The document provides an overview of the Clearspan enterprise solutions guide, which is intended to advise implementers about deploying centralized voice services architectures in enterprises. It describes Clearspan as an enhanced unified communications system allowing enterprises to offer advanced communications applications over a VoIP network. Key aspects of Clearspan covered include its scalability, support for single or multi-site deployments, use of open standards, and integrated suite of communications applications.
8. Part I – Solution Overview
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9. 1 Purpose and Audience
The Clearspan Enterprise Solutions guide is intended for enterprise telecom
administrators or those who support enterprise communications networks (system
administrators and system integrators). This document describes how Clearspan is
deployed as a converged communications platform in the enterprise. It is designed to
advise implementers about the advantages, processes and requirements of deploying
centralized voice services architectures.
At the core of the Clearspan solution is BroadWorks, an open, standards-based, highly
resilient and easily managed software suite, capable of elegantly scaling to millions of
users. Deployed on industry standard server platforms, the solution delivers lower total
cost of ownership (TCO) by lowing implementation, operating, support and maintenance
costs. IT and Telecom managers will enjoy an easy-to-provision and easy-to-manage
solution that is extensible with many 3rd party applications, such as CRM and Microsoft
LCS.
In addition to offering a converged environment, Clearspan addresses an additional set of
problems inherent in traditional networks. Using the web, Clearspan provides a high
servicing component between the enterprise administrator and the user. User control and
configuration is provided via a standard web portal that augments basic phone
functionality to make existing services (for example, conference calling and call
forwarding) easier to use, and new services easier to deploy. For example, a user can
selectively forward calls from an office phone to a cell phone with a few clicks on a web
page or wireless PDA.
The Clearspan platform operates on a standards-based, modular architecture that uses
common protocols (such as SIP), open interfaces, and scalable, industry-standard
hardware. The open environment enables enterprises, as well as third-party service
developers, to rapidly introduce new features and launch new applications.
2 Overview
2.1 What is Clearspan?
Clearspan is an enhanced unified communications system that allows large enterprises to
offer advanced communications applications over a Voice over IP (VoIP) network. VoIP
networks consist of network elements that provide packet conversion, call control, and
applications. Clearspan provides call control and enhanced services for enterprise users. It
is developed on a standards-based, modular architecture utilizing common protocols,
open interfaces, and scalable, industry-standard hardware.
2.2 Why choose Clearspan?
There are many compelling reasons why an enterprise should choose Clearspan IP-PBX
communications platform:
A Fully Integrated Communications Suite
Clearspan provides a complete suite of communications applications. It offers not only
classic PBX-like services, but also a rich set of enhanced services including unified
messaging, interactive voice response, business conferencing and contact center. These
services are integrated into a single platform with a common web-enabled end-user
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10. interface, eliminating the need to deploy and integrate dedicated communications
platforms for each application.
N-Way Conferencing
Vendor D
Unified Messaging IVR - Vendor B
Vendor C
PBX - Vendor A
• Software-based solution
• Hardware-based multi-vendor solution
• Proprietary vendor hardware
• Off-the-shelf hardware
• Custom platform for each application • Single platform for all applications
• Poor user experience • Integrated user experience
• Proprietary graphical user interfaces • Web-based access
• Limited extensibility • Extensible service platform
• Proprietary legacy CPE • Standard SIP-based CPE
Figure 1 Fully Integrated Communication Suite
A Scalable Enterprise Communications Solution
Clearspan is a flexible unified communicatoins platform designed to meet the demanding
requirements of today’s large enterprises. At its core is a highly scalable call processing
architecture capable of serving enterprises as small as a thousand users, as well as the
ability to grow to a network serving hundreds of thousands of users without sacrificing
ease of management or reliability.
Single Site or Multi-Site Deployment Models
With Clearspan, service delivery is not bound to a physical site. Users can be deployed in
a simple single site network, or distributed across a multi-site enterprise without impact to
service functionality, capacity or performance. Clearspan can be deployed at a single site,
yet support users distributed across hundreds or even thousands of branch locations. To
better manage calls across a large multi-site enterprise, Clearspan includes a variety of
powerful site-based call routing and virtual private networking policies.
Disaster Proof Reliability
All Clearspan network elements can be deployed across geographically distinct locations
throughout the corporate communications network. This allows enterprises to deploy a
fully redundant data center in two geographically separate sites. In the event that a major
disaster disables the primary data center, end-users will still have full access to their
service profile through the redundant data center. With Clearspan, enterprises are
provided with carrier level five 9’s reliability.
An Open, Standards Based Platform
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11. Clearspan does not use any proprietary interfaces. When interfacing with access
equipment, Clearspan uses the Session Initiation Protocol (SIP). This allows enterprises
to choose from a broad range of standards-based phones, terminals, gateways and
peripherals that best meet their budget and end-user requirements. Finally enterprises
can choose a communications solution without fear of “vendor lock-in”.
Clearspan is also an open services platform, offering a rich set of application programming
interfaces that enable real-time computer telephony integration with enterprise
applications. Unlike legacy communications platforms, these interfaces leverage simple
XML-based transaction models allowing enterprises to rapidly integrate both real-time call
control and service management applications.
2.3 What is in the Clearspan Enterprise Solution?
At its foundation, a Clearspan based enterprise unified communications solution includes
the service delivery platform built around BroadSoft BroadWorks. This platform is
comprised of four separate network elements: the network server, the application server,
the media server and the web server. If conferencing is required, a conferencing server is
also included. These elements work together to deliver core call control, enhanced
applications and service logic. Typically Clearspan is deployed in the enterprise data
center. For high availability and disaster recovery solutions, the network elements can be
deployed across two physically separate data centers without impact to performance,
manageability or scalability.
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12. Figure 2 Enterprise Solution
To deliver these services to the end user, Aastra also incorporate session border
controllers, access devices and network gateways. End-user access devices include
access gateways, SIP phones and soft clients. Network gateways include PSTN
gateways using either FXO, CAS, or PRI based interfaces.
Aastra has assembled a set of “enterprise configuration kits” that itemize vendor-specific
packages of access and network equipment that can be reliably deployed with Clearspan.
Each kit is tested and validated so that it integrates seamlessly, providing a complete
communications solution.
