multimedia messaging - krnet · · 2012-05-09ims – naming / addressing / routing (2) public...

Multimedia Messaging

KRnet 2003

Jun-Won Lee E-mail : [email protected]

KRnet 2003 - Multimedia Messaging 2

목 차

메시징 서비스

메시징 관련 표준

IMS – Naming / Addressing / Routing

IMS – Presence Service

IMS – Group Management

Push-to-Talk 서비스 개요

Push-to-Talk 서비스 업계 동향

Push-to-Talk 서비스 구조 및 GUI 샘플


메시징 서비스 (1)

SMS Perceived as being a real time service

Real time delivery cannot guaranteed

MMS

Based on SMTP(non real time)

Forward msg to the mail box not to the recipient

All media types available : text, images, audio, video

Instant

Messaging

Real time / Primarily text-based / presence services

May store msg if recipient unavailable (SMS-like)

Chat Private/Public chat rooms

One send text to a central point, distribute to others

E-mail Most popular method of messaging available today

Similar delivery mechanism as MMS (non real time)


메시징 서비스 (2)

Immediate Delivery Messaging • In (near) real time

• Prior awareness of the availability of the recipient(s)

1) Pager Mode Messaging

Messages are Independent of each other

SIP MESSAGE method

2) Session-Mode Messaging

Message Session Relay Protocol (MSRP) : Mechanism for

transmitting session-mode messages with minimalist relay

support

E.g., chat room

Deferred Delivery Messaging • Reliable transfer of message guaranteed


메시징 관련 표준 (1)

IETF • IMPP(Instant Messaging and Presence Protocol) WG

Goal : define a standard protocol so that independently developed applications of instant messaging and presence can interoperate

RFC2779 : a minimal set of requirements for IM and Presence

RFC2778 : a model of presence and instant messaging

• SIP(Session Initiation Protocol) WG

RFC3265, Session Initiation Protocol (SIP)-Specific Event Notification

RFC3428, Session Initiation Protocol (SIP) Extension for Instant Messaging

• SIMPLE(SIP for Instant Messaging and Presence Leveraging Extensions) WG

draft-ietf-simple-presence-10.txt, A Presence Event Package for the Session Initiation Protocol (SIP)



(앞에서 계속)

• MSN messenger has support for SIP

• AOL will support SIMPLE for interoperability with other IM

applications

Wireless Village • Now part of Open Mobile Alliance(OMA)

• IMPS(Instant Messaging and Presence Service)

Now version 1.2 available

WAP and HTTP based

Only for wireless now

No seamless interoperation with other IM applications

• Started working on IMPS 2.0

Considering CPIM and SIMPLE support



3GPP IMS(IP Multimedia Subsystem) • Including the elements necessary to support IP Multimedia(IM)

services

• Based on the IETF defined SIP protocol

• Purpose

Convergence of, and access to voice, video, messaging, data

and web-based technologies for the wireless user

Combine the growth of the Internet with the growth in mobile

communications

• ISC (IMS Service Control Interface)

Interface between S-CSCF and service platforms

Protocol to be used on ISC shall be SIP(RFC3261)


IMS – Naming / Addressing / Routing (1)

Identification of users • Private user identities

NAI(network access identifier) : RFC2486

• Public user identities

SIP URL or TEL URL format

Routing of signaling within the IMS • Use SIP URIs or AbsoluteURI(RFC 2396)

• E.164 format shall not be used

Session request based on E.164 format require conversion into

SIP URL for internal IMS usage

E.164 address to SIP-URI resolution • Using ENUM DNS translation mechanism

• If failed, the session may be routed to the PSTN


IMS – Naming / Addressing / Routing (2)

Public service identities • Identify services

presence, messaging, conferencing, etc.

