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IP Telephony Applications for Handhelds

IP Telephony Applications for Handhelds Keith Weiner DiamondWare Presentation goals Look closely at cellular, cordless phones Why computer telephony, why PDA, why now? PDA telephony technologies Engineering and market issues Projections and statistics Demo PDA telephony is not cellular

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IP Telephony Applications for Handhelds

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  1. IP Telephony Applications for Handhelds Keith Weiner DiamondWare

  2. Presentation goals • Look closely at cellular, cordless phones • Why computer telephony, why PDA, why now? • PDA telephony technologies • Engineering and market issues • Projections and statistics • Demo

  3. PDA telephony is not cellular • Those are cool Devices! • Samsung I300, Nokia Communicator, Handspring Treo • It’s a cool Application! • Combine two functions into 1 device • …But different.

  4. Cellular advantages • Nationwide WAN coverage • Roaming at 90mph • Low capex • Free or near-free • But no advantage within enterprise space

  5. Cellular cellularness • Monthly bills • High latency • “Hello, Over?” • Poor voice quality • Especially “transcoding” between carriers • Doesn’t work well in some buildings • Fabs, dense high-rises

  6. But everyone uses it • On the road • At lunch • In coworkers’ offices • Out of habit, even at their own desks! • Give out one number: the mobile • Mgmt. losing control and predictability • PSTN minutes negotiated in bulk

  7. Cordless phones • Expensive • Nortel T7406 $525 MSRP • Trapped by system vendor • Or live with analog port limitations • Another extra device • Forget it when you wander down the hall • One more gadget on your belt

  8. Ok, why computer telephony? • Why IP? • Converged networks • LAN, voice, wireless • Why a software-based telephone? • More usable • Presence • Availability

  9. We need to do better

  10. IP telephony for handhelds • PDA is becoming mission-critical • With decent CPU, audio chip, wireless NIC • Leverage it with a softphone • Inherently cheaper than dedicated phone • Cheaper to build and to upgrade • More powerful

  11. PDA VoIP advantages • Same as for desktop and laptop • Features • Address book • Recording • Presence • Play tunes without worry, ring can interrupt • Better voice quality (wideband) • Plus mobility

  12. Applications • Workforce communication in factory floors, warehouses, campuses • Walking over to the next office • Desktop phone replacement • Take it with you to Starbucks, airports, hotels and other hotspots

  13. Why wireless PDA? I • PDA deployment is growing • Wireless IP deployment is growing • Leverage them • Network convergence • Wired LAN • Telephony • Wireless

  14. Why wireless PDA? II • See list of conference attendees • Control your availability as seen by others • Whiteboard, Text (IM) • N-way calling • “Line” is never busy • Why limit to just 3-way?

  15. Softphone architecture I • IP socket support • Call control protocol • SIP or H.323 • Realtime audio transport (i.e. RTP) • Audio is broken into packets

  16. Softphone architecture II • Microphone capture • Process (e.g. echo, AGC) • Compress (e.g. G.711, G.729) • Wrap in an RTP header • Send to remote host

  17. Softphone architecture III • Network receive • Decompress • Process (e.g. dejitter, echo) • Send to audio chip

  18. What does it take? • Real computer (PocketPC, Zaurus, Webpad), with a real audio chip • Sorry Palm • Headphones • Wireless network, typically 802.11b • 802.11a gets cheaper (under twice 802.11b) • For PSTN calls, IP-PBX gateway

  19. 802.11 issues I • Bandwidth Constrained • 802.11b has only 11 Mbps • 802.11a has 54 Mbps • 802.11g has 54 Mbps also, but 2.4GHz • QoS • Cannot add segments, like w/wired LANs • “Sto dow..oading so I .c.. ta..k” • No standard yet

  20. 802.11 issues II • Airwave contention • NICs hidden from each other • RTS/CTS • RF Interference • 802.11b uses 2.4ghz, not great spectrum • 802.11a uses 5ghz, better spectrum

  21. 802.11 issues III • Security • Encryption (wired equivalent privacy) is a toy • “Warchalking” • MAC address filtering helps, somewhat • Access controllers • Built-in authentication • Connect to auth server (e.g. RADIUS, LDAP) • Painless subnet roaming

  22. VoIP issues • For IP calls to or from the outside • NAT • Firewall • Proxy • Some solutions • Server outside the gate (e.g. Ridgeway) • UPnP NAT

  23. PocketPC issues • Speaker and mic coupled • Headphones req’d • Mic-less headphones • 50 lashes with a wet noodle • Compute-limited for echo cancellation • Battery life • Powered down when idle • But can’t receive calls!

  24. Market issues • Inside your space, build what you want • Not many outside hotspots yet • Roaming problem • Dynamic routing • Mesh Networks • Mass acceptance req’d for business model • 200 users at airport gate—holy QoS, Batman!

  25. Marketscape • Existing products • Avaya, support for their PBX • VTGO, supports Cisco Call Manager • SoftJoy Labs, supports H.323 and SIP • In Development • DiamondWare, SIP, lowest latency • Telesym, connects to 3rd party PBXs • Others

  26. Resistance is futile! • (You will be assimilated) • The PDA is/will be mission-critical • You will carry it for many reasons • Why not use it for the voice function? • No worse off than before • Within wireless zones, much better

  27. Necessary next steps • Ubiquitous Wireless access points • Outside the enterprise • Answers on the business side • 30 free minutes with every cup at Starbucks? • By the hour at airports? • 1000 minutes/month like cellular? • By the day at hotels?

  28. My projections • Wideband (16khz) audio will win people • PDAs will be carried everywhere • PDAs will be net.connected when possible • PDAs will be used as phones when net.connected • SIP makes follow-me easy • PoE (power over ethernet) icing on cake

  29. Statistics • 100% of communications shows I’ve attended, past 12 months • 5.3M NICs and 1.8M WAPs sold in 20011 • $400/$100 avg. cost, enterprise WAP/NIC • 44 “hotspots” in Arizona2 1Gartner 280211hotspots.com

  30. About me • CEO of DiamondWare • Developers of low-latency voice software • mailto:keith@dw.com • cell: (602) 478-9275 • SIP:keith@dw.com (coming soon)

  31. Wideband Audio • “Your confirmation number is FS5BP3TD” • Try that on a phone • Worse yet, a cell

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