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13
Bringing it all Together –
the New Network
Architecture
13.1 INTRODUCTION
In Part 2 of the book we have explored some of the key existing services
and how they may progress. In this chapter I would like to take you a little
way into the future, for a view of what the network may look like and
explore how a service or group of services may fit together to form a
useful example of where next-generation networks will take us.
Let us go over the components of the next-generation network:
†
Media gateway and signalling gateways, these are the interfaces back
to the Time Division Multiplex (TDM) world of the current Public
Switched Telephone Network (PSTN) and Public Land Mobile
Network (PLMN).
†
Media gateway controllers (call servers), softswitches and application
servers. These are where the new services execute.
†
Media servers (or Internet Protocol Interactive Voice Response (IP-
IVR)), these are the components that provide the voice of the network
and automate a number of voice enabled applications.
†
Directories, these will store all the configuration information about
services, users and equipment inventory, for example:
†
Application-specific configurations for each client/customer.
†
Personalisation information on a per user basis (buddy lists, prefer-
ences, usage statistics, favourites and bookmarks).

†
Device information and capabilities.
Next Generation Network Services
Neill Wilkinson
Copyright q 2002 John Wiley & Sons, Ltd
ISBNs: 0-471-48667-1 (Hardback); 0-470-84603-8 (Electronic)
†
Location of application components and whole service instances.
†
Service translations (freephone style service translation info).
†
Security tokens (access control lists and encryption keys).
†
User location information.
†
Virtual Home Environments (VHEs).
†
Service tags, flags to indicate what the user is allowed to do. For
example if someone hasn’t paid their subscription fee, then a flag
could be present to prevent them from using any billable services.
†
User scripts (for example written in Call Processing Language –
CPL).
†
Application scripts (VoiceXML scripts say).
†
Agent skill sets for call centre applications, the profile of an agent’s
capabilities could be held.
†
Call routing rules.

†
Billing information and usage records.
†
The directory will hold the information in Extensible Markup
Language (XML), because XML brings with it the power to represent
the data in a structured way that allows the display and transforma-
tion of that data to and from any device.
†
Packet network, the infrastructure that supports all the components
above. It will be using protocols such as Multi Protocol Label Switch-
ing (MPLS) to both segregate traffic flows and to manage quality of
service aspects.
†
Transport infrastructure, this will be fibre optic cables providing high
amounts of bandwidth managed via Dense Wave Division Multiplex-
ing (DWDM) and broadband copper for low cost Small to Medium
Enterprise (SME) and residential access. For mobile devices the access
will be via Universal Mobile Telecommunications Service (UMTS)
data and voice services.
Now that we have the components how do they fit together? They say a
picture speaks a thousands words, so I’ll use a picture to give some idea of
the architecture.
13.2 THE NEXT-GENERATION NETWORK
ARCHITECTURE
In the introduction to this chapter we highlighted the components that
will make up the next-generation network architecture. Figure 13.1 shows
a view of the components and their relationship to each other to form the
physical architecture of the network.
The technologies such as DWDM and MPLS will form the basic infra-
structure (glue) that will interconnect all the nodes. MPLS will be used to

segregate the different type of data that will be transported on the infra-
BRINGING IT ALL TOGETHER – THE NEW NETWORK ARCHITECTURE168
structure. The data will be one of two types: media streams (voice, video
and other forms of content) and control data (signalling).
The bottom-most layer will be the media transport layer, in the case of a
next-generation network to replace the circuit switched network of tele-
coms operator, this layer will carry lots of telephone calls. This is shown in
Figure 13.1 as the voice transport layer. Part of this layer’s function will be
to groom incoming traffic from the broadband local loop, for example
from cable and digital subscriber lines. The media traffic from these custo-
mers will be delivered over the media layer and their signalling messages
from the intelligent access devices, passed to the signalling layer.
Above the media transport layer will be the signalling layer, carrying all
the control messages to and from media gateways and their media gate-
way controllers, encapsulated Signalling System number 7 (SS#7) signal-
ling messages carried from signalling gateways to media gateway
controllers and softswitches and session initiation protocol (SIP) messages
between SIP clients and proxy, redirect and SIP application servers.
The very top layer will be where all the servers reside to allow fast
communication between distributed applications and between different
service platforms. This layer will also carry all the information to the
operational support systems and business support systems for mainte-
nance and billing. This layer will also contain all the directories and
databases that will store all the location and configuration information
about customers/users and the services. This layer could also hold the
13.2 THE NEXT-GENERATION NETWORK ARCHITECTURE
Figure 13.1 The next-generation network architecture
169
Service Control Point (SCP) of a conventional circuit switched Intelligent
Network (IN). The SCP in this case would have implemented an Internet

