The IP Multimedia Subsystem (IMS) represents the new
IP-based telecom network that will enable a whole host of exciting telecom
services such as multimedia conferencing and video on demand. It promises to
revolutionize the telecommunications industry by replacing the long-cherished,
circuit-based traditional call model with interactive, multimedia-enabled,
Internet Protocol (IP) based sessions that can incorporate any device, on any
access network, from anywhere, at any time. IMS allows the convergence of data,
voice and mobile network technology over an IP-based infrastructure.
Employees can use multi-mode wireless handsets on an
enterprise Wi-Fi network while at the office, and have their conversations
continue onto the cellular network as they leave the premises. Conversations can
take on a new dimension as a video conference call could include one participant
using a camera-enabled desktop PC and another participant using a camera-enabled
mobile handset. The nature of calls can adapt while in progress, allowing
additional participants to join, and allowing current participants to change
their mode of operation.
Arriving at the company office, a participant can
transition from a mobile phone to a desktop system as one continuous session,
without dropping the call.
Based on Today's Internet Technologies
Subscribers to IMS-based networks interact with a common core network
through dynamic sessions rather than through a traditional call model. These
sessions provide access to all of the telephony services available today, as
well as supporting a new class of IP-based services available over the Internet.
In traditional telephony, the call model permeates all aspects of the network,
including subscriber devices, circuit infrastructure, call processing, and even
the definition of the databases containing subscriber profiles. For example, the
Home Location Register (HLR) is defined to support the mobile telephony call
model, and is designed to be accessed using wireless-specific protocols such as
GSM MAP or ANSI IS-41. As IMS sessions replace calls, and IP-based protocols
replace traditional synchronous protocols, IP-friendly will be replaced by HLRs,
which are all-inclusive customer repositories. Because the transition to IMS
will be evolutionary, the functions provided by today's HLRs will remain in IP
networks-but the directories used to support them will be based on
technologies used in today's Internet, not based on extensions of
yesterday's HLRs.
One of the core components of the IMS architecture is the
Home Subscriber Server (HSS) that identifies a carrier's subscribers, the
characteristics of each customer's connected devices, the services to be
provided, and the customer's preferences for those services. The HSS is a
media, network, and device-agnostic functional evolution of the Home Location
Register.
An Opportunity for Communication Carriers
IMS and its HSS requirement potentially adds yet another repository to the
long list of databases that wireless and wireline carriers must synchronize and
maintain. Today's communication carriers struggle to maintain consistent,
up-to-date databases for customer billing, service provisioning, customer
relationship management, and session management. Deploying an HSS can add to the
crippling level of cost and complexity with which communication carriers must
grapple.
Complementing IMS with Identity Enabled Services
IMS offers an exciting opportunity for communication carriers to reach into
markets where they currently lack a strong presence. For example extending
services to customers over networks beyond their direct control. The strategy is
simple: establish a common user repository that can support IMS services, and
integrate identity management with the solution in order to more effectively
provide services to their customers both directly and indirectly and through
affiliates that are part of a federated circle of trust.
The IMS promises to unify the wide and disparate networks
on which subscribers and their devices might reside, from public access Wi-Fi
networks to the public-switched telephone network. In order to accomplish this
feat, carriers must establish the core IMS network that includes a repository
for users, devices, and their preferences.
At this point in their evolution, carriers have a choice:
create yet another independent user repository that requires provisioning and
synchronization with existing ones, or take the opportunity to base HSS services
on a common user repository that consolidates a carrier 's multiple
repositories into one.
 IMS offers
an exciting opportunity for communication carriers to reach into markets
where they currently lack a strong presence. |
Using a proven, common user repository based on open
standards is a move towards the IP-based future that IMS itself promotes. This
approach gives carriers the opportunity to reduce cost and complexity and at the
same time that they prepare to move into the future with increasingly
sophisticated services. With one repository to support using one set of
carrier-grade server, software, and storage products, carriers can better focus
their limited staff and capital budgets and reduce the expense of supporting as
many repositories as they have services to offer. Whereas IMS supports
communication sessions across multiple networks and devices, it does not address
the authorization, access control, and user management for IP-based services
that carriers already use to attract new customers and reduce churn. Mobile
music, ring-tone downloads, on-line gaming, and camera phone photo processing
are examples of IP-based services that are outside of the IMS purview but which
are just as important to carriers from a revenue standpoint.
Once carriers develop a solid identity-management
foundation, they can begin to envision compelling services that would be
impossible without such technologies in place:
-
Integrating identity management, digital-rights
management, and content-delivery services could allow subscribers to listen to
their music on their MP3-enabled mobile handsets, higher-quality audio on their
desktop PCs, and CD-quality audio through their set-top boxes. Knowing the
subscriber, their devices, and their capabilities allows the three technologies
to work in concert to deliver a compelling new service.
-
Extend these capabilities into the video realm, and imagine a subscriber
purchasing a pay-per-view movie and beginning to watch it through a set-top box.
The subscriber pauses the movie and is able to continue watching it on different
devices while embarking on a business trip: on a mobile handset while waiting
for a flight, and on a laptop on board a Wi-Fi enabled aircraft en route.
-
A network-hosted, personal address book could support subscribers when making
calls on mobile devices, sending e-mail from a desktop PC, and when addressing
an envelope from data on a wireless PDA.
-
An identity-management foundation can leverage a range of strong
user-authentication mechanisms that are more secure than simple possession of a
subscriber 's handset.
Demand for Even More Repositories
Given the number of new services that communication carriers foresee
deploying, this pattern is likely to repeat unless they change strategies. For
example, 3G wireless networks require enhanced HLR services with integrated
RADIUS authentication. Public access Wi-Fi networking is usually based on RADIUS
authentication with specific modifications to support users roaming from other
carriers' networks. The IP multimedia subsystem needs a Home Subscriber
Server, which can be supported with the DIAMETER authentication protocol. VoIP
services require a Session Initiation Protocol (SIP) server along with
authentication services and repositories to manage session state.
One way to move into the future while containing the cost
and complexity of deploying new services is to transition to a common user
repository that uses a single directory to store user information for all
applications, and which is based on the same Internet technologies that IMS
embraces. There is no better opportunity for carriers than to deploy such a
repository as they deploy IMS services.
Thus, IMS represents a new paradigm through which
operators/ carriers can increase ARPU and monetize their telecom infrastructure
whether that's wireline or wireless. And also, generate revenues on new
services such as “see-what-I-see” video sharing and multiparty gaming. The
ability to do these things 'on the fly' opens up a number of new and
innovative user-to-user and multi-user services that operators are eager to
rollout - and make money!
Kapil Sood
director-Telecom Sun Microsystems India
vadmail@cybermedia.co.in
Page(s) 1
Print
Comment
Email
Digg
Del.icio.us
Reddit
