Apr 18, 2023 1

PCS in Telephony &Intelligent Network

versusICEBERG

Bhaskaran RamanNetwork Reading Group

Friday, Feb 5 1999

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Outline

• Personal Communication Services (PCS) in telephony

• IN architecture (very high level)• Relation to ICEBERG

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Personal Communication Services

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What is PCS?

• Vague term - not well defined• Personalised voice, data, image,

video• Three types of mobility:

– Terminal mobility (network level)– Personal mobility (across access devices

and networks)– Service mobility (see the same personal

service profile)

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What is PCS?

• PCS also talks about customization & security

• From telephone network background– service providers and subscribers– trusted network– dumb end-points

• Interworking is required between service providers

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The Networks

• Fixed Networks (POTS)• Cellular (e.g. GSM)• Digital Cordless (e.g. DECT)• Wireless data (e.g. GPRS)• Satellite

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PCS in Fixed Networks

• Call Screening• Personal Numbering (Hotline)• Profile Management• Call Forwarding• Automatic Callback

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UPT

• Subscriber has personal number• Billing and service profiles based

on the personal number• Service availability across different

(fixed) networks

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GSM

• Does not provide full PCS• Handles terminal mobility well• No complete integration with

cordless• SIM: provides another kind of

mobility

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UMTS, IMT2000, FPLMTS

• Networks to provide PCS• UMTS - ETSI effort• IMT2000 (previously FPLMTS) - ITU

effort• To provide global mobility & digital

data services

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IN Architecture

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What is IN?

• Separation of spec, creation & control of services from physical switching networks– Evolved from a world where the only

service available was switching– Present from day 1 in IP

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AIN History

• Idea of Stored Program Control– for ease of deploying services

• IN/1 - 800 calling, call waiting• IN/2 - additional services• IN/1+ - simplification of IN/2• MVI (Multi-Vendor Interactions)• AIN

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What does it define?

• Technical capabilities for SS7 components– SCP (Service Control Point)– SSP (Service Switching Point)– IP (Intelligent Peripheral)

• Planes of abstraction

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TCP/IP

• IN defines Points-In-Call (PICs) at SSPs– off-hook– digit-called– did not answer...

• TCP (Trigger Check Point) for each PIC

• FE (Functional Entity) at SCP/IP

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An Example AIN Service

• Portable Speed Calling List• Dial *55, PIN, Speed Calling

Number– How is it speedy ?

• AIN switch causes a trigger• Sends message to SCP

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Example Service Continued...

• SCP invokes SLP (Stored Logic Program)

• SCP verified PIN• Completes call

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Feature Interaction

• How do complicated features have unforeseen interactions?

• Examples:– Universal Call Forwarding: paying toll– Voice mail ‘#’ sign???– OCP, TCP, CFU

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ICEBERG

• In addition to PCS:– Network transparency across

voice/data/paging networks– Service transformations (e.g. E911)– Service handoff– User preference management

(Universal Inbox)– Any-to-Any data transformations

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ICEBERG

• Anyone can deploy services (flexible service infrastructure)

• Motivation for IN:– “…rapidly engineer new revenue

producing services, in response to market opportunities….Ultimately, service creation, or at least service customization can be extended to subscribers”

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Discussion

• Why did they hack away?• SS7, UPT, IN -- are they still hacks?• “Billing and security aspects are studied

in standardization bodies (ETSI and ITU), but work on these subjects is not very advanced because of the complexity involved for network operators to protect their interests”