2.4 Key Business Applications
The flexibility of the Clearspan solution, coupled with Aastra’s technology and partners,
enables enterprises to address a wide range of applications. Along with the following
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13. applications, enterprises may easily develop their own applications, features and
integrations with a commercially available software development environment.
The applications most often considered are:
Converged Communications – maximize end-user productivity by providing them a
fully integrated communications environment, enabling smooth interaction across
individuals and groups. With its tight integration with Outlook, click-to-dial, voice and
video, unified messaging, call center and conferencing, Aastra provides a ubiquitous
communication experience, independent of the endpoint device used.
Fixed/Mobile Convergence (FMC) - Whether users are using mobile or stationary
phones, they share the same experience. Because the features are separated from
the endpoints, Aastra can easily integrate any type of device, without additional user
licensing expense. With Aastra’s FMC solution, there is no reason to involve the
cellular carrier as all features supplied to the mobile client are independent of carrier
used.
Business (SIP) Trunking - allows enterprises to provide “IP Trunking” connectivity to
existing PBXs. Enterprises may deploy next-generation trunking and overlay features
while preserving legacy PBX investments and slowly migrating all locations to VoIP.
Aastra provides a best-in-class set of integrated features and end-user clients that anchor
each of these applications. Users experience a unified service regardless of location or
endpoint used.
3 Standard Deployment Models
Clearspan supports a variety of deployment models – from single site deployments to
geographically dispersed multi-site deployments.
3.1 Single Site Deployment Model
The picture below depicts a typical Clearspan single site deployment. In this example, a
large single building enterprise has deployed Clearspan to offer all voice services in the
network. The building has a standard LAN configuration with one or more wiring closets
on each floor. In each wiring closet are rack mounted Fast-Ethernet (100Base-T) layer 2
access switches – enough to serve all stations on the floor.
Access Device Connectivity
Not all desktops have to have SIP phones; legacy analog equipment is also supported. In
this example, a line access gateway is deployed in wiring closets on floors that have
analog handsets. The line access gateway serves to convert standard analog phones to
SIP signaling and RTP media traffic over the IP network. The line gateway connects to
the local Fast Ethernet switch in much the same way as an IP phone. If only a few analog
phones exist, an Integrated Access Device (IAD) may also be used.
Each wiring closet is interconnected to the core enterprise LAN using Gigabit Ethernet
where traffic is backhauled to the service infrastructure.
Service Infrastructure Deployed in Centralized Server Room
A fully redundant Clearspan system is deployed in a datacenter with a high-capacity IP
connection to the core LAN. Often this is the same room that houses all of the enterprise
data applications.
PSTN Connectivity
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14. Also in the datacenter are redundant PSTN gateways. The gateways connect to the local
PSTN switch using standard TDM interfaces – typically one or more T1s in North America,
or E1s outside of North America. The PSTN gateways connect to a layer-2 switch using
either a Fast Ethernet or Gigabit Ethernet connection. Clearspan controls all signaling to
and from the PSTN gateways.
Figure 3 PSTN Connectivity
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15. Clearspan Manages All Call Control
The picture below shows the system interfaces for a typical outgoing call to the PSTN. In
this example, the user employs a web-based click-to-dial application to originate the call. .
Figure 4 Clearspan interface to PSTN
It is important to note that all call control is handled directly by Clearspan. Signaling with
the SIP phones is carried over the IP network using the standards-based Session Initiation
Protocol (SIP). Clearspan also uses SIP to signal with the PSTN gateways to setup the
outbound call. Once Clearspan has established the call, RTP media is exchanged directly
between the SIP phone and the gateway.
3.2 Multi-Site Deployment Model
Issues with Large Multi-Site PBX Solutions
Although Clearspan easily supports large single-site enterprises, it is often chosen over a
classic PBX or IP-PBX solution for its advantages in large multi-site deployments. Many
traditional PBX solutions suffer from a number of issues when deployed in multi-site
enterprises:
• Capacity – multi-site enterprises are usually very large enterprises often as big as
a 100,000 users. Some traditional PBX solutions can typically handle up to 2500
users per system. Once this capacity limit has been reached, another system
must be deployed.
• Scalability – when a traditional PBX system has reached capacity, another
system must be deployed in the network. Adding multiple call control elements to
a voice network makes routing and translations rules complicated – and often it
requires deploying a full mesh network between all the PBX systems.
• Feature Limitations – some traditional PBX solutions are not designed to
seamlessly deliver features to users across multiple sites. Often features across
multiple sites have limitations or simply are not supported.
• Manageability – legacy PBX solutions are hard to manage as they often lack a
centralized multi-system management interface.
• Availability – some traditional PBX solutions have very weak redundancy
solutions – especially when applied to a multi-site enterprise. Usually,
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16. redundancy requires spares for each line card, so a fully redundant PBX solution
would require separate spares per site. This is an extremely expensive solution,
and is also difficult to inventory and manage.
• Cost – the cost of deploying and managing multiple PBX systems in a distributed
multi-site network is high.
Disadvantages of a Distributed Call Control Model
This approach of adding PBX systems to the network in order to meet capacity can be
characterized as a “distributed call control model”. Often these systems have geographic
limitations that require the PBX system to be deployed close to the devices that it controls.
Consider a retail enterprise case study consisting of 1600 sites as depicted in the diagram
below:
Figure 5 Distributed Call Control Model
In this example, a popular IP-PBX solution was analyzed. To meet the requirements, the
solution required 33 separate call control data centers, each with their own distinct PBX
system. Each of the 33 PBX systems then needed to be interconnected and provisioned
with routing and translation logic about each of the other 32 PBX systems in the network.
The solution looked more like a network of 33 disparate enterprises, than one large
integrated solution.
Clearspan is Ideal for Multi-Site Enterprises
Clearspan was designed to address all of these multi-site issues not only for classic PBX
services, but also for the complete suite of voice applications including conferencing,
unified messaging, IVR and contact center services. This makes Clearspan an ideal
choice for large multi-site enterprises.
Clearspan can be characterized as having a logically centralized call control model. The
diagram below depicts how the same retail enterprise described above would be served
using Clearspan:
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17. Figure 6 Clearspan Call Control Model
With Clearspan, the number and complexity of sites may be greatly reduced. Centralized
call control enabled this enterprise to share a geographically redundant platform, reducing
maintenance costs, support costs and total cost of ownership.
