The Next -Generation Service Infrastructure on an IP Platform

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Oct 26, 2013 (3 years and 9 months ago)

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The Next
-
Generation Service Infrastructure
on an IP Platform

Dr. Wolfgang Essig, Siemens AG, Germany, Batic IT Review 2 '99

In his article the author will elaborate upon the driving forces of convergence. He will look at
impacts on markets and technologie
s. The 21st Century Network is, in its earliest phase, a
network of co
-
existence for most incumbent carriers. It is a simple matter of the bottom line.
Business cases will be mandatory.

Introduction

Siemens is fully aware of the role of open I
nternet
-
based networking and applications
technologies. Re
-
organization over the last few years has merged our extensive IT operations
with our telecommunication activities in carrier and enterprise networks.

Following this direction, Siemens has announced

another restructuring and focusing activity
-

the
establishment of a new US
-
based entity, Unisphere Solutions Inc. Built around E
-
commerce and
Internet
-
centric applications and networking technologies, this company will provide solutions
that parallel the

expectations of all advanced telecommunications operators. The goal is nothing
less than to provide a next
-
generation service infrastructure. While this operation is going to
follow a start
-
up mentality, agility and focus on customer's needs
-

it draws on

the vast resources,
support, experience and presence of the global Siemens company.

It is important to note that this company has been designed with an emphasis on next
-
generation
networking solutions, and it therefore will provide extensive product and i
ntegration capabilities
with respect to application layer services. These capabilities will be drawn from the availability
of today's open, Internet
-
based technologies
-

driving the ongoing standardization efforts in the
industry.

Incumbent operators alrea
dy provide a service network and platform for a complete set of today's
telecommunications services. The migration of these service platforms into the future
-

and their
transition onto the next
-
generation service infrastructure
--

is the long
-
term goal.

W
ith just that in mind, we are set to provide a networking solution that is built upon the principle
of ubiquitous switching capability, packet division multiplexing. This allows the consolidation of
existing network technologies onto one service platform a
s a first step, by fully supporting IP,
ATM, FR and MPLS switching in native mode throughout the entire core and edge infrastructure
at unprecedented line speeds. Tightly integrated with our SDH and DWDM transport
infrastructure, this will then provide the

basis for the future transition of today's services and
customers onto the next
-
generation service platform.

Core and Edge Switching Platforms
-

Trunking and Access

Two new products offered by Siemens will provide IP connectivity from access
up to the highest
core interface speeds. The strategy behind these two products is to provide highly functional,
integrated and flexible access switching (IP, MPLS, FR, ATM) in the network access and edge
positions and extremely large
-
scale core switching
(IP, MPLS, ATM) in network edge and core
positions. The solution employs packet division multiplexing technology
-

which translates into
ubiquitous switching capabilities for any existing technology in native mode.


Integration of these products under one network middleware and network application solution
will furnish operators with any granularity of VPN, CoS, SLA and bandwidth wholesaling
capability.

However, while the final destination of a converge
d services network is the goal
-

it is the
journey that must pay the way. Providing seamless integration as a basis for near
-
term service
convergence is the unique value proposition that Siemens established as its most critical goal for
network solutions.

This solution allows immediate consolidation of all data service networks (and even transport
networks) onto one service network. From there on it is a network management task to provide
customers with the transition from, e.g., IP based services and ATM
-
b
ased services to one
comprehensive MPLS
-
based service bundle. Tight integration with an SDH or SONET
-
based
infrastructure will provide complete independence, flexibility and pure SW control of interface
speeds, service type (IP, ATM, FR, MPLS, PPP) and swi
tching type (IP, ATM, MPLS).


The two products providing this next
-
generation Internet service platform are the Core Switch
and the Edge Switch

• Core Switch (CS):
This is a family of native IP and ATM

switching products. The capacity for
IP, MPLS and ATM forwarding can be dynamically allocated, e.g., for VPNs and wholesale
overlays. The internal mechanisms allow traffic engineering across layers 2 and 3. Each CS port
(physical or logical) is individual
ly configurable for ATM, MPLS or IP switching, with support
for terminated FR and ATM virtual circuits and a wide variety of IP encapsulations.

Integrating seamlessly with SDH/SONET and DWDM infrastructures, this product can achieve a
tremendous fan
-
out t
hrough the aggregate support of a maximum of 64 OC
-
48 in its first release.
Connected to an SDH/SONET infrastructure, this translates to a tributary fan
-
out of more than
3,000 E3/T3
-

each individually SW
-
configurable to be FR, ATM, MPLS or IP switching an
d,
moreover, up to 100,000 FR/ATM VCs per STM
-
16/OC
-
48 can either be SW configured to be
terminated and switched locally, or switched right through. Thus, no HW exchange or
modification is necessary for changes in transmission speed, traffic type or even e
quipment
change of the connecting device
-

a breakthrough in operational efficiency.


