Download 1 - City of San Carlos

Presents to the
Telecommunications Technology
Review and Assessment
October 2005
CITY OF SAN CARLOS
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Telecommunications Evaluation 2005
Page
TABLE OF CONTENTS
I. Introduction
3
II. Executive Summary
3
III. Objectives
3
IV. Evaluation Methodology
4
V. Current Telephone System Environment
4
VI. Call Accounting System
5
VII. Voice Processing System
5
VIII. Cabling
6
IX. IT and Voice Infrastructure
6
X. Traffic Analysis
6
XI. Overall Voice System Evaluation
6
XII. City of San Carlos Telephone User Needs Analysis Meetings
8
XIII. General Trends in PBX Technology
5
XIV. Telephone System Design Alternatives
10
XV. Local Trunking Issues
18
XVI. Summary and Conclusion
19
XVII. Requirements of New System Basic Design Configurations
20
XVIII. Recommendation
22
APPENDIX I Power over Ethernet (PoE) Whitepaper
23

Present Telephone System Environment Schematic Drawing
Exhibit A

City Wide Design – Option 1.) Schematic Drawing
Exhibit B

City Wide Design – Option 2.) Schematic Drawing
Exhibit C

City Wide Design – Option 3.) Schematic Drawing
Exhibit D

Telephone System Options Cash Flow Analysis
Exhibit E
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I. Introduction
The following report outlines the results of World Communications Group’s analysis of the
strategic and economic telephone system upgrade alternatives available to the City of San
Carlos.
Also detailed is a description and evaluation of the current telephone service and related
ancillary systems currently in service at the City.
II. Executive Summary
The City of San Carlos is currently supported by a re-furbished telephone system that was
purchased in 1987, upgraded in 1992. It is approximately three (3) generations removed from
today’s state of the art technology. The system is, and will continue to be, costly to
maintain. Replacements parts have become scarce, which can seriously jeopardize the ability
for the City to adequately service the calling public.
Council directed at their May 9, 2005 that an action plan was to proceed that would replace the
City's current telephone system and to present alternatives and detailed recommendations to
improve communications capacity and capability, and enhance system flexibility. In this regard,
the City has engaged World Communications Group to conduct a detailed study and evaluation.
Consultant has performed the necessary tasks, which we believe will provide the information
and guidance to accomplish the goals and objectives set forth by Council. Essentially, we have
examined the current telephone and IT environment at each primary City facility, and
interviewed a representative number of employees from all City Departments. In addition, we
engaged in many personal meetings and telephone conferences with our existing
telephone service providers, IT manufacturers and other vendors to gather research and
information for this analysis.
During our interviews with City staff, if became clear that there is a strong belief that the present
system lacks the features necessary for today's work environment, and excellence of support
by the current phone vendor. Very little happens in business or local government today that is
not preceded or following by a telephone conversation. Therefore, is has become commonly
recognized how important an easy-to-use and cost efficient telephone system is to the
successful conduct of business in today’s fast-paced world. Consequently, getting the user
community’s input early on in our evaluation proved to be extremely useful.
Equally important is an organization’s ability to manage and maintain its telecommunications
resources in-house. This generally allows for significant costs savings over outside vendorsupported services. The present City telephone system network does not currently provide that
opportunity. Modern telephone systems, albeit a bit more technologically complex, inherently
provide the tools to self-administer and maintain both telephone system hardware and software
functionality. The result, in the long run, is lower cost of ownership.
We have also reviewed the City's current telephone network architecture and costs, as well as a
substantial sample of the miscellaneous monthly telephone billings. It is our belief that there are
opportunities to reengineer the existing basic telephone trunking arrangements and reduce
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costs. It is our finding that the City's Emergency Operation Center must be addressed outside
of the City's phone system to ensure that this system is available during a crisis situation.
(please expand here).
In our review it was determined that two locations needed handling outside of the project as
well, due to their proximity, and their existing systems. Fire Station 16 was reviewed and found
to be an adequate phone service, and will not be included within the project. Laureola Park
was determined to be a location that needed special consideration. We are recommending that
the old 1A2 type telephones be replaced with a new Electronic Telephone Key System due to
the lack of connectivity to the city hall. However, both locations will continue to have telephone
extension (and DID capability) from the new proposed City Hall phone system
In terms of overall the telephone system, based on our findings, we have outlined, in this report,
three (3) alternative telephone system upgrade designs. Five-year projected costs have also
been detailed for each of these choices.
Option 1. Traditional TDM Telephone Network - A traditional TDM (Time-DivisionMultiplexing) PBX can be described as a state-of-the-art digital switching system, which has
been the front-running telephone system technology since the mid 1970’s. They have, over
the years, become feature rich and are able to interface with Information Technology
databases through a technique called Computer Telephony Integration. They support both
analog and digital telephones, although the latter are usually proprietary to a particular
vendor platform, (CTI). These systems have a long track record of very stable service with
extremely reliable uptime. Configurations can economically scale and support, from about
30 to over, 40 thousand telephones.
Option 2. Converged TDM/IP (also referred to as IP Hybrid) - This design is typically
based on a LAN-connected call server supporting IP telephones and traditional circuitswitched (digital) port carrier equipment distributed across a LAN/WAN infrastructure. This
requires a voice-ready packet-switched enterprise IT network. The converged design is
optimal for organizations with distributed communications requirements across a campus
environment and a balanced mix of TDM (analog, digital) and IP stations. However, if could
be configured as all TDM or all IP, with the flexibility to mix-and-match as conditions dictate.
Option 3. Client Server (also referred to as VOIP) - The Client Server PBX model is a
100% packet-switched design absent any circuit switching (digital) capability. Media
Gateways are utilized to support trunks and analog telephones. This arrangement also
requires a voice-ready packet-switched enterprise IT network and is optimal for
organizations who plan to install a significant percentage of IP telephones and have limited
analog station port requirements.
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We have prepared an RFP driven by the City Staff's Business Requirements, which allows
freedom to the vendor community to design and propose their "best practice" phone
solution for our City.
It is also recommended that the following items also be pursued during the project:

