Monthly Archives: October 2013

RCS ( Rich Communication Suite )

What is this fuss about RCS ? For the past few weeks I’ve been trying to find the answer to this one .

After much information gathering i made myself understand that  :-

The Rich Communication Services programme is a global initiative to deploy inter-operator services within an industry ecosystem.

Marketed by the GSMA under the brand name joyn,  RCS is an upgrade that marks the transition of messaging and voice capabilities from Circuit Switched technology to an all-IP world.

Wider and large scale IMS deployment, interoperability between different terminal vendor RCS clients and RCS service interworking between operators are the key aims of the RCS Initiative.

Whats special about RCS ?

  • Enhanced Phonebook: service capabilities and enhanced contacts information such as presence and service discovery.
  • Enhanced Messaging: enables a large variety of messaging options including chat, emoticons, location share and file sharing.
  • Enriched Calls: enables multimedia content sharing during a voice call, video call and video sharing (see what I see).

RCS releases

Five releases of the RCS specifications have been made to date. Each release expanded the scope of its predecessor.

lRelease 1 : Offered the first definitions for the enrichment of voice and chat with content sharing, driven from an RCS enhanced address book.
lRelease 2 : Added broadband access to RCS features: enhancing the messaging and enabling sharing of files.
lRelease 3: Focused on the broadband device as a primary device.
lRelease 4: Included support for LTE.
lRelease 5: The most recent release, global interoperability is a key aspect of these specifications.
……………………………………………………………………………..

As the team developed a web client for making and receiving SIP calls over websockets through a proxy SIP server , I felt its an  achievement big enough. To integrate it with RCS ( Rich Communication Suite ) stack appeared as a very complicated job .

I began by adding RCS specific standards modules one by one instead of importing the whole stack / library all together  .

So the modules for XCAP for buddylist  , MSRP for file transfer , geolocation  mapping , cloud sync of phonebook and message book have begun taking shape . In essence following features set are expected out of a RCS enabled Client  ( short outline )

Provisioning

  • · OAUTH integration with operator customer portal
  • · RCS HTTP Auto-Configuration 
  • · Manual IMS credentials, typically reserved for testing / troubleshooting RCS Services

RCS services:

  • · Service Discovery
    • OPTIONS and Presence supported
    • Address book polling
  • · 1-1 Chat
    • IMDN
    • Is-Composing
    • Store & forward / deferred message and notification delivery
    • Hotfixes compliant
  • · Group Chat
    • Hotfixes compliant
    • Is-Composing
    • IMDN
    • Geo-location Push
  • · File Transfer
    • MSRP based
    • HTTP based
    • Store & forward
    • Geo-location push via FT
    • vCard sharing
    • Thumbnail support
  • · Voice & video
    • Best effort voice
    • Transcode 
  • · Network Address Book Support
    • Synchronization to SyncML based network address book
    • Contact import from Google, Facebook etc.

…………………………………………………………………………………………………..

At this stage i will also put in a bit more about RCS e

RCS e

What is the difference between RCS-e and RCS?

RCS-enhanced (RCS-e) is the currently available version of RCS, developed to speed time to market. It offers enhanced features such as instant messaging, live video sharing, and file transfer across any device on any network operator.

RCS e Benefits :

Focus on advanced communication
– chat , file transfer , video sharing
Easy to Use
-zero touch from end user perspective
-minimal setup for subscribers
-Interoperability across devices , infrastructure components and service providers
Low barrier to entry / simplify networks
– Capability discovery using SIP OPTIONS
– Less impact on network elements and handset battery
– Lack of presence server reduces cost and time to market
Universal
– Allows implementation in lower range devices
– One common device specification

RCS-e Customer Value Proposition

 New IP Communication Services , Profile Sharing , Native Device Integration
rcs5 rcs6

RCS e Characteristics

Dynamic Capability Discovery
User Perspective
network detects when user attaches with RCs e device
detection triggers network provisioning and client configuration
authentication by network
SSO / GIBA in 3G coverage
SIP Digest in Wifi
Encryption for Wifi access
TLS for SIP and TCP media or IPsec
SRTP for UDP or IPsec
NAT traversal and Keep-alives
…………………………………………………………………………………………..