Unprecedented Capacity and Scalability
In this deployment, all 1600 retail sites and hundreds of thousands of employees have
their services delivered through a single pair of Clearspan servers in geographically
redundant data centers. This is possible because, unlike traditional PBX solutions,
Clearspan has no limitations on the number of sites or the number of subscribers in each
site. The diagram below takes a closer look at a typical multi-site Clearspan deployment
model:
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18. Figure 7 Clearspan Multi-site Deployment Model
Voice Enabled Wide Area IP Network
Traditional multi-site PBX solutions require dedicated trunks between each site. These
solutions often require a fully meshed set of interconnects in order to optimize call routing.
Because Clearspan is a voice over IP solution, it can leverage the existing core wide area
IP network that already interconnects enterprise sites for data applications, as shown
above. It is important to note that the quality of service over the IP network must be
managed, as it will be used for both call signaling and media traffic between sites.
Precedence must be given to voice traffic over data traffic entering the network.
Geographic Data Center Redundancy
Voice service is a critical business application –enterprises cannot function if the voice
network is down. If all call control is provided from a single data center on the enterprise
network, there is a risk of total network outage in a disaster scenario. To meet enterprise
disaster recovery requirements, Clearspan supports geographic redundancy. Instead of
installing all network elements in one dedicated data center, Clearspan allows the
redundant elements to be installed in a separate geographically redundant enterprise data
center. Although these network elements are installed across two physically separate
sites, they are still managed as one logical system – configuration and provisioning
changes are automatically replicated between data centers. This approach provides an
enterprise with carrier grade five 9’s reliability.
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19. Optimized PSTN Inter-working and Expense
Interconnections to the PSTN are an expensive recurring cost to the enterprise. In a multi-
site enterprise, it is important to minimize the number of direct connections to the PSTN
and leverage the wide area network for intra-site calls whenever possible. Clearspan will
always route calls over the core WAN, utilizing VoIP whenever possible.
Clearspan also has routing policies that allow enterprises to leverage their PSTN gateway
deployments. For instance, in the diagram above, Branch Office A has a PSTN gateway
in local calling area 1 (LCA-1). This PSTN gateway is not only used for local calls by
users in Branch Office A, but also Branch Office B. Similarly, Branch Office D in local
calling area 2 (LCA-2) also serves users in Branch Office C.
To optimize hop-off costs to the PSTN, Clearspan can choose the best gateway route for
a given caller and called number. For instance, if a user in Branch Office D (LCA 2) calls a
number that is LCA 1, Clearspan will route the call over the WAN and through the PSTN
gateway that is hosted in Branch Office A, where it will be delivered as a local call. This
provides for least cost routing of public calls over the private network.
Often a large enterprise will negotiate a reduced long distance rate with an inter-exchange
carrier. The rate will apply to all calls made out of the PSTN gateway hosted in the
primary data center (headquarters) or an alternative backup data center (division office).
Clearspan can be provisioned with routing policies that will select the PSTN gateways in
the data centers for all long distance calls from any of the enterprise sites.
Site Independent Feature Functionality
Unlike some traditional PBX solutions, Clearspan services are not bound by physical site
boundaries. In the network above, users in one site can belong to service groups with
users in any of the other sites. For instance, a user in Branch Office B can belong to a
hunt group with users in Branch Office C and users in Headquarters. The same user can
act as an agent with one or more call centers in the network – regardless of where the call
center pilot number is hosted. Relocating users from one site to another is a simple web
based operation. This capability allows enterprises to reduce employee redundancy and
improve responsiveness.
Smart Sites – Remote Survivability Solutions
Because Clearspan is based on the Session Initiation Protocol (SIP) standard (a peer to
peer protocol) as opposed to a master slave protocol like MGCP or SCCP, sites can be
deployed with remote survivability support. These “smart sites” are able to detect a WAN
outage. When an outage occurs, the local access equipment provides a set of basic
services including: intra-site extension dialing, call hold/retrieve, call transfer, and 3-way
calling. If a PSTN gateway is available on the site, then incoming and outgoing PSTN
calls can also be delivered.
Remote Worker Support
Clearspan allows remote workers or telecommuters to have access to their complete set
of voice services while working from home or on the road. Clearspan supports both
“broadband” and “narrowband” remote worker solutions.
With a broadband connection, users get service directly through their IP phone or soft
phone connected to the corporate network over a VPN connection. With a narrowband
connection, users get service through their local PSTN connection. Incoming calls are
forwarded to their “remote-office” number, while outgoing calls are initiated through a web
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20. based call back mechanism. Both solutions allow enterprises to manage outgoing calling
plans and centralize billing for all remote users.
Ease of Management
One of the biggest advantages of Clearspan over some traditional PBX solutions is
manageability. While other PBX solutions often require routing policies and translations to
be replicated across multiple systems, routing policies and translations in a Clearspan
network only need to be provisioned once.
Clearspan also incorporates a multi-level web portal for user and service management.
This portal allows enterprises to administer company wide group services, define sites,
and manage resources such as devices, phone numbers, and services across the
corporation. The department level portal allows delegation of user moves/adds/changes
(MACs) to a designated department administrator. Enterprise administrators have the
flexibility to manage users across all sites remotely, or delegate user-management
responsibility to individual site administrators.
Finally, the user portal empowers end-users to take control of their service profile through
the web. Users can select their incoming and outgoing calling preferences directly on the
web. From classic services like call forwarding, call rejection, and 3-way calling, to
enhanced services like remote-office, voice mail and business conferencing, the web
portal makes it easy for end users to access their services anywhere on the corporate
network.
4 Key User Applications
All Clearspan features run on the same platform, use a common interface, and can be
added to the network at anytime. The sections below briefly describe a few of the key
applications provided by Clearspan. For a complete description of all of the features and
their functionality, refer to the latest “Clearspan Product Overview” for details. All of these
features are software based solutions and require no extra hardware to deploy.
4.1 Clearspan Communicator Family
The Clearspan Communicator family enables end users to convert their desktop computer
into a fully functional phone. This client offers advantages over other client softphones as
a result of the integration with the Clearspan system platform and tailored features-
functionality to Clearspan applications.
4.1.1 Clearspan Communicator
The Communicator client is an audio-only client that provides a feature-rich desktop
interface to make and receive calls as well as execute enhanced features. The
Communicator has access to Clearspan’ many advanced VoIP features including
screening and messaging/voice mail integration.