First and foremost we would strongly suggest consolidating all local and long distance
telephone services under the SBC/CalNet program.

A Phone Service Audit be completed to determine if all phone number that are being
billed are in service and/or could be replaced by utilizing the new proposed telephone
system.

The EOC Phones be replaced as a separate project, concurrent with the new Phone
system installation. By providing phone service directly from the local exchange carrier,
independent of the new phone system, reliable uptime capability is assured in the event
of a commercial power or main phone system failure.

A Project Manager is hired for the implementation of the phone system with duties
including the insurance of the phone number portability as well as overall re-engineering
of the voice trunking network from our current service provider to the new service
provider.
III. Objectives
The Objectives of the study was to find solutions which will enable the City to:
a. Automate and improve voice communication capability,
b. Increase productivity in communication tasks,
c. Automate routine tasks,
d. Reduce operating costs,
e. Provide superior customer service to other departments and to the public,
f. Provide the ability to access a wide range of voice communication services and
technological advances as they become available.
g. Meet with staff to determine existing shortcomings and/or perceived needs
h. Consider probable telecommunications requirements for continuing service over the
next 7 - 10 years
i. Examine alternative system(s) designs;
j. Recommend preferred system designs.
IV. Evaluation Methodology
The following methodology was used in conducting this evaluation:
a. Several personal discussions and telephone conversations, and miscellaneous emails
with members of City Information Technology management: Ms. Connie Dillard,
Information Technology Manager and Mr. Todd Rovatti, Systems Analyst.
b. Group meetings with City managers and staff of various City departments,
c. A review of the City’ available telecommunications records and inventory.
d. Telephone, FAX and email exchanges with miscellaneous City telephone service
providers: Mr. Albert Gonzales, Senior Account Manager, SBC; Mr. Bill Wilde President, Mr. Roosevelt Matthews- Operations Manager, Creative Interconnect; Mr. Jim
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Chase- Account Manager, Mr. Darin Kelly- Systems Engineer and Mr. Maz Zabaneh
Territory Account Manager, Cisco Systems; Mitel Consultant Liaison Support Group as
well as several miscellaneous telecom system vendors.
e. A review of SBC Telephone billings and related records.
f. Personal tours of all City facilities.
g. A review of available Centigram/Mitel Networks (Voice Processing) technical data.
V. Current Telephone System Environment
The following telephone system network is currently providing all of the City’s voice
communication services:
1. Main PBX-City Hall
The telephone system currently in service at the City Main facility, 600 Elm Street, is a 2-cabinet
Mitel Networks upgraded Mitel 200SX-Digital PBX system supported by Mitel 15 generic
software. The system is configured as follows:
Number of Cards
Item
Ports Equipped
Working
Spare
4
15
18
2
5
2
CO Trunk
Digital Line
Analog Line
ONS (analog line)
DID/Tie
T-1
16
180
144
24
10
48
16
178
Unknown
12
10
48
0
2
Unknown
0
0
0
This system supports the following City facilitates via direct cable connectivity:
 Senior Center: 601 Chestnut Street
 Library: 610 Elm Street
 South County Fire Station 13, 525 Laurel Street
Telephone Instruments
There is a mix of approximately 180 digital telephones, and 150 analog port devices
powered by the City Hall PBX. A RightFax fax server supports faxing to the desktop. There
are no empty card slots available for expansion in this single Processor Cabinet /Port
Cabinet arrangement
2. Remote Offices
Telephone service to several remote locations is supported from the main PBX via Creative
Interconnect leased T-1 connections. These T-1’s are arranged to support both voice and data
to the remote locations. The specific telephone equipment at each remote site is as follows:
Location
Telephone Equipment
Youth Center : 1001 Chestnut
Mitel Networks SX200 ML (Lightware rel 17) PBX System
Burton Park: 1017 Cedar Street
