Via wall power transformer  Phone power consumption  Tested Cisco and Nortel phones  Between 4 and 6.5 watts/phone  Large wiring closet  250 phones, 75% efficiency  Closet power: 400 Watts  Powering phones – no worse than 72 switch ports

12 My Other Wireless Phone

13 Wireless Data VoIP  Symbol NetVision Phone  H.323 on  But no DSSS yet (summer)  Spectralink NetLink Phone System  VoIP-based  Both FHSS and DSSS available  Proprietary adapter  integration  Killer App: b/PCS dual mode phone?

14 Wireless & QoS  Challenge: protect voice traffic  Wireless LANs low bandwidth  Easy to overload  SpectraLink Voice Priority (SVP)  Retransmission modification  Priority queuing in base station  Symbol  Similar capabilities  Standards?

15 Preparations at Virginia The Network  New backbone this summer  Layer 3 switching  IP Precedence  Wiring Closet  802.1p/Q  New edge switches will reclassify traffic  Policy management, multicast  Closet UPS and cooling work  Are these VoIP costs?

16 VoIP at Virginia  Initial application: toll bypass  AS-5300 Gateway – T1 to PBX  2600/3600/3810 at remote location  Analog interface to remote PBX  Added Cisco Call Manager  Couple dozen phones  Voice mail issues  Number portability

17 VoIP at Virginia  Siemens HiPath 5500  One dozen phones  PRI connection to Hicom PBX  CorNet features  Nortel Business Communications Manager  Planned for summer  Symbol?

18 Next Steps  Continue to prepare network for converged applications  Select a VoIP system for larger pilots  Harvest some low hanging fruit  Safe areas  Telecommuters  Wireless?  Solve the wired/wireless VoIP question  Continue to watch technology

19 Issues: Financial Model  Converged networks, especially VoIP, break most existing funding models  What to bill for  Wall outlet?  MAC Address?  IP phone or soft phone?  A tax based on headcount or NASF?  Central funding?


Download ppt "CSG mini-Workshop Voice over IP Jim Jokl – Virginia Susan DeLellis – Harvard May, 2001."

Similar presentations


Ads by Google