Protocol (IP) interface and would no doubt be communicating (via stream
control transmission protocol) with a media gateway controller or soft-
switch masquerading as a service switch point. This would provide old
and next-generation network service integration.
The final and probably the most important parts of the network will be
the firewalls and routers that interconnect the networks of different
network operators and service providers. In Figure 13.1 these are
shown as firewalls and the interconnect packet filter router.
13.3 A SERVICE EXAMPLE
Imagine a couple of young professionals in a few years’ time going about
their hectic lives, both have Personal Digital Assistants (PDAs) with voice
(UMTS and Digital European Cordless Telephony (DECT)) and video
capabilities, plus close proximity Bluetooth capabilities. The service
provider they got their PDAs from provided them with basic packages
containing a bundle of the following services: location-based advertising
from a selection of reputable high street names, real-time stock, traffic and
news feeds, access to an online diary/agenda and presence service, with a
bundle from their UMTS and fixed line providers that allows them to use
their PDAs as fixed line handsets in their homes, because they get free
local calls in the evenings from the fixed line provider and of course the
now ubiquitous Unified Communications (UC) package.
Peter and Jane are both in work, but it’s getting close to the end of the
day and Peter feels like he’s had a tough day and would like to eat out and
see a movie. He checks Jane’s online diary/agenda to see if she has any
late meetings (Jane has previously allowed Peter read access to her diary/
agenda). She doesn’t, so Peter looks up on the web what the local cinema
is showing. There is a couple of showings at the 9:30 p.m. slot for the latest
summer blockbuster, which he thinks Jane might just be persuaded to
watch. So he puts a one hour reservation on two tickets, which he will
need to confirm.

He’s not sure what food he would like, so he decides to have a stroll into
town to have a look around the restaurants to see what takes his eye. On
leaving his office building the network detects that he has left his office
cell, and this triggers a script that diverts all calls to his office number
directly to his UC service. The service script is smart enough (its in the
network, so can interrogate the source of contacts) to distinguish work
calls from personal calls. Peter has set up an additional list that allows
calls he has nominated as personal calls that arrive at his office number, to
be routed to his PDA and not the UC platform.
Passing the Italian restaurant his PDA flashes up the specials for the
BRINGING IT ALL TOGETHER – THE NEW NETWORK ARCHITECTURE170
day, this catches his attention and he really ought to find out if Jane would
like Italian and the movie. He goes to his presence service where he has
Jane in his buddy list. He sees that Jane is still at work and set to be
reached by text messages only. Peter decides Jane must have someone
with her who caught her at her desk before she set off for home.
Peter sends Jane an instant text message with the film details and the
Italian restaurant menu, plus a little note explaining his idea. Jane has got
someone with her and simply replies OK to Peter’s message. Peter
quickly confirms the tickets for the movie and pays for them with his e-
wallet that is linked to his PDA device identity (this creates a record that a
transaction took place from Peter’s PDA, the access to the services them-
selves are charged, but a small fee is levied from the transaction by Peter’s
service provider).
Jane finishes her impromptu meeting and quickly looks to her presence
service to see if she can tell where Peter is from her buddy list. She can see
that Peter is in the middle of town. She quickly calls him as she is leaving
the office simply by selecting the icon of Peter in her buddy list. They
quickly arrange to meet in a bar where they can decide on dinner. Jane is
having second thoughts about the Italian. Having browsed a few more

menus together from the bar, they decide on a local Chinese restaurant.
After the meal and movie, they leave the cinema to find their train has
been cancelled, no driver again, this was sent to both their PDAs as part of
the travel updates service they subscribe to, better find a cab.
When the couple arrive home, both Jane’s and Peter’s handset swap to
DECT for voice and Bluetooth for their home network. Peter and Jane’s
PDAs now share a common number and are both just handsets of the
same DECT base station. When someone calls the house number, both
PDAs will be paged. However, since the PDAs are intelligent devices and
can receive caller information over the DECT interface they can apply a
local profile that can decide whether to ring (playing a distinctive tune for
different callers) or not.
Peter and Jane both retire for the evening leaving their PDAs in their
cradles.
This simple story highlights some of the capabilities of a combined
services next-generation network. All of the service features described
will be possible in the next 10 years or less, in fact some are appearing
at the time of writing!
13.3 A SERVICE EXAMPLE 171