Transcript Presence
Presence in Mobile VoIP networks
Alex Shneyderman
Senior Product Manager
Cisco-dynamicsoft
[email protected]
973-980-9177
Agenda
Role of presence
Presence definitions and current trends
Technology behind current presence solutions
Applying presence solutions to specific operator’s needs
Conclusion
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What is presence?
In a pervasively mobile society, access to information is no longer
determined by the availability of communication media but rather by
the subscriber’s willingness and ability to communicate.
Operators can determine if a subscriber is both willing and able to
communicate by using technology which can discover and distribute
the real-time subscriber state information
Presence is defined as a collection of real-time data describing the
ability and willingness of a user to communicate across specific media
and devices.
Presence deployment architectures can roughly be divided into two
categories:
Network Presence used by the network to facilitate call control
Client Presence used by user devices to enable users or client applications to
make communications decisions directly.
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Standardizing Presence
Presence is being standardized by a number of standards groups
such as IETF, 3GPP, and PAM forum.
SIMPLE
Simple is developed by IETF and Backed by many industry leaders including Cisco and
Microsoft.
SIMPLE provides a set of extensions to SIP to cover presence requirements not yet
addressed by SIP location server by introducing new message extensions PUBLISH,
SUBSCRIBE, and NOTIFY.
OMA IMPS
Open Mobile Alliance Instant Messaging and Presence Services workgroup is backed
by Major handset manufacturers Nokia, Ericsson and Motorola
Creates a set of specifications for propagating instant messages and presence
information between a mobile handset and a server in the mobile network
PAM
Presence and Availability Management standard created by PAM Forum to standardize
Presence concepts independent of applications and networks. PAM specifications are
not protocols but rather a set of APIs
PAM Is a de-facto presence standard of ETSI and 3GPP
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What problems can be addressed with
Presence?
Limitations of existing services
Lack of Information about the user
Availability alerts
voice mail
PTT unconfirmed indicator
Mobile Instant Messaging accuracy
conferencing
Who (user identity)?
Where (geographical location)?
When (user preferences and availability)?
How (device capability, available communications media)?
Why (policies, permissions, eligibility, necessity, information type)?
Lack of Interesting New Services
Location/presence
Relationship management
PTT call handling enhancements
Presence enhanced service request routing
Presence enhanced address books and directory services
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The Network Effect
Value and Accuracy
of Presence
The Value Of Presence Increases
Exponentially with the Richness of the
Data It Has Access to
User State
In a meeting,
outside, driving,
geo-location
The Natural Evolution Of The Carrier
Network Is Toward A SubscriberAware Network Which Centralizes
Storage and Distribution of Presence
Data
The Carrier Who Offers the Best
Real-time Presence to Users and
Other Applications Has Tremendous
Leverage
Application
In a call, playing a game,
device capabilities
Connection
IP Address, MIN, URI
Registration
Online/offline
No Presence
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Practical Presence
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Presence Solution components
Presence Server
A Presence Server designed for discovery, management and propagation of presence
information.
Location Server or SIP registrar used to support routing of SIP requests
Presence triggers
SS7 gateway used to gather connectivity and call state from the carrier's HLR.
AAA presence gateway used to collect network connectivity state from the carrier's AAA server
IM gateway for desktop IM presence
Presence client
BREW/Palm OS/Windows-based client and app capable of displaying and collecting presence
Presence applications
Missed Call Service
Call Back Alert
Presence-enhanced PTT
etc
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Presence Server
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Presence Server Functionality
Real-time subscriber
information
Information unique to the
user/handset relationship
PresencePrivacy
Server
Policy
Presenceenhanced
call control
Real-Time Network
information
Information unique to the
operator/handset relationship
Real-Time Application
information
Presenceenhanced
applications
Information unique to the
applications
Rich Presence
Discovery capability
Subscriber information
to other networks,
applications and clients
Is Stored and managed
in a Single Location
Is Distributed As
Needed
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Presence Server Deployment in VoIP networks
Access Network
Presence Sources
Infrastructure
Presence-enabled
VoIP Applications
HLR
IP PBX
GMLC
Presence
Server
SMSC
Cellular
with PTT
AAA/RADIUS
Push-to-Talk
Applications
Smart forwarding
SIP/SIMPLE
Instant
Conferencing
Application Server
SIP
Servers
Calendar
Enhanced call
routing
Clients
VoWi-Fi
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Key Features of a Presence Server
Presence discovery and distribution
Receives presence information from multiple sources
Combines presence from multiple sources based on the collected state
Collects presence through on-demand querying, periodic polling, and triggering
Supports multiple protocols for interfacing to external data sources
Propagates Presence Data out to All Authorized Subscribers and Applications
through Standards-based Interfaces
Strong policy and authorization control
Users/providers can specify who sees their presence
Users/providers can specify what is seen, and when it is seen
Controls what applications and users get access to presence
Controls which applications can push presence into the Presence Server
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Presence Discovery
Presence Server must be capable of discovering network presence
with various degrees of accuracy from all real-time subscriber state
information sources available in the network
Examples of Presence sources
SS7 presence
interrogation
periodic polling
triggering
AAA presence
SIP Presence
SIP registrar updates via SIPMPLE SUBSCRIBE/NOTIFY
Client Presence
Client publish
User defined presence
Calendar presence
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Presence Client
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Getting Presence To The Handset
Lessons Learned about VoIP Presence
Wireless VoIP presence is not the same as desktop VoIP presence
Wireless presence may in fact prove to offer richer user information
Must Minimize Over-the-Air Bandwidth
Minimal representation of information
Minimal information necessary
Minimal update frequency (zero when not needed)
Information Must Be real-time to be useful
Updates should be frequent when it is known the user will look at the status
Retrieval must be very fast
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Typical Presence Client
typical functionality:
Support for three basic availability classes: available, not available, shadow mode
Works with contacts from the existing phonebook stored on the handset
Support for both push and pull presence retrieval options (one-click retrieval and automatic update)
Support for one click contact calling capability
Yahoo IM-style dynamic presence icons
Client examples
Quallcom Dynamic directory
Verizon Push-to-Talk
Gaim client
Followap client
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Real Life Presence solutions
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Presence-Enhanced PTT Contact List
Adding Presence to PTT/VoIP contact list address user problem
of lack of information about the called party
Do they have a data session?