Needless to say, the CS employs the most rigid reliability and failover precautions, right down to
individual SW co
mponent updates. Lower layer switchovers (e.g., APS) are hitless for higher
layers, switching matrix redundancy is without loss of packets, cells or timing.

The CS fulfills the most scalable peering and processing requirements both for IP routing (BGP,
OSP
F, IS
-
IS) as for P
-
NNI ATM routing.

• Edge Switch (ES):

This is a new generation of edge device, purpose
-
built to address service
provider challenges at the edge of the IP network. With its unprecedented density, wire
-
speed
performance, carrier
-
class relia
bility, multiple service classes (the foundation for VPN and
premium service deployment) and sophisticated Quality of Service (QoS) capabilities, the ES is
the ideal platform for service providers who need to meet large
-
scale demands for IP access
connecti
ons
-

with especially strong focus on VPN and wholesaling applications. All major VPN
technologies are supported for hundreds of VPNs per interface port
-

including static and
dynamic virtual routing machines.

The edge switch is geared for termination of h
ighly aggregated ATM or FR
-
based access to the
Internet via DSLAMs or MSAPs, as well as highly integrated TDM interfaces supporting
hundreds of (F)T1 links per interface port. The maximum configuration data applies to a single
shelf
-

demonstrating the eno
rmous advantages with respect to required co
-
location space and
power consumption, when compared with today's access and edge routers.

The ES provides an advanced traffic engineering tool with support for Multiprotocol Label
Switching (MPLS).

It employs th
e same rigid reliability and failover precautions as the CS, down right to individual
SW component updates. Lower failure switchovers (e.g. APS) are hitless for higher layers.

The ES fulfills the most scalable peering and processing requirements for IP rou
ting (BGP,
OSPF, IS
-
IS)
-

as necessary to support hundreds of VPNs, as well as wholesale to many retail
service providers.

Access Network Functionality

The access network splits up into a variety of access concentration, aggregation and switchin
g
network elements. We would like to split the access network into essentially three network
categories:

• Multiple Service Access Platforms (MSAP)

• TDM
-
based Access Platforms (DACS, PDH, ...)

• Customer
-
located Integrated Access Devices (IAD)

TDM
-
based
Access Platforms:

Siemens provides a number of product families in the PDH, TDM MUX and Fiber
-
based
infrastructure equipment segments which are all available now.

However, through the Mediator (see below) Siemens offers integrated voice/data service
bundl
ing capabilities, which are geared for deployment in the new converged services
marketplace. The Mediator products have the distinguishing capabilities to integrate with
standard data equipment network and service management systems via SNMP, MGCP and INAP

interfaces, as well as providing mediation in respect to network maintenance, operations and
billing procedures.

Multi Service Access Platform (MSAP): Consolidates many of the individual functions found in
DSLAMs, ATM concentrators, internetworking and ga
teway equipment. First, it concentrates a
large number of relatively low
-
speed physical lines into a small number of high
-
speed physical
or virtual circuits. Second, an MSAP provides internetworking, switching and gateway functions,
converting traffic to t
he appropriate format for the upstream network, e.g., converting ATM
-
based voice traffic to PSTN or IP; or converting ATM
-
based IP data traffic to FR, Ethernet or
L2TP. Many flavors of MSAP functionality are provided in a variety of products, which are
ava
ilable now.

MSAPs are NEBS Level 3
-
compliant platforms that can be installed by a service provider in
campus, multi
-
tenant, or central office co
-
located environments, aggregating multiple IADs (see
below) or NTs to upstream networks
-

or, in the case of la
rge customer sites, directly connecting
to CPE equipment. Intelligent MSAPs will perform voice/data consolidation and mediation
functions
-

eventually under control of an MGCP
-
based service control. Initially MSAP
implementations will use PRI, GR303 and (l
ater) V5.2 implementations to interface with the
legacy voice access world. In all of these cases MSAPs will also aggregate the traffic up to
Mediators (MED) in order to provide voice bypass and service mediation solutions.

Integrated Access Devices (IAD)
are typically located at customer premises and perform the
task of integrating multiple traffic types over a single access line. Again, Siemens is introducing
new, service bundling capabilities especially geared for large
-
scale deployment of voice/data
int
egration services.

IADs serve the specific purpose of provider
-
based service management and monitoring in CLE
or campus network positions. Integrating service monitoring capabilities with the management of
SLAs and VPNs provides advanced integrated enterpr
ise VPN services
-

capable of bundling
voice/data communication over any service network.

Siemens will provide two generic solutions to bundled service delivery:

TDM
-
based service integration: Integration of services over DS0 equivalent TDM access allows
t
he immediate aggregation through Mediator devices
-

including intelligent voice mediation and
switching across any service network. This especially applies to n x DS0
-
based dedicated
Internet access services. The mediator can integrate and aggregate these
services either through
highly channelized T3/STM
-
1/OC
-
3 interfaces or through explicit E1/T1
-
based service,
including PRI and S2M.