WebRTC SIP / IMS solution

We started in winters on 2012 with Webrtc . At time time it just looked like a new car design that might fade away when new ones comes .

What really is WebRTC ? I made an entry on it  here .

Around nov – dec 2012 , team and I spend the time learning the nitty grities of HTML5 based media operation and Javascript sip stack of SIPML. I remeber toward the end of the year ie before Christmas , We were done with the explanation and education aspects of WebRTC , a technology that will revolutionize communication in ages to come , at-least so says the numerous other blogs ,  and documents i read so far .


The flow between

client BOB -> webrtc2sip Gateway -> SIP server -> client Alice

can be  understood with the callflow of a simple SIP Invite initiated from one html page towards another which passes through the configuration of gateway to IMS world ,  SIP Telecom Application server , Database , nodes of IMS environment etc.

For the purpose of a simple Explanation a simplified call flow ca be depicted as ,

webrtccallflow

A very high level architecture of solution deployment in IMS world could be

solution arch2

As the solution matures into a full fleshed project . The alpha version has been released with the following feature set . The WebRTC platform Suite offers a easily deploy-able solution to enable communication

Alpha Release WebRTC platform Suite

  • Single Sign On
    •  Login with id and password to access all services
  • Audio / Video Call
    •      Call Hold / Call Transfer
  • Messaging:
    •      SIP Instant Messaging
    •      Message to Facebook Messenger
    •      Message delivered as Email
  • Chatroom :
    • group chat between multiple users . Room is created for set of users .
  • Video Conferencing :
    • video chat between multiple parties . Room is created for set of users .
  • File Transfer :
    • Sharing of files from local to remote , in peer-to-peer and broadcasting fashion .
  • Third party Webservices :
    • Widgets like calendar , weather , stocks , twitter are embedded.
  • Visual Voice Mail :
    • Record and deliver voice message to recipients voice mail inbox which can be accessed/ played from web client .
  • Phonebook :
    •      cloud integration
    •      add new entries
    •      add photos to contacts identity
    •      import contacts from google account
  • Click to Call :
    •      Drop down list of contacts form mail call console
    •      2 step Click to call from Phonebook
  •  Presence :
    •      Publish online / offline status
    •      Use Subscribe / notify requests of SIP
  • WS to SIP Gateway :
    • Conversion between the signal coming from the  WebRTC  and SIP client  to the  IMS core
    • Conversion of  “voice/video ” media  between sRTP and RTP
    • Conversion of other media (data channel) towards MSRP and Transcoding.
  • Support of ICE procedure .
    • Implementation of a STUN server. 
    • QoS Support  

Beta Release WEBRTC PLATFORM SUITE

  • Logs :
    •      calls logs
    •      Message logs
  • User Profile :
    •      user details like address , email and social networking accounts
    •      Phonenumber for GSM integration through SMS
    •      User’s Media storage like Pictures , profile picture , Audio , video
    •      File sharing documents storage for future access in the same format
  • Real Time and Offline Analytics
    • service usage with graphical and tabular history  trends
  • Session Management :
    •       Single Sign-on
    •       Forgot password regeneration using secure question
    •       Registration of new user account
    •       Logout and clearance of session parameters
  • Security :
    •      No redirection to any page through url entry without valid session
    •      No going back to home page after logout by back button on browser
    •      No data vulnerability
    •      Multiple login through different devices handled
  • OAuth :
    •      Login via IMAP / token through facebook and Google
  • Phonebook with Presence functionality inbuild .
  • Directory Service based on country / region
  • Geolocation of approximate location detection of device logged in and visibility to  others

webrtc solution

WebRTC client deployment view , accessible devices , network elements

WebRTC deploymenet overview and inetraction with other network elemets such as gateway , cloud storage ,  sipserver , IMS

WebRTC deploymenet overview and inetraction with other network elemets such as gateway , cloud storage , sipserver , IMS