As an integrated device with the Clearspan platform, enterprise administrator are able to
auto provision the client, provide automatic updates, and maintain version control
seamlessly through the Application Server. The Communicator is capable of supporting
G.729a protocol. The Communicator allows users to utilize the client as a primary or
secondary phone device. Clearspan supports this via server features that enable both
devices to register to the same user account and directory number (DN)/direct-inward
dialing (DID) number.
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21. The Communicator is available in English, Spanish, and Simplified Chinese, in addition to
having multi-language support through the Clearspan platform.
4.1.2 Clearspan Communicator - Multimedia
The Clearspan Communicator - Multimedia provides all the capabilities of the audio-only
Communicator and adds high quality multimedia transmission. With the Communicator -
Multimedia, a user’s desktop computer can function as a full-feature multimedia
communications device.
Figure 8 Clearspan Communicator Multimedia Menu
While Clearspan integration offers considerable value for the audio-only client, the benefits
are even further expanded with the addition of video. First, the video codec negotiation is
somewhat more complicated than audio-only codec negotiation. Clearspan pre-
integration limits the issues associated with video codec negotiation, simplifying
deployment and reducing support calls and customer issues. Second,
pre-integration with the video client enables separate routing of voice streams over
traditional handsets while the video signal is connected to the video client. Thus, users
can enjoy features of their desk handsets such as a high-fidelity speakers and
microphone, along with the multimedia experience available from the desktop client.
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22. 4.2 Clearspan Assistant Family
The Assistant family is a suite of products that helps, or “assists”, end users to manage,
control, and configure their phone. In a compact and extremely useful user interface,
Clearspan Assistant provides users with an easy way to answer, transfer, and dial calls,
search enterprise, personal, or Outlook contacts directories, and quickly enable/disable
call settings such as Call Forwarding, Do Not Disturb, and Simultaneous Ringing with a
click of a mouse.
4.2.1 BroadWorks Assistant – Enterprise
The BroadWorks Assistant is a feature-rich, integrated toolbar that enables users to make
and accept telephone calls, and change telephone settings, from within Internet Explorer
and Outlook. The toolbar delivers the following features and benefits to users:
Complete call control capabilities, including making, receiving, transferring and holding
calls
Right-click to dial on highlighted phone numbers within web pages
Easily change telephony service settings such as Simultaneous Ringing, Call
Forwarding All, Call Forwarding No Answer, Call Forwarding Busy, Do Not Disturb,
Remote Office, VM User, Logged-in Status
Add Microsoft Outlook contact vCards for new incoming calls
Outbound click-to-dial from Outlook contacts
Group, enterprise and LDAP directory browsing
Call notifications with caller ID from Clearspan
See who is calling based on a contact list in various Clearspan directories
View call history
User help functions available during any operation with an HTML user guide built into
the application
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23. Figure 9 Clearspan Call Center - Agent
Figure 10 Clearspan Call Center - Agent Menu
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24. 4.2.2 Clearspan Assistant - Mobile
Clearspan Assistant - Mobile is a feature-rich, easy-to-use mobile application that is fully
integrated with the Clearspan platform. It is an integrated Nokia E-series mobile handset
application that enables users to originate Clearspan-routed telephone calls, modify their
telephone settings, view their corporate directory, and have access to their call logs.
Clearspan Assistant - Mobile is a carrier class, lightweight mobile application for everyday
users that delivers the following features and benefits to users:
Provides access to a corporate directory
Addresses the needs of corporate, small business and small office/home office users
Receives voice mail notifications
Easily change telephony service settings such as Simultaneous Ringing, Call
Forwarding All, Call Forwarding No Answer, Call Forwarding Busy, Do Not Disturb,
and Remote Office
View call history
Place calls from a mobile phone but have it appear like as if the user is calling from
their office line
Manage only one phone number and voice mail account
Create international profiles
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25. 4.3 Personal Web Portal
The Personal web portal provides individual users with the ability to configure and manage
a host of traditional and advanced telephony services. Each user is empowered with the
control and flexibility to easily configure their services to meet their unique needs. Users
no longer have to remember any star codes or complex procedures to configure their
services, as is often the case with legacy systems. Rather, Clearspan improves personal
productivity by leveraging the web to make services understandable and actually useable.
Users can customize their services to follow them anywhere, whether at work, at home or
on the road. For example, the Call Notify service (shown below) enables users to indicate
which incoming calls they want to be notified of, and during which hours of the week.
They can also choose to have their notifications sent to their mobile phone or e-mail
address.
Figure 11 Clearspan CommPilot Personal Portal
After logging in to the personal web portal with his/her user identity and password, a user
can activate, deactivate, and modify the parameters of his/her own services, including:
Call Forwarding (Always, Busy, No Answer, Selective), Simultaneous Ring, Do Not
Disturb, Selective Call Acceptance and Rejection, Anonymous Call Rejection, Priority and
Distinctive Ringing, Calling Line ID Blocking, Voice Messaging Notification, Voice
Messaging to E-mail, Personalized Name Recording, and Remote Office. The left
navigation area lists services and features available to the user.
The Web Portal updates features and configurations in real-time, providing utility and
convenience. Convenience is important for features that are frequently updated by users
such as the call-forwarding suite. The web interface also provides a means for making
sophisticated entries and configurations, very difficult to replicate through a standard voice
portal. For example, in addition to specifying phone numbers for service treatments,
Clearspan enables users to provide SIP URLs, feature access codes, and/or speed
codes. Selective call treatments can be defined for parameters that include line ID status
such as PRIVATE, and UNAVAILABLE, along with the more common IDs such as
ANONYMOUS.
The following features can be provided with the CommPilot Call Manager:
Dial/Redial (click-to-dial) – Enables a user to enter and dial a number, dial directly
from a drop-down Phone List (Group, Personal, or Call Log) or from Outlook or LDAP
tabs, or click the Redial button.
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26. Transfer – Enables a user to redirect a ringing, active, or held call to another number
or directly to voice mail. Before transferring the caller, the user can choose to consult
with the third party first or establish a three-way consultation.
Send to VM – Enables a user to transfer calls to voice mail.
Talk – Enables a user who is already engaged in call to answer another waiting call.
