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When SIP Sucks (and what to do about it)

When SIP Sucks (and what to do about it). This talk was originally titled “How VOIP is going down the tubes” but a lot of people misinterpreted what I was going to talk about. (including me). Michael Täht CTO, Transconf.Net http://the-edge.blogspot.com/. Caveats.

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When SIP Sucks (and what to do about it)

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  1. When SIP Sucks(and what to do about it) • This talk was originally titled “How VOIP is going down the tubes” but a lot of people misinterpreted what I was going to talk about. • (including me) Michael Täht CTO, Transconf.Net http://the-edge.blogspot.com/

  2. Caveats • This talk is highly opinionated and does not in any way reflect the position of my employer. • This talk has been known to cure birth defects in new products and small children. • This talk contains positions that are not strictly true but are included solely to get a laugh. • YOU HAVE BEEN WARNED.

  3. A short history of voice protocols • Shouting across the canyon • Industrial Revolution - Tin Cans and String • Watson, Can you hear me? What? • [80 years of added complexity elided] • H323 – Nice try! • SIP – When Elephants fight, the grass suffers • IAX2 – New kid on the block

  4. The core problems facing SIP • NAT • Outgoing Bandwidth • Static Ips/DNS/firewalls • Codec Interoperability • Complexity • Ourselves

  5. NAT & Firewall Hell • How many of you have had a sip phone get through a firewall the first time? • NAT “Solutions” are a 70 Billion dollar INDUSTRY. It's a problem that needs to be solved – permanently! • How many of you have had two sip phones get through a firewall the first time?

  6. Bandwidth Boondoggle • Original Design of America's Cable Network: • Enough bandwidth to have a buy button, no more! • Bullet dodged: It turned out you need enough return bandwidth for ACK packets. If it weren't for TCP/IP ACKs, however... we'd have no voice capability at all at home. • Outside the US, bandwidth is less of a problem • US wired phones are in decline (down 8% in the last year alone) • Third World – Skipping wired entirely and going to wireless.

  7. Asymmetric Bandwidth

  8. The real story for multiple phones is your outbound bandwidth LOTS 6 calls (barely) 3 calls (barely) 2 calls (barely)

  9. First Circle of Interoperable Pain • Not enough outbound bandwidth – well, use a better codec than ulaw. • “Better codecs” like speex and g729 rarely negotiate correctly and rarely carry dtmf well • OK, so use out of band signalling to solve that • With out of band signalling – great, now you have to synthesize DTMF for endpoints that need it, for correct durations and inband/rfc2833. What's a correct duration? • And round and round you go

  10. What you need is a codec that uses less bandwidth! • Which one? • GSM – makes “digital quality” sound like sarcasm. • G729 – need a license! • G722 – Pretty good actually • Speex – Got enough cpu? A device that supports it? Great. What settings are you using? • None of these pass DTMF worth a darn.

  11. Weapons of Mass Distraction • ISPs selling: • Incoming rather than outgoing bandwidth • Dynamic rather than static ip • DNS – what's that? • Phone companies bragging about: • Least number of call drops • You know, there's something I really care about – a lot...

  12. Quality! • Reliable Calling and Presence • Sound Quality • 8khz is the pits • I miss the sound of cymbals, the crack of a snare, the upper octaves of a piano... • And voice recognition – the holy grail of the Star Trek generation – really needs more than 8khz to work well.