This system supports both the Youth Center and the Burton
Park Kiwanas building (connected via direct cable).
It is
configured for 24 digital and 12 analog station ports and the T1 to the Mitel PBX at City Hall.
Corporation Yard: 1000 Bransten
CITY OF SAN CARLOS
Mitel Networks SX200 ML (Lightware rel 16) PBX System
This system provides telephone service to all Corporation Yard
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buildings and consists of 36 digital and 12 analog station
ports, 6 CO analog trunk ports and the T-1 card which
connects to City Hall
Fire Station 16, 1280 Alameda De Las Pulgas
Connected to City Hall PBX via SBC leased lines terminated
on an Iwatsu Omega Key Telephone System.
Laureola Park, 525 Old County Road
Connected to City Hall PBX via SBC leased lines terminated
on 1A2 key telephone instruments.
VI. Call Accounting System
The only Call accounting functionality is provided via Automatic Identification of Outward Dialing
(AIOD) through the current network reseller Teltrex Management Corporation, dba Creative
Interconnect Telemanagement of San Carlos California. This only provides outgoing call detail
at the individual station level via Creative Interconnect monthly service billings. It does not
support any in-house capability to produce detailed usage reports or traffic analysis.
VII. Voice Processing System
The current Voice Processing System supporting all City employees is a Mitel Networks, Mitel
Mail Model 70 Release (6) with 18 Loop Start Ports and 55 hours of voice storage. One port is
used for message waiting lights, and another provides outbound access for notification to
pagers. The current telephone system vendor, Creative Interconnect, has advised that they are
in the process of upgrading this system to release (7) software, but that the port count will be
reduced to an unknown quantity.
VIII. Cabling
CAT5 wiring runs to all data and phone locations at most City locations, usually in a
complement of 2 RJ45 and 2 RJ11 jack arrangements. Although there are no detailed cable
records available, this should not be an issue or have any significant affect on the deployment
of a new telephone system
IX. IT and Voice Infrastructure
1. The City IT Infrastructure includes 9 sites.
2. The main site, City Hall, has pure Cisco Network equipment including Dual redundant Core
6505’s, 4006, and 3524XL switches. All of this equipment is connected via multi-mode fiber
(MMF) running at 1GB. VLANS have been created for data and phone.
3. The Library is connected to the City hall with MMF and 100 pair copper, and has a 3524 XL
Switch.
4. The Adult Community Center and Fire Station 13 are connected with single-mode fiber
(SMF) and 100 pair copper, with similar switching gear.
5. The Corporation Yard carries phone over a T-1 Connection, and Data over an 802.11b
wireless connection.
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6. The Laureola Park Building has off-premise extension (OPX) lines for phone and a wireless
connection for data.
7. The Youth Center and Burton Park Buildings are connected by a T-1 for voice and wireless
for data.
8. Fire Station 16 only has OPX lines for phone.
9. The City Network and application standards are pure Microsoft. We have a mix of Microsoft
Windows Server 2000, and 2003. Our desktops are a mixture of Microsoft Windows 2000 and
XP. The City currently run Exchange 2000 for email services, and a RightFax server for fax
services.
X. Traffic Analysis
1. The current Mitel telephone system network does not provide traffic statistics; therefore, we
are unable to ascertain an exact grade of service on the voice network. No major complaints
were expressed during our discussions with City employees that would suggest any problem
with dialing station to station, receiving incoming calls from the public network, or placing
external calls.
2. Similarly, the IT network is not currently monitored for throughput analysis, so statistics for
data traffic cannot be determined at this time.
XI. Overall Voice System Evaluation
1. Telephone Switching System Network
Creative Interconnect, the company who continues to service and maintain the equipment,
apparently originally installed the current Mitel PBX telephone system in 1992. At that time the
system was reconditioned and was limited to only analog telephone support. The PBX was