E.g sip:[email protected]

• Users establish a session to the „public service identity‟ to be able to

send and receive messages from other session participants

• Hosted by AS(application servers)

• IM CN shall be able to route IMS messages using „public service

identities‟


IMS – Presence Service (1)

Presence

CS domain IMS

PS domain

Internet

Visited networks

Other networks

Home Environment

Voice services

Data services

Supplementary services

Multimedia services

Presence-enhanced

Ab

str

ac

t en

titi

es



Standard Documents • TS 22.141 v6.2.0, Presence service; Stage 1

• TS 23.141 v6.2.0, Presence service; Architecture and functional description

Presence Service • Targeting Wireless-enhanced version (e.g., using location

information)

• Provides ability for the home network to manage presence information of a user‟s device, service or service media even whilst roaming

Presentity • Representing a user

• Representing an abstract service or application

Road traffic information, sports results, news headlines



User Status Available

Not a vailable

Discreet

Invisib le

Location City

Coun try

Mark’s Presentity

Access Rules

My name is Mark and I am supported by the presence service. I have a presentity which represents me, and I am the principal of my presentity. As the principal, I supply

information to my presentity.

My presentity consists of information (describing my ability and willingness to communicate) and access rules (describing how my presence information

may be accessed).

Principal and presence information as a presentity



Presence Service Model

PRESENCE SERVICE

PRESENTITY

FETCHER

Fetcher requests the current

value of some Presentity’s

presence information from the

Presence Service

SUBSCRIBED-

WATCHER

Subscribed-watcher is a Watcher that

requests notification of (future) changes

in some Presentity’s presence

information from the Presence Service

POLLER

A Poller is a Fetcher that

requests the current value of

some Presentity’s presence

information from the Presence

Service on a regular basis.

WATCHER



Presence Information

PRESENCE INFORMATION

.

.

.

PRESENCE TUPLE

STATUS

COMMUNICATION ADDRESS

OTHER MARKUP

PRESENCE TUPLE

OTHER PRESENCE MARKUP


STATUS

Contact address

Communication means

PRESENCE TUPLE

STATUS


OTHER MARKUP

PRESENCE TUPLE

OTHER PRESENCE MARKUP


STATUS

Contact address

Communication means



Item Explanation Example Values

Status Current condition of the

device or service represented

by the presence tuple

Open, closed, online,

offline, busy, away, do

not disturb, etc.

Item Explanation Example Values

Communication

means

A method whereby

communication can take

place

Service type(e.g.

telephony, SMS),

media type(e.g., audio,

text, video, multimedia

messaging service etc.

Status A specific point of contact via

some communications means

E.164, URI, inbox

address, etc.

Presence Information



A user’s presence information obtained from 1) The user

2) Information from supplied by network entities

3) Inforrmation supplied by elements external to the home network

(Reference Architecture 참조)



Reference Architecture

Interfaces Ph, Pi, Pc, Pg, Pk and Pl are based on existing R5

procedures e.g. CAMEL, MAP, CAP, RADIUS, ISC, Cx, Sh.

PeuPresence User agent

(Presence information

provided by the user)

Presence Network agent

(Presence information

provided by the network)

Pen

Pi

MSC Server

/VLRSGSN GMLC

Ph Pc Pg

Presence suppliers

Presence server

(home network)

Presentity

Presence Proxy

Watcher

Presence Proxy

Watcher

applications

HSS

(HLR)Pw

Pw

Pw

Px

GGSNS-CSCFHSS/HLR

Pk Pl

Presence External agent (Presence

information provided by elements

outside the provider’s network)

Pex



Watcher

application

Px = Cx

P-CSCF S-CSCF

I-CSCF

S-CSCFPresence

Server

Presentity Presence

Proxy

HSS

Pw = ISC

Pw =Mw

Watcher Presence Proxy

Pw = Gm

Application

Server

(Presence

List)

ISC

Watcher

application

Pw = ISC

Relationship of Presence Proxies with IMS entities



A Party Network B Party Network

A WA - A

Watcher

Presence

Proxy

1. Presence enquiry for B


2


10a. B party

status sent to

IPP

4.