When available, Calling Line ID is displayed with caller’s name and number.
Hold – Enables a user to place an existing call on hold for an extended period of time,
and then retrieve the call to resume conversation. While the calling party is held, the
user can choose to make a consultation call to another party.
Conference – Enables a user to establish a three-way call involving two other parties.
Hang Up – Enables a user to disconnect a call that has been answered.
Hot Links – Buttons are provided to enable a user to turn on/off frequently-used
services such as Call Forwarding Always and Do Not Disturb. Alternatively, if
CommPilot Express has been configured, the user can change their CommPilot
Express status (for example, Available, Busy, Unavailable) by choosing from a drop-
down list.
System Buttons – Buttons are provided to enable a user to send an e-mail for
technical support, get context-sensitive online help, and configure the CommPilot Call
Manager.
Figure 12 Clearspan Call Manager
The Call Manager is used to augment the functions of a standard phone. It provides an
alternative user interface for enhanced services, replacing flash-hook and star codes. It is
not intended to replace the phone or be a stand-alone substitute for basic call functions.
Calls can be initiated and manipulated using the phone or the web interface. The audio is
transported through the phone, not via the user’s computer.
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27. 4.4 Unified Messaging
Clearspan messaging provides all of the features of a traditional voice messaging solution,
plus:
• Message delivery to any specified email account.
• Message waiting notification delivered to the phone and to any specified mail or
Short Message Service (SMS) account (e.g. cell phone).
• Integration of messaging capabilities with Clearspan services (call back, transfer,
find me / follow me services, escape to extension, voice portal, etc.).
Incoming calls to the user are sent to voice mail upon reaching a busy or no-answer
condition. The caller is then played a greeting. There can be different greetings for busy
and no-answer conditions and all greetings can be partially or fully customized by the user:
• Default busy greeting
• Default busy greeting with name
• Custom busy greeting
• Default no-answer greeting
• Default no-answer greeting with name
• Custom no-answer greeting
The caller can then leave a message or press 0 to transfer to an attendant. The attendant
is configurable by the user and can be any valid phone number. If the caller leaves a
message, he/she has access to the following functions:
• Long message warning tone
• Set the message status to urgent and/or confidential
• Review the message and erase, record it again or deposit it
• Users can also configure their voice mail service to serve other phones, like a cell
phone. With this capability, users can forward any phone to the CommPilot Voice
Portal phone number and have the calls be sent directly to their mailbox greeting.
This powerful application allows employees to use a single Clearspan voice mail
system for their office phone and mobile phone – they do not need to manage
multiple voice mail accounts separately.
Voice messages are stored on standard email servers (POP3, IMAP4, Microsoft
Exchange Server) as WAV audio files attached to emails.
Users can retrieve their emails from their main location, from a third-party location or from
any standard email client. When retrieving emails from their location, users simply dial the
CommPilot Voice Portal phone number (or extension). The system prompts the user for
their passcode. After entering the passcode, the user is informed of the mailbox status
(how many urgent, new, expired, and saved messages) and can review the messages
through a menu. While reviewing the messages, users can play the message envelope,
jump to next or previous message, skip ahead, skip back, pause, repeat, erase, save,
reply, call back, forward, compose and send to a user or a distribution list.
When retrieving emails from an email client, the user simply configures the client to collect
email from the email server where the messages are stored. Messages are retrieved as
WAV attachments to emails and can be listened to with standard audio software.
Messages received as email can be manipulated like any other email (stored, forwarded,
replied to, etc.). Some enterprises prefer to keep “carbon copies” of all voice mail
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28. messages received, for regulatory or security reasons – this can be done easily on
Clearspan with just a few clicks.
When the user receives new messages, they can be notified by standard message waiting
indication mechanism (stutter dial tone and message waiting lamp). Users can also
request a notification to be emailed to a specific location, like a cell phone, when a voice
message is received.
4.5 Contact Centers
Clearspan provides support for basic contact centers, allowing business agents to receive
incoming calls from a central phone number. Using this service, a business can establish
technical assistance lines, customer support numbers, or order-taking centers. Multiple
contact centers can be supported per business. Incoming calls to a contact center are
presented to the next available agent.
The Contact Center is based on Automatic Call Distribution (ACD) service to provide a
complete, business-ready application. Hence, contact centers inherit all of the
characteristics of the Hunt Group service and are also provided with sophisticated call-
handling features like queuing, music on hold, etc.
Figure 13 Clearspan Contact Center Menu
Clearspan expands the capabilities of legacy contact centers by delivering a true remote
agent solution, allowing call center agents to be geographically distributed. Therefore
agents can attend calls from home, a satellite office, or any other location served by
Clearspan in a transparent fashion
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29. .
Figure 14 Clearspan Contact Center
Clearspan Contact Center functionality can be combined with other Clearspan Call
Completion services to ensure that all incoming calls are serviced expeditiously under any
network condition and at anytime.
Voice mail – If there are no agents to handle an incoming call or the call goes
unanswered for a specified amount of time, the call can be forwarded to a contact
center voice mailbox.
Night service – Calls received after-hours or on non-business days receive a service
menu of options allowing a caller to leave a voice message or transfer to an
emergency number.
Multiple call distribution policies – Incoming calls are handled according to the
selected policy, which include uniform call distribution, linear hunt group, circular hunt
group, and simultaneous ringing.
Call queuing – When all call center agents are busy, incoming calls can be queued
until they can be presented to an available agent.
Queue escape – Callers who are queued can press a key to be sent directly to the
contact center voice mailbox instead of waiting for an available agent.
Overflow – When a contact center cannot accept any more calls, incoming calls can
be forwarded to an overflow phone number.
Statistics – Statistics are generated for each contact center group and can be viewed
by the group administrator via the web portal.
Service integration – Any Clearspan personal service can be assigned to a contact
center phone number to customize the contact center group. This includes services
such as Call Forwarding, Call Notification, Call Screening, and Voice Messaging.
Queue flushing – When all agents in the contact center group log out, queued calls
are automatically sent to the contact center group voice mailbox.
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30. Outlook contact integration – vCards from the agent’s Outlook or Exchange contact
database pop up for incoming calls.
Agent log in/log off – Agents can log in and out from the group so that calls are only
presented to agents who are on duty.
