Introduction to the Nortel Converged Office Solution.

1. Nortel Converged Office:
Solution Overview:
Although fairly new in concept…and in relative infancy in it’s adoption and
deployment in the Enterprise, there are nevertheless a number of solutions
currently available from a variety of vendors that offer the promise of true,
integrated Multimedia communication – the premise to Unified
Communications.
And the key word behind Unified Communications is of course integration.
It is this level of integration that differentiates one solution providers offering
from another. A fully integrated, presence enabled communication system
associates with hardware such as PC’s, telephones and mobility devices, and
applications such as IM and e-mail typically on the foundation of
communications platform that can handle, voice, video and data – something
that is becoming more available with IP telephony and converged networks.
What would this actually offer your business environment? Just imagine if the
once separate services and hardware requirements for phone, video
conferencing, voicemail, IM, fax e.t.c were suddenly integrated into one
service with minimum inconsistencies in hardware platforms.
Essentially the integration of disparate communications and media, desktop
applications, computers and mobility.
One part of a Unified Communications solution offering from Nortel is the
Nortel Converged Office: a solution brought about by the combination of the
Nortel Communication Server 1000E telephony system and the Microsoft
Office Communications Server 2007 platform. This effectively creates a SIP-
based VoIP solution which capitalises on Microsoft Office 2007 Desktop
Software accessing the business-grade telephony services and features
provided by the Nortel CS100E.
Where Microsoft OCS2007 typically provides the Applications for UC in an
organisation’s internal LAN/WAN environment, for users to have the ability to
make calls to and from the external PSTN, interoperation to a third-party
vendors SIP to PRI gateway is required. In this scenario however, the
telephony features the users have access to are limited to what the SIP
protocol allows for….usually a severely diminished featureset of an enterprise
class PBX.
The Nortel Converged Office solution has come about as a result of the
Innovative Communications Alliance between Nortel and Microsoft forged in
2007 to co-develop products and services in many aspects, including R&D. A
fully integrated, streamlined solution between these vendors systems has
emerged, as opposed to just interoperation by the OCS 2007 to other
manufacturer’s voice systems.

2. Users of the Nortel Converged Office have access to a powerful suite of
Nortel CS100E features which include:
• Nortel Unified Messaging (supported by Microsoft Exchange Server)
• Contact Center
• Interactive Voice Response
• Nortel Multemedia Conferencing
Microsoft OCS2007 allows users to have Instant Messaging, Tele-Presence
VoIP Telephony Presence at the desktop.
The Nortel Converged Office Solution integrates a number of elements to
provide a feature-rich multimedia environment:
1. The Nortel Communication Server 1000E – A highly reliable, VoIP
Enterprise PBX. It is comprised of some basic components:
• Call Server – Core Switching element of the CS1000E
• Signalling Server - The various tasks this component provides
is a Terminal Proxy Server for IP telephone sets, it provides SIP
signalling on behalf of the Call Server, it functions as “virtual
trunks” within the CS100E architecture and is also seen as
CS1000E Gateway providing access to TDM and PSTN
• Network Routing Service – The NRS can act as an H.323
Gatekeeper, and provide for either SIP Proxy Server (SPS)
function or a SIP Redirect Server (SRS) functions.
• Media Gateway – This predominantly transitions IP to TDM for
PSTN access. It supports analogue and digital telephones and
trunks and supports Secure Real-Time Protocol (SRTP) with
Media Gateway Controller Card (MGC) and Voice Gateway
Media Card (MC32S
2. Nortel Multimedia Converged Manager (MCM) – This is the key
component of the whole Nortel Converged Office solution, as it
provides communications between the CS100E and the OCS2007.
It is a Nortel application that runs on top of OCS2007 Proxy Server.
This MCM/Application Proxy Server will be a standalone computer in
either the Standard or Enterprise Edition Deployments
The MCM core functions are to perform translations between Directory
Numbers (DN’s) and User ID’s with Active Directory, provide
authentication for RCC as well as also being used for Numbering Plan
Normalisation.