Are they registered for PTT?
Are they in a voice call?
Are they in-fact registered?
Do they even want to be called?
This information can be made available in various forms
Basic presence
Premium presence
Fetch presence state for contacts when user opens address book
Fetch only presence for the contact to which call is about to be made
Continuously update presence for selected contacts or the whole list in user-defined
intervals
Add user-defined presence status overriding network presence
Presence-enhanced contact list benefits
User benefits
Availability: Users can see status of others prior to communication
Reachability: Users can understand whether the target device is available for a call
Operator benefits
Additional billable application
Better user experience and differentiation
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PTT Unconfirmed Indication
Defined: Unconfirmed Indication: The PoC Server confirms readiness
to receive media before it has received confirmation from downstream
elements of readiness to receive media.
Needed because the “wake up delay” of dormant mobile telephony data
connections may add several seconds to the time required for the request to
complete.
The caller receives a confirmation tone BEFORE the of the receiver’s reachability
confirmation is received. The caller begins speaking and then interrupted by a
failure tone up to 14 seconds after they begin speaking
Happens when the PoC Server does not have enough information about the
availability of the recipient’s mobile device prior to call setup attempt
Unconfirmed indicator can be addressed by presence
Is the mobile active and reachable from a network perspective?
Does user have an active registration for the PoC service?
Is the users on a circuit phone call?
Do users have an active data session that supports PoC?
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Presence Improves Reliability of Unconfirmed Indication
Push-to-Talk
Server
Pushto-Talk
client
AAA
1
PDSN
4
SIP Proxy
SIP Proxy
PDSN
Pushto-Talk
client
2
Caller
HLR
3
MSC
Called
party
Presence
Server
1. Caller initiates a Push-to-Talk session
2. The PTT server sends a query to the Presence server in parallel with placing a call to the target
subscriber. Alternatively Presence Server maybe set up to constantly update PTT server with presence
information received from AAA Server or HLR
3. Presence Server queries the HLR and AAA Server for circuit call state information and sends called
party status to the PTT Server
4. Caller is only allowed to start transmitting voice to the MG if the called party is both REGISTERED and
Not on a 2G phone call. In the event that the called party is available, the buffered media is sent on to
their mobile device
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Missed Call Summary
ALERT called party that they received a
call when they were not available
Alex’s phone is
currently off, not in
network coverage.
Anita
Alex
_____
Missed Call____
Alex
10:23am
Anita Called –
973-555-1212
Options
When he turns his
phone on, he receives
a Missed Call Alert
Back
Allows Subscribers to Get a Summary of the Calls Missed when their phone was off or out
of coverage and caller did not leave a message
Missed call summary can be propagated via an SMS Message
MCS system can be Integrated with the Operator Voice Mail System
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New Applications – Call Back Alert
ALERT caller when the called party is
most likely reachable
Anita
Alex’s phone is
currently off.
“<Alex> cannot take your
call, press ‘1’ to receive a
text notification when he
becomes available and
you can also leave a
message”
Alex
_____iAlert______
10:30am
When he turns his phone
on, Anita receives the alert
or a dial-out
Alex is now reachable
Anita
Options
Back
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Conclusion
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Presence Classified
Presence
Network-based
Client-based
Presence detection
Presence aggregation
Presence distribution
Presence reporting
Presence requesting
Presence processing
Presence Applications
Resolve
Network
limitations
Create
New
Services
Enhance
Existing
Services
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Presence Deployment conclusions
Presence is not easy to sell
The benefits and the business case of presence are not fully understood by the
market more attractive
In the current telecom environment presence is more likely to be deployed to
address the limitations or enhance the existing systems rather then to create new
apps
Presence is more likely to be considered when offered as a feature of an existing
system
Examples of existing systems which may benefit from presence
VoIP-based PTT systems
Voice mail
Unconfirmed indicator
PTT client
Call Back Alert
Missed call service
Enterprise conferencing system
Presence-enhanced dynamic directory
Presence-enhanced VoIP conferencing
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Thank you
Contact:
Alex Shneyderman
Senior Product Manager
[email protected]
+1.973.952.5073