Screen pop-ups – Incoming calls pop up on a web screen showing information
associated with the incoming call. A group-specific URL is accessed for each call.
Configurable Music on Hold – The queued callers are provided with music or
advertisements between periodic announcements.
4.6 Auto Attendants
The Auto Attendant provides enterprises with a powerful and flexible tool to field inbound
calls and deliver them to the intended destination through interactions with the caller. The
Clearspan Auto Attendant is an integral part of the product offering and does not require
any third-party equipment.
The Auto Attendant is reached by dialing an associated phone number or an extension.
Once connected to the Auto Attendant, the caller is played a greeting that provides a
menu of options to complete call routing.
The menu, which is configurable by an enterprise administrator, can provide up to nine
options to the caller, including:
One-key dialing – The caller presses a pre-defined DTMF key to reach a particular
phone number or extension within the group. This option is also used to build
multilevel IVR menus.
Operator dialing – The caller presses a pre-defined DTMF key to reach an operator.
Name dialing – The caller spells the name of the intended party using the numerical
DTMF keypad. Upon identifying a unique match, the caller is played the name of the
called party and is then transferred.
Extension dialing – The caller enters the extension of the intended party through the
numerical DTMF keypad. Upon collecting the full extension, the caller is played the
name of the called party and is then transferred.
The moves, adds, and changes for users in a group are automatically available for the
Auto Attendant name dialing and extension dialing functions. Access to users currently in
the group is always available.
The Auto Attendant uses the multi-location enterprise capabilities of the Clearspan
platform to transparently support geographically distributed groups. The Auto Attendant
supports users with a Direct Inward Dialing (DID) number as well as users without an
external public directory number. These users originate calls as usual and the Auto
Attendant allows them to receive external calls. Calls made to the Auto Attendant use the
routing capabilities described above to terminate calls to the appropriate user.
This support provides greater flexibility for a group administrator to create and delete users
and in many cases reduces the costs associated with obtaining DID numbers. Clearspan
can also offer speech-based Auto Attendants, which use a speech IVR instead of a
DTMF-based IVR (“call Joe on his mobile”).
4.6.1 Clearspan Receptionist
The Clearspan Receptionist is a carrier class IP telephony attendant console for use by
receptionists, or telephone attendants, who manage and screen inbound calls for
enterprises. The BroadWorks Receptionist is a feature-rich desktop application that is fully
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31. integrated with the Clearspan platform. The application delivers the following benefits to
users:
Easy-to-use design that follows the natural work “flow” of a call from the top to the
bottom of the screen.
Intuitive business processes, as only “valid” options are presented to the attendant.
Professional call handling as critical information is available in real time.
Accurate delivery of messages via a one-step process when people are unavailable.
The BroadWorks Receptionist can be used under a number of different operational
scenarios. These scenarios include:
After Hours – Allows operators to automate switching from day to night mode.
Call Center Queue – Allows operators to monitor and control calls in a Call Center
queue, and to manage their availability status.
Hoteling – Allows multiple part-time operators to share a single log-in sequence when
they change shifts.
Low Traffic – Single receptionist answering one or more dedicated main line
numbers.
High Traffic – More than one attendant console managing multiple dedicated main
line numbers.
Network Attendant Console – Geographically dispersed operators supporting each
other in an enterprise configuration.
Multi-tenanted Offices – One or more operator answering calls on behalf of different
organizations.
Optional Voice Mail Transfer – Operator has the added ability to transfer calls to
voice mail for contacts in a group/enterprise that are busy or unavailable.
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32. Figure 15 Clearspan Receptionist Menu
4.7 Web Conferencing
Clearspan supports a variety of business conferencing services, including meet-me
conferencing, reservationless conferencing, automated dial-out conferencing,
collaboration tools, and more.
Web Conferencing enables the set up, use, and monitoring of n-way conferences via a
web interface. Both internal and external participants can use a conference bridge once it
has been set up. A single
The Conferencing service includes the following features:
Audio and web conferencing
Scheduled, recurring, reservation-less, and ad-hoc
Meet-me dial-in numbers
Web collaboration
Share Microsoft PowerPoint, Excel, and Word files (extensions are automatically
checked by Clearspan for validity)
Secure SSL and password protection
Web browser viewable, no client required
Optional click-to-download of web presentations
Moderator control
Dial-out capability
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33. Mute, hold, drop, and add participants
DTMF and web portal interfaces
Roll call (service can record and announce participants’ names as they join)
In-call functions
Hand raising (muted participants can request the conference leader to un-mute
them temporarily)
Optional leader
PIM integration
Automated e-mail invitations and Outlook calendar entries
Reporting
Web-based reporting
Department and project codes
Recording
Recording and playback of individual conferences (the CDR can account for
recording duration)
Access code generation
Automatic, pre-assigned, or user-defined
Figure 16 Clearspan Conference
Figure 17 Clearspan Conference Call Menu
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34. 4.8 Clearspan Deployment Studio
The Deployment Studio facilitates the customization, deployment, and management of
Clearspan Assistant, Assistant - Enterprise, Receptionist, and Call Center -
Agent/Supervisor desktop client software by enterprise providers. Providers can configure
a variety of client settings, such as branding, networking, localization, and additional
pre-defined settings, for Assistant, Assistant - Enterprise, Receptionist, and Call Center.
The Deployment Studio is required to deploy all Clearspan clients.
Enterprise providers proceed through an intuitive GUI to fully customize their client
applications to suit their specific requirements.
5 Integrating with Legacy Equipment
This section describes solutions for integrating Clearspan with existing enterprise voice
networks. This is often required in multi-site enterprises with a large investment in legacy
voice equipment. The services provided by Clearspan complement the services provided
by the existing solution. Equipment on the enterprise site communicates with Clearspan in
the enterprise data center. Solutions are described for enterprises with existing Private
Branch Exchanges (PBXs).
5.1 PBX Solution (SIP Trunking)
A Private Branch Exchange (PBX) is a private telephone system that provides on-
premises dial service and connections to the PSTN. A PBX offers call control features
such as call waiting, call transfer and conferencing. Most PBXs can interface with other
communications applications such as auto attendant, voicemail, automatic call distribution
and call accounting. Many PBXs use proprietary phones, since a significant portion of a
PBX sale involves handsets.