3. 3. Nortel Multimedia Conferencing (NMC 5.0) – The NMC is a SIP based
application solution which provides Audio and Video Conferencing. It
augments the existing conference capabilities offered natively by the
OCS2007 by offering ubiquitous access from multiple access points –
PSTN, SIP hard clients, SIP soft clients, and supports video on Office
Communicator. It utilises software based Digital Signal Processors
(DSP’s), and has a standalone capability.
4. Microsoft Applications for UC - Microsoft Office Communications
Server 2007 (OCS2007) Standard and Enterprise Edition. These
include:
• OCS2007 Application Proxy Server - Required for Nortel MCM
• OCS 2007 Front End Server (FE Server) - Interfaces to
OCS2007 clients and provides them with multimedia features. It
communicates directly with Nortel MCM allowing for seamless
integration of the Communicator clients to Nortel telephony
services. Other functions include: User Services – Reverse
number lookup for incoming phone calls. User Replicator –
Extracts user phone numbers from Active Directory and Address
Book Service – normalises phone numbers to E.164 format.
• OCS2007 Mediation Server – The Mediation Server provides a
number of functions, including SIP signalling and RTP media
translations, SRTP encryption within OCS2007 and RTP/RTCP
to SIP Gateway Endpoints and OCS2007 clients. For transport
purposes, it translates SIP to TCP on the CS100E Gateway
side, and SIP over MTLS on the OCS2007 side. It is required for
media translation, converting to and from G.711 on the CS100E
Gateway side and RT Audio on the OCS2007 side. It also
connects clients outside the network to Internal Interactive
Connectivity Establishments (IICE) which then enables media
traversal of NAT and Firewalls
• OCS2007 Active Directory Server – Fundamental in a Microsoft
environment, Active Directory performs a number of tasks
including storing Global Settings and Groups necessary for the
deployment of OCS2007. It has a centralised database which
maintains Authentication and Authorisation services within a
domain and also assigns Policies to users
It is important to note that dependent on deployment options, Standalone or
Enterprise Edition on the OCS2007 for example, other components such as a
standalone SQL server may be required and also Nortel Application Switch
(NAS) for hardware load balancing.
So it is these two, up till now disparate and technologically distinct entities -the
telephony world of Nortel and Microsoft’s application environment - that the
Nortel Converged Office merges. This enables users to originate and receive

4. telephone calls over existing CS1000E phones from a Microsoft OCS2007
Desktop Client, as well as having the capability to make and receive PSTN
calls from this OCS2007 soft client when away from the office.
The benefits of Nortel Converged Office is it’s provision to users of a powerful,
feature-rich telephony and multimedia solution which improves worker
productivity and efficiency by integrating popular Microsoft Office applications
such as e-mail and Instant Messaging with VoIP Desktop Phones and Clients.
NCO Solution Basic
Architecture
NMC 5.0
Active Directory
NRS (SPS/SRS)
Mediation Server
MCM/Application Proxy
Server
CS1000E
IP Phones Office Communicator 2007
Front End Server
Nortel Microsoft
Solution Core Features and Functionality:
You can access the functionality of this solution in either of two modes:
Remote Call Control, for mainly office based users who use a deskphone, and
Telephony Gateway and Services, suitable for users who are perhaps more
mobile, allowing them to use their PC for voice calls.
So, Nortel Converged Office facilitates Remote Call Control (RCC) with SIP
CTI (TR/87) which provides full Microsoft Office Integration to control Nortel IP
phones from the Microsoft Office 2007 applications.
It also allows for Telephony Gateway and Services, where the Nortel CS100E
provides the Private and Public Telephony Network access for the OCS2007
Clients.
RCC (also known as “RCC-mode” or “phone-mode”) is where incoming calls
are “twinned” to the OCS2007 Client and the CS1000E phone. Users have
the flexibility to control Call Functions directly from Microsoft 2007
Applications – controlling the IP phone from the Communicator client for
example. The Nortel CS1000E Signalling Server performs the SIP CTI
(TR/87) functionality.

5. Outgoing calls in this mode can be initiated using click-to-call functionality
from the Office Communicator Client, (also integrated into the Msft Outlook
application) the call then being instigated from the phone.
Telephony Gateway Services (also known as “VoIP mode”) is where Nortel
Converged Office users have Business grade telephony services made
available to them by utilising the CS1000E switch as a SIP Gateway. The
CS1000E provides IP media conversion to the PSTN. In this scenario, users
can choose to use the OC2007 Client or the CS1000E phone. They also have
immediate access to Nortel provided dial plan, VoIP infrastructure, and
telephony features. A Personal Call Assistant (PCA) is required to support this
functionality. The PCA extends many of the Nortel CS100E features to the
OCS2007 Communicator, such as:
• Numbering Plan translations
• Call Detail Recording (CDR)
• Call Forward No Answer
• Attendant Recall
• Group Call

6. Also, phones are not required if the Office Communicator is available to the
users. This however has the effect of the full Enterprise telephony featureset
not being available to the user – only the basic telephony functionality
provided by SIP.
The Nortel Communications Server 1000E VoIP PBX is scalable to meet the
customer needs. An integral part of the solution is the Nortel Multimedia
Converged Manager (MCM) which ensures interoperability between the
CS100E and the OCS2007. Nortel Multimedia Conferencing (NMC) provides
SIP-based audio and video conferencing features.
The Nortel Converged Office provides users:
• Instant Messaging
• Enhanced Presence – NCO users can provide more info regarding
their own status; even when in RCC mode when the phone is on or off
hook for example. Users experience enhanced presence in Msft
applications as well as the Office Communicator.
• Group IM – Allows for conferencing of two or more parties. Group IM is
provided for by the Msft Conferencing Server
• Integration with Microsoft Office 2007 Applications (Word, Excel,
Outlook, Sharepoint)
• Microsoft Office 2007 Communicator
NCO Components
CS1000E – SIP Gateway
NRS (SPS/SRS)
SIP
Signalling Server/SIP
Gateway
pbxLink
SIP
Call Server
pbxLink
MCM/Application Proxy
Server
Media Gateways
SIP
RTP
RTP
End Users
PSTN
Another feature of the Nortel Converged Office solution is Integrated Unified
Messaging with Microsoft Exchange 2007.