ATM
-
based service integration: Multi
-
service integration of IADs across a variety of ATM
-
based access technologies will be a
ggregated, switched and mediated in the MSAP product
family. This provides the capability to integrate multiple services over an access infrastructure
-

with explicit VC
-
based fan
-
out of IP
-
based access services and, later on, also MPLS
-
based
access servic
es, including voice.

In general IADs offer a variety of value
-
added service bundling capabilities, including IP VPN
technologies, PBX services, LAN switching, etc. This product range is very multi
-
faceted.
Siemens has available a variety of next
-
generation

IP
-
enabled IADs, completing a CLE
-
based
service offering into medium to smaller locations of international companies. One key
functionality is the provisioning of immediate on
-
site local access provider selection.

Intelligent IADs will be able to be contr
olled via MGCP
-
based service deployment in later
releases.

PSTN/PSDN Mediation

Siemens provides a unique and very cost
-
efficient solution for the general topic of PSTN to
PSDN/Internet mediation. This service mediation solution addresses the p
roblems with today's
limited data
-
offload, service extension and VoIP transport mechanisms. It will be most suitable
to apply voice/data service mediation across an MPLS
-
based service infrastructure in the future
-

especially considering the native MPLS sw
itching capabilities of the Siemens core and edge
switching solution.

A highly flexible SW
-
based protocol mediation function
-

geared to provide service mediation
between the POTS/SS#7 PSTN world and any TDM or data service infrastructure
-

allows
flexible

service partitioning between various wholesale/retail customers for Internet Access,
native PSTN voice services, Internet
-
based voice transport and services, as well as intelligent
PBX networking over any transmission media
-

including IP, ATM and/or MPLS
-
based service
infrastructures. This solution is Bellcore compliant (Group D) and allows to peer with local LEC,
CLECs and other IXCs. Integrated INAP implementation allows to interwork with existing
value
-
added services.

The Siemens mediation SW product l
ine will also be available on a stand
-
alone carrier
-
class
server platform upon availability of open and interoperable standards. Over time this flexible SW
solution will evolve to provide STP/SS#7 connectivity and MGCP control services to other
parties and

intelligent Siemens access products
-

e.g., MSAP and IAD. Today Siemens is already
offering proprietary VoIP solutions based on the InterXpress product family, including
gatekeepers, gateways and service control applications.

In light of time
-
to
-
market co
nsiderations, this SW solution will first be integrated with the
flexible Mediator product line
-

still allowing control from future MGCP
-
based control
infrastructures
-

providing today's scalability, security and reliability issues with server
-
based
imple
mentations can be resolved successfully based on open standards.

This solution allows the concentration and location of new/existing NB
-
RAS, VoIP and CO
switches for retail customers in centralized network positions, where space constraints can be
avoided
-

thus providing a strong business case for centralized service hosting instead of
distributed high
-
maintenance co
-
location infrastructures. At the same time it frees this equipment
from SS#7 integration requirements, which are taken care of by the mediati
on infrastructure
service.

The mediator also supports class
-
4/5 equivalent network positions for out
-
of
-
region extensions,
as well as trunking applications. The integrated HW/SW solution fully supports the industry
-
leading scalability from 10
-

80,000 DS0
equivalent ports per node. Combined with extremely
high interface integration and low power consumption, this solution provides a very cost
-
effective alternate voice service platform
-

at a fraction of space and power required for
traditional PSTN equipmen
t.

In this network position the Mediator will connect to existing, as well as next
-
generation DLC
equipment (e.g., MSAP, DSLAM, DLC) through standardized PRI, GR303 or V5.2 interfaces.

In addition to PBX/PSTN to PSDN mediation, the Mediator Switch also sup
ports the transparent
transport aggregation of nxDS0
-
equivalent dedicated line data access over the same mediation
infrastructure
-

thus effectively serving as a DACS/PDH replacement today. With a capacity of
up to 2,500 T1s in a fully equipped (chT3) syst
em, this leaves ample room for integrated
voice/data access and bypass aggregation.

Conclusion

Siemens has gained vast experience in the design, manufacturing, delivery, installation, service
and maintenance of leading
-
edge networks internatio
nally. Our leadership in Voice, Data,
Transport, Mobile, Video, Multimedia applications and Terminal equipment is evident by our
market share in these areas. Our end
-
to
-
end portfolio of products, including applications, access,
edge, middleware and core, e
nables us to support operators in leveraging the different market
segments to achieve the required business objectives.

Siemens believes that support at a local level, where cultural and language knowledge play a
critical role in the interworking between
companies, is a key asset. This is demonstrated by the
fact that Siemens has built up a local representation, support and logistics infrastructure in 185
countries. Siemens offers truly global support to international operations with local response
times.
Furthermore, our global presence ensures uniform & guaranteed quality throughout all
regions.