TWNIC RMS Update 16 th APNIC NIR SIG TWNIC Sheng Wei Kuo [email protected] Aug, 2003.
Next-Generation Communications Services: Issues and Opportunities John C Klensin, Ph.D. TWNIC...
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![Page 1: Next-Generation Communications Services: Issues and Opportunities John C Klensin, Ph.D. TWNIC Conference, 2004 March.](https://reader036.fdocuments.in/reader036/viewer/2022062421/56649e4e5503460f94b45724/html5/thumbnails/1.jpg)
Next-Generation Communications Services: Issues and Opportunities
John C Klensin, Ph.D.
TWNIC Conference, 2004 March
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2004.03.31 2
Looking Two Steps Ahead
• Talk is less aboutWhat is happening today or
what one should do next
• But, instead, about What to start looking at now for the steps after
the next one.
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2004.03.31 3
New Services or Simulation of Old Ones in New Medium
• Is the Internet a good telephone?– VoIP in closed networks
• Equipment savings ?• Still simulating SS7 ?
– Internet Telephony• Service quality, customer support, and
expectations• Economics and tariff arbitrage
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2004.03.31 4
Internet Telephony as a Substitution Service
• Dubious long-term economics
• Good short-term
• Very good for equipment providers
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2004.03.31 5
Tariff Arbitrage
• Very good short-term business• In the long term, one of several things happens
– Regulators impose comparable tariffs on new activities
– Tariffs are abolished, reducing or eliminating price advantage
– New activities are prohibited– New activities are ignored; old, tariffed, way of doing
things disappears
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2004.03.31 6
Terminal Signaling Capability as a Defining Characteristic
• Service models determined by twelve buttons (or worse)
• Consequences– Smart Central Switches– Intelligent Network– Menus and VRUs to increase call setup
bandwidth
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2004.03.31 7
The History of Distance Communications
• Low bandwidth – High speed– Signal fires, drums, telegraph, telex– Telephone ?
• High bandwidth – Low speed– Packets of letters carried by horse or coach– Bags of letters carried by train– Tapes in the back of an automobile– Fax or other images of paper ?
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2004.03.31 8
Reviewing “Convergence”
• Carry the torch onto the coach ?
• Load the horse onto the train ?
• Tapping on the telephone handset ?
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2004.03.31 9
The Actual Pattern
• Parallel use until
One technology drops off
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2004.03.31 10
Advanced Services in the PSTN Paradigm
• “Integrated Messaging”– Voice, voicemail, fax, pager to one phone
number– Remote pickup and intercept
• Call forwarding and similar routing
• The Instant Messaging problem
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2004.03.31 11
What Are You Trying to Reach
• Surrogate for a copper pair leading to a specific terminal device?
• A person or function?
Almost always the second
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2004.03.31 12
Specifying a Target
• Preferred medium ?
• Person or alternative ?
• How important ?
• Interruption levels and tracking/ forwarding
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2004.03.31 13
Permitting a Source
• Receiving a connection should be a negotiation…
• Do you want to be reached? By the caller?
• With what priority ? How much are you willing to be followed around?
• What do you think of the caller’s priorities?
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2004.03.31 14
Example: Phone call with forwarding and roaming
• Colleague places a call to US “office number” at 2PM.
• Phone rings at 3 am in Singapore• Obvious questions…
– Would it have been placed if destination and time were known?
– Should it be received without knowing its importance?– How does one guess at time of recipient when
country and city codes are meaningless?
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2004.03.31 15
Example: Whom am I calling?
• Number reaches a terminal or surrogate. People may be widely distributed.
• Long VRU menus seem to be our best solution, but cannot be the right answer.
• So– Call person or function, not a number– If we are to number people for convenience,
E.164 phone numbers are probably the wrong model
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2004.03.31 16
Can This be Done in the PSTN?
• Maybe
• Big scaling problem, high complexity
• Very difficult authentication problems– Current “four digit PIN” strategy in many
countries not good enough– Limit to setting from “home” phone provides
poor service.
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2004.03.31 17
ENUM itself may be the wrong model
• E.164 is not only tied to phone system semantics but to complex regulatory politics
• While the routing environment tied to E.164 is implemented by bilateral agreements, ENUM creates the first global telephony regulation opportunity for ITU.
• Should it have been– Number.CityCode.3166-country-code.enum… ?– For example: 23411313.2.tw.enum… or even
23411313.2.886.enum… ?
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2004.03.31 18
Who Needs “Internet Telephony”?
• Internet → PSTN– Yes, but for how long and at what rates?
• Internet → Internet– Not needed; use NAPTR records with names
• PSTN → Internet– Not for Central Office switches: better ways– Not for dual mode phones: Internet → Internet
or POTs → POTs devices– Smart-routing PBX switches? Maybe.
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2004.03.31 19
Networks: Central Control and Edge Control
• Edge-based networks permit distribution of control functions– “My server”, “my agent”… not tied to CO
switch– Different people/ organizations can get
different functions– Lots of competitive business opportunities
• Avoid both “one size fits all” and option-complexity problems
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2004.03.31 20
A Different Communications Model – Initiator
• Specifies preferences– Person or function to be reached– Preferred/ ranked contact medium
• Simultaneous voice, voicemail, fax, email, assistant,…
– Priority/ importance– Conditions
• E.g., “don’t interrupt if…”
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2004.03.31 21
A Different Communications Model – Receiver
• Specifies rules for people/ groups/ defaults– Preferred/ ranked contact medium
• Simultaneous voice, voicemail, fax, email, assistant,…
– Assessment of priority/ importance statements• More priority from some people than they specify• Less for others
– Relationship between• Derived priority and• Acceptable medium
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2004.03.31 22
Generalization
• Extensions are almost trivial for– Multiparty communications
“conference calls” and group discussions
– Multimedia connectionsImages, text, sound, interactive remote whiteboards
– Asynchronous and semi-asynchronous communications
Email, fax, instant messages, “push” voicemail
• The special case– Two party, not prearranged, fully synchronous, audio-
only,…
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2004.03.31 23
Some Lessons from Instant Messaging
• Is being interrupted a good thing?– Maybe better than by the telephone– More choices:
• Identification of caller, not calling number• Ability to delay response somewhat, not pure real-time
• Controlled access to interrupt– Need more than
• Available or not• Friend or not
• How to divert to email, or…
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2004.03.31 24
Could we do this?
• Technology basically exists• Changing styles of thinking
moving away from “make it look like a telephone”
may be harder
• Designing a rule-specifying system that is• Sophisticated enough to be useful• Simple enough for consumers to use
– Is not trivial. But not impossible either.
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2004.03.31 25
What Next?
• If we build it, will anyone come?
• How bad does – information overload– Interruption overload
need to get before we do something real about it?