11. B’s presence status to A

8, 9

Presentity

Presence

Proxy

6. Presentity Presence Proxy

derives address of B’s presence

server


PS - B HLR/HSS

10b. B party status sent

to Watcher Presence

Proxy

10c. B party

status sent to

WA-A



Charging Requirements (not exhaustive) • Watcher Presence Proxy provides charging information for

Presence enquiry or subscription and subsequent notifications

• Presence Server provides charging information for

publishing presence information

Subscription to watcher lists

…


IMS - Group Management (1)

IMS Group Management • 3GPP TS 22.250 (Release 6)

• Provides possibility to manage network based groups

• Can be utilized together with several different group related services

Conference calls, Presence service, Messaging, etc.

Messagingserver

Delivery

list:

Paul

Lena

Lisa

I want to send a message to Paul,

Lena and Lisa. To optimise the

radio interface traffic I will utilise

messaging server to do the

distribution

Use IMS group

management to create

message delivery list

Paul

Lena

Lisa

Message

Message

Mes

sage

Message

Messagingserver

Delivery

list:

Paul

Lena

Lisa

I want to send a message to Paul,

Lena and Lisa. To optimise the

radio interface traffic I will utilise

messaging server to do the

distribution

Use IMS group

management to create

message delivery list

Paul

Lena

Lisa

Message

Message

Mes

sage

Message



Group Information • Group Identifier

• Group Specific Information

Group Information

Group Properties (visibility / duration)

• Service Specific Information

How the group be used in the context of a specific service

Access list in the context of presence service

Delivery list in the context of messaging service



Capabilities to manage groups • Create(delete) a group

• Add(remove) members to(from) a group

• Get member list of a group

• Get group member identification(or properties)

• Modify group member properties

• Get group(or service) specific information

• Modify group(or service) specific information

• Simultaneous access from multiple terminals

• Search

Notification • In the event of group information change



Charging • Pay per transaction

• Volume based charging

Volume of transferred group content

• Indirect charging

When it is incorporated as part of a service


Push-To-Talk 개요 (1)

PTT는 다음 서비스와 유사함

• TRS

그룹 통신 지원

특정 순간에 한 사람만 발언할 수 있음

버튼을 눌러서 발언권 획득 후 발언

신속성, 즉시성이 강조되는 통신 방법

기지국을 통한 릴레이 기능으로 지리적 제한이 없음

• Instant Messenger (IM)

친구 및 조직도 관리

Buddy의 프레즌스 정보 공유

즉시 통신, 그룹 통신



TRS, IM에 비해 PTT의 장점 • TRS는 비표준의 기지국을 전용망으로 구축해야 하므로 구축 비용이 높은 데

반해, VoIP 기반의 PTT는 CDMA1x, EV-DO, WLAN 등 유무선 IP 인프라를 활용하므로 구축 비용이 낮음

• TRS는 비표준의 전용단말기를 사용해야 하므로 단말기 가격이 비싸고, 크고,

디자인이 투박하며 단말기 선택의 폭이 작은데 반해, PTT는 휴대폰, PDA, PC

등 다양한 IP 단말기에 응용 형태로 구현할 수 있으므로 전용단말기 구매 필요성이 없음

• TRS는 기지국 수가 작아서 지하, 도심 외 지역에서는 통화가 되지 않으므로

TRS 단말기 외에 휴대폰을 별도로 소지해야 하는데 반해 PTT는 이미 구축된

IP 인프라를 활용하므로 음영지역이 아주 작음

• TRS는 그룹 구성원 설정이 제한적이며 프레즌스 정보 확인이 불가한데 반해,

PTT는 인스턴트 메신저처럼 프레즌스 정보를 가시적으로 보일 수 있음

• 인스턴트 메신저를 휴대단말기에 적용할 경우, 문자 입력이 불편한 데 반해

PTT는 텍스트 외에 음성을 이용할 수 있으므로 무선 메신저 서비스에 적합

• Video 등 멀티미디어 통합이 용이함



Presence-based PTT (Push-to-Talk) 서비스 시스템

• All-IP 기반의 유, 무선 인터넷 환경에서 음성 및 텍스트 기반의 일대일 및 그룹

즉시 통신(instant communication) 서비스를 제공하기 위한 시스템

주요 기능

• Buddy list 및 그룹 관리

• 프레즌스 관리

• 1:1 및 1:N instant voice communication

• 1:1 및 1:N instant text communication(IM)