upgraded in 1994 to provide for digital telephone capability.
The original Mitel SuperSwitch PBX was introduced in the early 1980’s and utilized analog
“space-division” computer switching technology. The 200SX Digital version is a hardware and
software upgrade that allows the system to support digital as well as analog telephone
instruments. This retrofit of the original model became a very popular upgrade for Mitel in the
early 1990’s. It is important to note that the current release of this product is now at Version 15.
While it is possible to upgrade the existing system to a higher version of software release, we
do not believe that it would be economically sound to do so. This system has served the City
fairly well for a significant period if time, however by most industry standards it is well past the
projected useful of life of this vintage of telephone switching systems.
2. Voice Processing System
We do not believe that any further upgrades to this system would be justified. Also the storage
capacity is rather limited. Today’s technology for voice storage is virtually unlimited and is, in
many cases, based on the size of the system’s standard hard disk storage capacity. A 40 Gb,
for example, would provide 8,000 to 10,000 hours of storage.
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XII. CITY OF SAN CARLOS Telephone User Needs Analysis Meetings
1. Following are the results of the citywide telephone user surveys conducted via group
meetings and email replies. Participants from City departments were:
NAME
DEPARTMENT
NAME
DEPARTMENT
Jennifer Moore
Recreation
Vicky Galea
Recreation
Janet Leus
Recreation
Tonya Booker
Recreation
Barry Weiss
Recreation
Kathy Giraud
Recreation
Anita Olsen
HR/Recreation
Andrea Greenberg
HR
Sherry Henderson
HR
Janet Beaugh
HR
Justin Anderson
IT
Jasmine Frost
IT
Jeff Maltbie
City Manager
Nekaya Nachmann
City Manager
Christine Boland
City Clerk
Darcie Connell
Reception
Carroll Woods
Building
Chris Valley
Building
Dorothy Dale
Public Works
Don Gilbert
Public Works
Paul Baker
Public Works
Laura Snideman
Economic Dev.
Laurie Cudworth
Planning
Liz Cullinan
Planning
Stephanie Bertollo-Davis
Planning
Kristina Woemer
Planning
Serena Nevarez
Planning
Mary Arnold
Police
Sandra Spagnoli
Police
Jenna McAlpin
Police
John Murphy
Police
Doug Eckles
Police
Marti Overton
Police
Donna Raffaelli
Police
Linda Navarro
Finance
Diane Stow
Finance
Beth Liu
Finance
Sandy Johnson
Finance
Mary Nakamura
Finance
Richard Averett
Finance
Rebecca Mendenhall
Finance
Marilyn Maytum
Finance
With respect to the perceived quality of telephone and voice processing service provided by the
existing telecommunications network, a pattern of complaints or issues were expressed by a
fair amount of the general population who participated in this study.
Here are the City staff Business Requirements voiced during these meetings.
Many of the features listed below are available within the current system as marked by *
 Ability to forward call to cell phones, pagers,
 More detailed “out of office” messaging
 More than three-way conference calling
 *Cordless headsets for hands-free conversations
 Call waiting and caller incoming I.D. on all phones
 Unblock caller ID on outbound calls
 Two or more greeting options - one standard and one for holidays, vacations, time
away, etc.
 Direct lines for incoming calls (by employee name, department)
 “Mute” feature for conference calls
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 *Program speed dial from desk
 *One-touch voice mail access
 More buttons on phone for access to features and to see who is on the phone
 *Dial out without lifting receiver (hot dial pad)
 *Call pickup groups
 Intercom through speakers on phone
 Different rings for internal and external calls
 Ability for incoming callers to dial out of voicemail to another extension at any time
 Incoming meet-me-conference capability
 Wireless phones for mobility
 Choice of different number of rings before going to voicemail
 Slow down (or speed up) voicemail messages
 Better Speakerphone
 Recording of phone calls
 Consistent types of phones throughout the City departments
 More extensions on phone
 Multiple voicemail boxes per person/extension
 Customized marketing messages played while on-hold
 Ability to answer your phone from other phones, outside your department