PBXs typically serve medium to large enterprises locations. Typically, each user has a
dedicated line. For outgoing calls, the PBX switches calls from a user line to a trunk
connected to the PSTN. For incoming calls, a PBX switches calls from a trunk connected
to the PSTN to a user line. PBXs provide both personal and group based services. They
are popular in enterprises where employees require direct dial access.
5.1.1 Network Layout
A PBX gateway is used to inter-work a legacy PBX with Clearspan. The gateway provides
trunk interfaces for connectivity with the PBX and Ethernet interfaces for connectivity with
the LAN. The PSTN interfaces are via CAS or PRI trunks. On the Clearspan system, the
address of the gateway connected to the PBX is setup as a routing element within a Voice
VPN enterprise group.
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35. Figure 18 Clearspan Network Layout
As shown, the PBX connects to the GW via CAS or PRI trunks. The gateway is connected
to the corporate LAN via one or more Ethernet interfaces.
5.1.2 Services
To illustrate how the Clearspan services can be used to complement the services
provided by a legacy PBX, an example of a typical enterprise is used. In this example, an
enterprise has a PBX serving telephones and/or fax machines with a T1 PRI trunk
connected to a GW.
In this example, calls can be delivered to the GW with or without direct inward dialing
(DID). If DID is used, then individual phone numbers are assigned to each user. This
allows services to be provided on a user basis. If DID is not used, then there is a main
phone number for the PBX. Clearspan delivers all incoming calls to the main number,
which is associated with an attendant or auto attendant. The attendant then delivers the
call to individual lines connected to the PBX. Note, most PBXs typically support both DID
and non-DID access simultaneously. Some users will use DID and some will not.
5.1.2.1 Services for PBXs with DID
Some of the basic personal services provided by Clearspan are also provided by the PBX,
such as call transfer, call forwarding, extension dialing, etc. Clearspan complements these
basic services, providing additional enhanced personal services, including:
Service Usage
Anonymous Call Rejection Deny anonymous incoming calls before reaching the PBX.
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36. Service Usage
Call Forwarding Selective Forward certain incoming calls before reaching the PBX.
Call Notify Log all incoming calls before reaching the PBX.
CommPilot Call Manager Provide for web based call control functions.
CommPilot Express Customized incoming call management.
LDAP Directory Integration Integrate with enterprise directory.
Outlook Integration Integrate with Outlook or Exchange Server.
Remote Office Provide support for tele-workers and remote offices.
Selective Call Acceptance Accept only certain incoming calls before reaching the PBX.
Selective Call Rejection Deny only certain incoming calls before reaching the PBX.
Simultaneous Ring Ring the PBX user in addition to multiple external numbers.
Voice Messaging Hosted, centralized voice messaging.
Group services can also be used with PBXs with DID support. Group services that are
typically assigned include:
Service Usage
Account and Authorization Track and/or authorize all outgoing calls made from the PBX.
Codes
Attendant Console Provide hook status for off network calls to and from the PBX.
Auto Attendant Provide automated attendants for PBX users.
Call Centers Provide call centers for PBX users.
Calling Group Identity Provide the enterprise identity, instead of the individual line identity, for all
Delivery outgoing calls made from the PBX.
Hunt Groups Provide hunt groups for PBX users.
Incoming Calling Plan Block certain types of incoming calls made to the PBX.
Outgoing Calling Plan Block certain types of outgoing calls made from the PBX.
Voice Portal Provide a dial in interface for service interaction and management.
5.1.3 Services for PBXs without DID
When DID is not available, services are provided on an enterprise wide basis (main phone
number), not on a per user basis. Clearspan provides hosted, enhanced services that
complement those provided by the PBX, including:
Service Usage
Call Forward No Answer Forward unanswered calls to an auto attendant or enterprise voice
mailbox.
Call Forwarding Selective Calls received after hours or on the weekend are forwarded to an auto
attendant, enterprise voice mailbox or remote location.
Call Notify Calls to the main number are logged via email notifications.
Calling Line Identity Delivery Provide caller number and name for incoming calls.
Selective Call Rejection Nuisance calls to the main number are blocked.
Voice Messaging Provide an enterprise voice mailbox or individual voice mailboxes. This
works in a similar manner to a KTS. See KTS Solution for more details.
Group services can also be used with PBXs without DID support. Group services that are
typically assigned include:
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37. Service Usage
Account and Authorization Track and/or authorize all outgoing calls made from the PBX.
Codes
Calling Group Identity Provide the enterprise identity, instead of the individual line identity, for all
Delivery outgoing calls made from the PBX.
Outgoing Calling Plan Prevent certain types of outgoing calls made from the PBX.
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38. Part II – Solution Components
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39. 6 Clearspan Service Delivery Platform
This section describes the Clearspan platform in more detail. It provides specifics on each
Clearspan server as well as the preferred hardware platforms. In addition, it provides call
flows showing how the components interact.
6.1 Network Elements
Clearspan is composed of the following servers:
Application Server – provides call processing, service logic, endpoint management
and service management
Network Server – provides policy based translations and routing, subscriber location
directory and media server selection
Media Server – provides specialized media resources, including media recording,
media playback, DTMF digit detection, three way conferencing and media relaying
Web Server –supports Clearspan system web interfaces and additional external
interfaces. The Web Server supports the Personal Web Portal and Call Manager via
HTTP, as well as the BroadWorks Open Client Interface for the Assistant and
Receptionist applications.
Conference Server (optional) – provides enhanced audio and web conferencing.
PM Server – monitors the health, performance and reliability of the Clearspan
system.
Client Management System (CMS) – provides the central point to control the
functions associated with the configuration, deployment, and activation of user profiles
and templates for endpoints or clients.
Together, these components enable a wide array of personal, group, and network
services including PBX equivalent services, messaging, attendants, interactive voice
response, call distribution, site networking, conferencing and desktop integration. Each
server is described in more detail below.
6.1.1 Application Server
The Application Server is a service delivery platform responsible for the execution and
management of enhanced personal and group services. Application Server functions
include management of network traffic, handling of signaling interfaces, and logical
execution and management of services. The Application Server comprises a database,
the ServiceOS™ abstraction layer, and protocol stacks.