표준

• Call control protocol : SIP

• Media stream protocol : RTP, RTCP

• Presence management protocol : SIMPLE

• System management and provisioning : SNMP



기능 및 도입 효과

• 1:1 및 그룹 (1:n)간 동시통화 조직 내 신속한 의사전달 및 의사결정

• 조직 구성원간 프레즌스 정보 공유 협업을 통한 효율성 제고

주요 활용 사례

• 운송/창고/제조업체의 현장-사무실간 통신

• 유통 (할인점 등) 현장에서의 통신

• 빌딩 내 팀원간 즉시 통신

• 영업, 현장 A/S 등 신속한 업무 처리

• 병원 등 의료기관 내에서의 신속한 통보/조치

• 놀이공원/위락시설 등에서의 구내무선통신

• 게임

• 텔리매틱스


PTT 업계 동향 (1)

Nextel Communications

• 서비스 명 : “Direct Connect”

• 2001년 당시 7.2 M subscribers

• 일인당 평균 월 사용요금 : $72(타 이통사 평균 : $45)

• 가장 낮은 서비스 이탈율(2.1%)

• 현재 Motorola iDEN(integrated dispatch enhanced network) 방식

• VoIP 기반 PTT 방식 추진

Qualcomm 과 미국 내 독점 계약

Verizon Wireless, Sprint PCS, AT&T Wireless

• 2003년 중 PTT 서비스 개시 선언

• VoIP 기술 기반

Ericsson, Nokia, Siemens

• PTT 표준화 공동 추진


PTT 업계 동향 (2)

Ericsson

• “InstantTalk”

• PTT demonstration at CTIA Wireless 2003

• Over CDMA2000 and GSM/GPRS

• IMS-based

가입자수 예측(Strategis Group, ADL)

• 17M subscribers by 2004 in America

• From 3M today to 9.5M by 2005 in Europe


기술 표준

SIP

• RFC3261(SIP : Session Initiation Protocol)

• Call and session control

SIMPLE

• RFC3265 (SIP - Specific Event Notification)

• Presence management

• Instant messaging

RTP

• RFC1889(A transport protocol for real time applications)

• Real time data transport

• Voice and video


주요 기술

그룹 세션 관리

• 유연한 그룹 정의 및 관리

사전 정의 그룹

Ad-hoc 그룹 정의

멤버 추가 및 삭제

• 그룹 세션 설정 및 해지

발언권 제어

• 다양한 발언 우선 순위 제어

RTP 미디어 릴레이

• RTP 패킷 릴레이 및 멀티캐스트

• RTP over UDP/TCP


PTT 서비스 구조

SIP Proxy Server

(or KT Softswitch)

PTT Client (PC)

PTT Application

Server

SIP

PTT Client

(Cellular Phone)

PTT Relay

Server

SIP

RTP Stream

Presence

Server

SIP signaling

RTP Stream

Public Wireless Network

(CDMA1X, EV-DO)

Hotspot area

(WLAN Network)

OAM Server


PTT GUI Sample (1)

User Interface - Presence

Push to talk start button

Multiple choice box

to select participants

Buddy list view

우리팀 (3/4)

팀장 (전화중)

팀원1 (오프라인)

팀원2

팀원3

기타

회사 (57)

CEO (1)

마케팅본부 (20)

마케팅본부장

마케팅1 (오프라인)

마케팅전략팀 (5)

마케팅2 (오프라인)

내상태 - 온라인


PTT GUI Sample (2)

User Interface – PTT Group Session

Text Instant Messaging Window

Session participant view

팀장

팀원2

팀원3

Session1 - 대기중


Thank You !!!

E-mail : [email protected]