  13. Skype • Oh, yea, skype • If it wasn't for Skype I'd probably be satisfied with SIP's problems.

  14. Stuff that keeps me awake at night • Regulation • E911 – With a softphone on a laptop – nobody knows where you are – and I like it that way! • Still, 911 is a valuable service – is there another way? • Network Neutrality • Patents • Servers in vulnerable locations

  15. Stuff that drives me crazy • Bugs • Code I can't fix • Code I can't get fixed • Firmware updates on hard phones • Look, all you are doing is copying a couple files • Please standardize! • Slow boot times in general

  16. All the problems are being addressed... • But the problems are different • US – Not a lot of bandwidth • EUROPE – Skype Rulze • ASIA – Need IPv6 • THIRD WORLD - Not enough of anything • And they aren't happening fast enough! • Who's to blame? • OURSELVES

  17. PART 2(a short break to let the room air out) • What else is driving you nuts about the industry?

  18. How to connect people together(and make a little money) • The purpose of the phone network is to connect two or more people together. • Anything that does less than that is not acceptable • Other services besides basic connectivity are • Great example – tellme.com – provides 411 and other advanced services (and they interconnect with fwd.net!) • Presence • Web integration • Etc

  19. But getting two people to talk remains difficult... • How to compete – CO-operate! • Metcalfe's law – the value of a network increases as to the square of the number of users. • Get out of the media loop and switch • Just switching calls requires nearly zero bandwidth • (virbiage did a great job at this with firefly/iax – why not iaxtel? You? Me?)

  20. And getting two new people to talk, nearly impossible. • In a few years, 10 million kids are going to have a hand powered laptop to learn with -via the One Laptop Per Child project • How are they going to talk to each other? • I'd like it to be over some voip technology • But what? (iax over IPv6?) • How to accelerate progress elsewhere?

  21. Change the conversation • It's subversive, but every so often, late at night, I'll write a letter like this from a random email account: • Dear <RANDOM ISP> • I would like to communicate with my friends in the Far East, and I'd like to have a real Ipv6 address to use here in the states. Can I get one from you? • The responses I get have been gradually getting more informed. But most are laughable.

  22. If you think letter writing doesn't help... • In late 1993 I wrote something like this... • Dear Mr. Gates: • I am writing to ask that you incorporate some sort of clean TCP/ip functionality into Windows. Trumpet winsock is too kludgy and requires too much effort....

  23. Engaging Metcalfe's Law • Value of connecting together 100 million people • 3+ Billion dollars – Skype • Metcalfe's Law: The value of a network is equal to the square of the number of users • In this room there are ~100 people • Together we could make quite a phone company • TURN TO YOUR NEIGHBOR - SHAKE HANDS and SAY – I'd like to PEER WITH YOU. • ... and get a piece of that action!

  24. Get Connected • Ask – “How'd you like to interoperate?” • E164.ORG • ENUM • DUNDI • Or INVENT YOUR OWN... • BUT First - CHOOSE TO INTEROPERATE

  25. Blogging as broadcasting • I used to write letters, still do, now I blog. • Google reads my stuff, I'm pretty happy about that. • 18 months ago I blogged about a new interesting market for voip (conference call transcription) • This year – three companies are doing it – and I don't have to!

  26. Explore Alternatives • VOIP is an AND proposition • CONNECT PEOPLE TOGETHER • (and make a little money) • See also - Freeswitch: http://www.freeswitch.org • Even VOCAL and GNU gatekeeper have some interesting ideas • So do commercial products like Cisco's CallManager

  27. PARTICIPATE • The internet is not TV – services like • voip-info.org • irc.freenode.org • the IRC channels #asterisk #asterisk-dev • Mailing lists • Asterisk-devel and asterisk-biz • DEPEND ON YOU.

  28. Use the Experimental Services • IAX2 • IAXTEL • Free World Dialup • E.164.ORG • DUNDI • JINGLE • Etc

  29. Lastly, keep having fun • I keep finding people doing cool stuff... Dave Troy - who is using asterisk to control the roomba - and he has a mobile phone and a camera tied to it! Someone I met outside doing a slackware version of asterisk that appealed to 14 year olds Simon Ditner - bringing old text adventures back to life Brian Capouch - hacking openwrt to bring wireless broadband to rural areas David Rowe - Building hardware for the heck of it and, at least for me - hearing about this sort of stuff - keeps me plugging away at VOIP! Thanks for listening! Michael Täht CTO, Transconf.Net http://the-edge.blogspot.com/ 10/26/06

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