7. Microsoft Exchange Server 2007 integrates e-mail, voicemail and fax into a
centralised location for users. Users access these messages within their
Office Outlook 2007 or Outlook Web access. Users are offered the advantage
of the interoperability features between the CS1000E Telephony Services and
the Unified Messaging Solution provided by the Msft Exchange Server 2007.
A few points of note: For Integrated Unified Messaging to Microsoft Exchange
2007 to work the only supported codecs are G7.11 and G7.29, and Exchange
Server 2007 must be configured as a static endpoint on the NRS as dynamic
registration is not supported in this instance.
In addition, for Message Waiting Indicator (MWI) functionality for OCS2007
users on soft clients, a third-party add-on is required, Geomant MWI 2007.
Solution Deployment Options:
Deployment considerations depend on the size and requirements of your
organisation, and there are various options on how the Communications
Server1000E and Nortel Converged Office could be deployed to satisfy user
criteria. A few options are:
CS1000E Single Site Deployment – This is a simplified deployment that is
easily managed and allows for future growth. It includes a CS1000E with
either Standard Availability or High Availability Call Servers, Signalling
Servers, Media Gateways and IP phones
CS1000E Multi Site Deployment – This includes multiple CS1000E’s and
supports Campus and geographically distributed (remote) customer sites.
It also includes Primary, Alternate and Failsafe NRS to provide a centralised
Dialling Plan. Each CS1000E supports Gateway access to the PSTN.
CS1000E Geographic Redundancy – The use of Survivable Media
Gateway’s (SMG) enhances the CS1000E reliability by allowing up to 50
geographically remote Call Servers to one Primary Call Server. These SMG’s
are configured with one Primary Call Server and/or two Alternate Call servers.
Secondary Call Servers allow for two levels of redundancy for the IP and TDM
devices assigned to it. Triple IP registration for redundancy is also provided
for by the SMG’s.
Where required, Campus Redundancy is also provided for: This is the ability
to Geographically divide a CS1000E High Availability over a campus
environment.
NCO Small Network – CS1000E deployment
In this scenario, deployment options may include a Standard Availability
CS1000E system, comprised of the basic components, a Signalling Server,
Media Gateway and IP phones.

8. NCO Small Network – OCS2007 Standard Edition deployment.
Deployments of this size are to support up to 5000 users and is
recommended to customers who do not require any redundancy. Typical
OCS2007 SE components would include an OCS2007 Application Proxy
Server running MCM, a Front End Server, a Mediation Sever and Active
Directory.
NCO – OCS2007 Enterprise Edition Medium and Large network deployment
considerations.
Recommended for enterprises with more than 5000 users and require High
Availability. OCS2007 EE components would include Active Directory, OCS
2007 Application Proxy Servers running MCM, Front End Servers, Mediation
Servers, SQL Servers and Nortel Application Switches.
Specifically for OCS2007 Enterprise Edition, two types of Pool configurations
are supported:
• Enterprise Edition Consolidated Configuration – Here, all the server
functionalities/Roles on each Enterprise Edition Server are combined
within a pool. This configuration would provide for simplified
management and deployment and also reduce the number of physical
servers required, while still maintaining High Availability for users.
However, reduced system performance on a per computer basis would
be experienced due server consolidation.
• Enterprise Edition Expanded Configuration – Each Server component
is deployed on a separate physical server/computer with many pools.
This High Availability configuration provides users with increased
scalability and maximum performance, however also increases the
deployment complexity and management.
Nortel Converged Office supports both OCS2007 EE Consolidated and
Expanded deployments.

9. NCO Architecture
CS1000E with MS Office 2007 Enterprise Edition Deployment
NMC5.0
Active Directory
NRS (SPS/SRS)
MCM/Application Proxy
Server
Nortel
CS1000E SQL Server Application
Mediation Server FE Server
Pools Switch
IP Phones Pools Pools
Pools
Users
Nortel Microsoft
A word to customers, integrators and solution providers:
We have outlined the components, deployment and advanced integration
options of the Nortel Converged Office solution. To extract the real benefits
from this type of technology, organisations have to spend time and money to
upgrade the basic communications infrastructure, to optimise the results of
what this Unified Communications solution brings together. So upfront, these
technologies may appear to be expensive if considered through the eyes of
accountants and financial types. But, these networks deliver more value every
day the organisation operates with UC enabled solutions.
Thus, people such line managers and staff using the system are presented
with the challenge of proving the value of this more complete solution.
If this bridge is successfully gapped, you will preserve profit margins and
maintain a competitive position in the market.
We here at Unified believe this so strongly, that it will support it’s customers in
this educational process, through white papers, technology presentations and
in some cases person-to-person assistance in sales calls.
But we pledge that if we see an installation that is high risk for from an
application point of view, we will steer you from it. Why? Because nobody –
you, your customer or Unified needs those complications.
And, while Unified Communications is new to most people and you and
customers may have many questions, we will endeavour to provide satisfying,
understandable answers.

10. For more information on the Nortel Converged Office, OCS or CS1000E
please contact gvlismas@unifiedgroup.co.uk
.