The Application Server supports the Session Initiation Protocol (SIP) as the
communication protocol with VoIP equipment, including:
Access Equipment – SIP Phones, Analog Line Gateways, WiFi Phones, Soft Clients
Network Equipment – PSTN Gateways, PBX Gateways, Session Border
Controllers, Edge Elements
Other Servers – Network Servers, Media Servers, Conferencing Servers, Third Party
Servers
The Application Server provides secure access to subscribers and services for
management, administration, provisioning, and configuration. The associated web portals
can be customized for different customer groups, based on the subscribed-to services of
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40. those groups. With various levels of security and accessibility (system provider, enterprise
administrator, group administrators, department and end-user), secure access is granted
not only to the system, but also to the correct level of privileges. Different users are
directed to the applicable screens with proper security and real-time information.
Information is retrieved from the database and displayed in real time.
Figure 19 Application Servers
Application Servers are deployed in pairs, where one servers acts as the primary server
and the other as the secondary server. Under normal operation, the primary Application
Server will manage all call processing and endpoint management. User modifications,
additions and deletions are replicated across the database of both the primary and
secondary Application Server, making all service and user profiles available on both
servers. Database replication is done in real-time, as additions and modifications are
made. Thus, both the primary and secondary servers have access to exactly the same
database.
In the event that the primary server fails, or is simply inaccessible from one or more
endpoints in the network, then those endpoints will be able to route their calls through the
secondary server. The failover time is the time it takes an endpoint to retry after a non-
response to the secondary server. This is typically engineered to be less than 1 second.
This type of redundancy may be geographically distributed; protecting against server
failures as well as against IP networking failures (e.g. router and circuit failures).
Application Servers are hosted on IBM servers, running the Linux operating system. Each
server connects to the VoIP network using 10/100BaseT Ethernet interfaces. Multiple
interfaces are available supporting a wide variety of IP network configurations. No
specialized hardware is required.
6.1.2 Network Server
The Network Server enables system providers to centrally manage network-related
applications within their network. This includes public translations and routing capabilities
such as least-cost routing, as well as enterprise-focused network applications such as
voice virtual private networks (VPNs).
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41. The Network Server allows construction of massive next-generation voice networks by
assisting with the scaling of IP telephony networks and offloading subscriber-specific
routing functions, allowing softswitches to focus on core call state management for
trunking media gateways. The Network Server also acts as a platform for network-based
enterprise applications such as private dial plans, and supports passing of non-numerical
characters like * and # to the network so they can be used to trigger functionality in other
networks.
The Network Server optimizes network resource utilization by providing the capability to
selectively route calls to geographically dispersed resources, thus maximizing network
bandwidth utilization. For example, the Network Server can manage Media Servers as a
single network-wide pool of resources and, at the same time, select an appropriate Media
Server for the location of the requesting subscriber. The Network Server also performs a
central role in supporting Clearspan redundancy capabilities.
Provisioning new subscribers can occur via synchronization of the group and user data
between Application Servers and Network Servers. The Network Server functions with
the Application Server as shown in the following figure:
Network Devices
Subscriber S
Location I
P
S
I Translations
P & Routing
Figure 20 Network Server
The policy database provides public and private (that is, enterprise) policies, to manage a
system provider’s network services. It also maintains subscriber location information to
track where subscribers are hosted within the network. The policy database contains
translation processing and a routing engine that is driven by a flexible policy approach.
Dialing plans, call typing, route selection, and network services configuration are policy-
driven and can be updated “on-the-fly”, including the introduction of new policies within the
network. Operators can configure the precedence of their routing policies to match
requirements.
The ServiceOS manages the sessions, which are the network connections associated
with a user or network element.
6.1.3 Media Server
The Media Server functions together with an Application Server (AS) and enables
enhanced services, such as Auto Attendants, Video Auto Attendants, Meet-Me,
Conferencing, Multimedia Messaging, video advertisements in Call Center queues, play
tones and treatments to callers. The Media Server supports these services for wireline,
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42. wireless, and/or converged networks, offering enterprises enhance productivity for end-
users. Media Servers can be geographically distributed, which can minimize call latency
and bandwidth utilization.
AS HTTP
S S RTP
I I RTCP
P P
NS
Figure 21 Media Server
In a stand-alone architecture, SIP and HTTP are used as standard protocols for
communication between the Application Server, Network Server, and the Media Servers.
The Application Server requests resources from Media Servers and controls the behavior
of those resources. Third-party media servers can also be deployed and controlled via a
standard SIP interface.
Enterprise providers can choose from multiple codecs that are supported on the Media
Servers. Configurable classes of multimedia service can also be assigned to enterprise
providers, groups, and individual users, restricting callers to the Codecs in their assigned
set. Enterprise providers can opt for lower bit-rate Codecs to increase the number of
simultaneous calls that can be provided on an access link to end users. G.729 is one of
the available Codecs supported.
In addition, the Clearspan system can be configured to route calls differently depending on
the Codecs they use, eliminating network elements that do not support included media, or
prioritizing network elements that offer better support for included media.
6.1.4 Web Server
System providers deploy Web Server farms to support Clearspan system web interfaces
and additional external interfaces. The Web Server supports the CommPilot Interface
using HTTP, and the Open Client Interface. System providers can choose to use either of
these interfaces or both concurrently. The following figure shows the functions within the
Web Server:
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43. Web Portals,
End Users and
Applications
Administrators
and Plug Ins
O H
C T
I T
P
O L
Data C O Subscriber
Access I C Location
•
Figure 22 Web Server
6.1.4.1 Open Client Interface
The Open Client Interface (OCI) is an open interface that enables third-party applications
to leverage Clearspan call control and provisioning functionality. This interface operates
using both XML and HTTP/SOAP. Thus, Clearspan makes it easy for developers to
create new applications to augment existing Clearspan functionality. For example, the
OCI queries the Network Server to find the Application Server with the requested data
such as a user’s mobile number or department.
6.1.5 Conference Server
The Conferencing Server is a specialized media resource that provides a complete set of
enhanced business conferencing features, including web-based presentation and
collaboration. A single pool of Conference Servers can support multiple Application
Servers in a Clearspan system. The Conferencing Server functions as shown in the
following figure:
Access and Network
Devices
R
T
P
S H
Resource T Data
I T
Control P Retrieval
P
•
Figure 23 Conference Server
The Conferencing Server is fully integrated with the Clearspan back office and operates
on standard hardware, thereby allowing for cost-effective scaling with the rest of the
platform.
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