Internet Protocol (IP) telephony and IP-based video conferencing solutions present
many opportunities to your organization, and at the same time introduce an
entirely new set of challenges to overcome. IP telephony benefits your organization
by providing simplified administration, toll bypass, and a unified messaging
platform. All of these benefits have the potential to save your organization a great
deal both administratively and monetarily when implemented correctly.
Several new IP telephony-specific enhancements need to be made to your
infrastructure in order to make IP telephony a reality.The CallManager system
replaces the traditional Private Branch Exchange (PBX) system for call processing;
currently in release 3.1, it has the potential to support up to 2500 IP telephones
per server and 10,000 per cluster. IP telephone handsets provide the user
interface to the IP telephony infrastructure. Currently in their second-generation,
Cisco offers four IP telephone handsets: the 7910/7910+SW, 7940, 7960, and
7935. Gateways provide the interface to the public switched telephone network
(PSTN). Cisco products currently support three protocols: the Skinny Station
Protocol (SSP), H.323, and Media Gateway Control Protocol (MGCP).The
Cisco Unity product suite offers a unified messaging solution, integrating voice,
video and fax communication into one medium.
IP telephony applications are used to enhance the IP telephony product
offering. Cisco has developed several IP telephony applications to work within
the AVVID product offering.WebAttendant is a software-based attendant console
used to replace the traditional PBX attendant console. It provides call monitoring
and management functions and can be used to monitor up to 26 conversations
concurrently. IP SoftPhone is a software-based version of an IP telephone, providing
a viable alternative for traveling users or others who do not have access to
an IP telephone. Internet Communications Software (ICS) is a grouping of five
tools: Automatic Call Distribution (ACD), Cisco IP Contact Center (IPCC),
Intelligent Contact Management (ICM), the Customer Interaction Suite, and
Network Applications Manager (NAM), for service and application providers.
Interactive voice response (IVR) and AutoAttendant are used for menu-based
telephone systems. Other vendors have also developed applications to work with
Cisco’s IP telephony solutions, which includes Interactive Intelligence, Latitude,
and Intelligent Telemanagement Solutions (ISI). Interactive Intelligence offers the
Interaction Center platform, installed on the ICS 7750. Latitude offers the
MeetingPlace IP software for video-conferencing, and ISI offers an accounting
and billing application that utilizes the call detail record (CDR) of each call.
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New World Technologies • Chapter 2 61
Video over IP (VoIP) is made possible through the use of several devices
including gateways, gatekeepers, multi-point control units (MCU), video terminal
adapters (VTA), and endpoints. Gateways provide access to the outside world
from your internal network. Gatekeepers are used to permit or deny requests for
video conferences. MCUs serve as a center for video-conferencing communications
and infrastructure.The VTA’s role in video conferencing is to provide an
interface to legacy video-conferencing systems. Endpoints are the end-user
devices that subscribe to and receive services from video-conferencing. Cisco
offers the IPVC family of products to meet the video-conferencing needs of
organizations. Cisco also offers the IP/TV family of products for one-way video
broadcasting.
Additional infrastructure, including switches and routers, will also need to be
adapted in order to meet the needs of AVVID. Cisco’s voice-ready routers include
the 1750 Series, 2600 Series, 3600 Series, and 7200 Series. All of Cisco’s switches
support IP telephony, but the 3524XL-PWR, 4000 Series, and 6000 Series support
inline power. Inline power can come in the form of inline power modules
for the Catalyst switches or external power-patch panels.
Queuing and class of service (COS) measures must also be taken on your
LAN/WAN in order to ensure real-time delivery of voice and video traffic.
802.1Q provides a Layer 2 queuing solution for your LAN environment.
Solutions Fast Track
Introduction to IP Telephony
Simplified administration is achieved by converging three separate
networks into one, allowing one resource pool to administer the entire
network.
Toll bypass allows organizations to avoid costly telecommunications
expenses by utilizing the data infrastructure.
Unified messaging combines voice-mail, e-mail, and faxes into one easyto-
use interface.
IP Telephony Components
CallManager provides the IP telephony network with a software-based
PBX system.
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62 Chapter 2 • New World Technologies
IP telephones provide the user interface to the IP telephony network.
Gateways provide the interface between the IP telephony network and
the public switched telephone network (PSTN) or a legacy PBX device.
Exploring IP Telephony Applications
WebAttendant replaces the traditional PBX attendant console.
IP SoftPhone provides a software-based IP telephone handset.
Third-party applications include software from Interactive Intelligence,
Latitude, and ISI.
Introduction to Video
Traditional video-conferencing utilizes ISDN lines in a point-to-point
infrastructure.
IP-based video-conferencing utilizes the H.323 specification allowing
for video-conferencing over a variety of mediums.
IP-based video-conferencing is much more efficient than traditional
video-conferencing because the existing data infrastructure is utilized
opposed to a separate infrastructure.
Gateways provide access to the outside world from your internal
network.
Gatekeepers are used to permit or deny requests for video conferences.
Multi-point control units (MCU) serve as a center for videoconferencing
communications and infrastructure.
Enhancing Network Infrastructure
Routers provide gateway services and voice aggregation for IP telephony
by use of analog ports, FXO, FXS, E&M as well as digital trunking cards.
Routers that support IP telephony include the 1751, 2600 Series, 3600
Series, and 7200 Series.
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New World Technologies • Chapter 2 63
Switches that support inline power modules include the 3524XL-PWR,
6000 Series, and 4000 Series.
Inline power is also provided by using the Catalyst inline power patch
panel.
What Does the Future Hold ?
Future revisions on CallManager include a call center solution.
Pizza box and integrated access devices will provide all-in-one
functionality for branch offices.
IOS-based versions of CallManager will further develop.