Specific requests of Police Department





Voicemail notification via cell phone
Recording of all business calls
Ability to dial back to outdoor telephones
Expand Police overhead paging system
Ability for polices officers (without phones) to be notified of voicemail messages on a
monitor panel
Specific requests of IT Department Administration and Management














Cordless Phones that work throughout city hall.
Network Monitoring Tool for voice, data. With full reporting features.
Maintenance/Parts Contract with 2 to 4 hour on-site parts replacement.
Interactive Voice Response Capable
Integrated Messaging with Exchange/Outlook, allowing voice messages to stay on the
Voicemail Server and are handled as pointers into the Exchange Server.
Keep current city hall phone numbers 650-802-4XXX
Trunk and T-1 monitoring and alarms
In-House Administration and support; Training for all IT Staff on Moves, Adds, Changes,
System Administration, Reporting.
Call Accounting Package with full reporting features
Parts Inventory Management
Network, Hardware and IP Schema Assessment with Maintenance Plan and 5 year
budget
Auto Attendant for after-hours and before hours
Client Software must be Microsoft W2K, XP and Vista Compliant
Exchange 2000 + Compliant
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


Administrator’s ability to set up Global VM Distribution Lists
At least music on hold, if not in-house marketing messages
Full Documentation of the new hardware, wiring, system setup, trunks and phone
numbers
Today’s basic telephone switching systems (PBX’s) provide standard capabilities and
additional features that would correct or otherwise satisfy nearly all of the comments or
requests for enhancements discussed above. Any of these applications could be easily
introduced into a new PBX platform based on the individual needs of each department or
section. The basic designs of contemporary telephone systems all conform to
international telephony standards to support these potential enhancements. The
requested functionality that are advanced optional features can be incorporated in the
Request for Proposal documents as additional items.
XIII. General Trends in PBX Technology
(Excerpted from The City of Sunnyvale “Telecommunications Policy” 2000/2001.
“ … Rapid development of advanced telecommunications resources
carries the promise of new economic prosperity, new tools for streamlining
the delivery of both public and private services, and new opportunities to
improve the quality of life of citizens. While cities can anticipate these
benefits in the near future, local governments must be mindful of the
impact of this emerging industry on them and on the citizens they serve.”
In keeping with the foregoing observation, it is important to note that the global PBX industry is
in the throes of revolutionary change. Driven by advances in technology and changing
customer needs, its vendors have to find new direction – most commonly toward the realm
traditionally inhabited by computer vendors. PBX vendors’ evolution will have to more closely
mimic that of the computer world in order to compete, including heightened attention to service
and support, the unbundling of architectures, intensive software development, and greater
involvement in activities such as systems integration and IP Telephony.
IP Telephony has already begun changing the face of the PBX industry. With more demand for
integration between the computer and the telephone, telephony platforms are rapidly expanding
into the data side of networks. The intelligence and processing power is clearly moving out of
the PBX and towards a more distributed architecture based on PC’s and on-line servers.
Although it is certain that, at this point, the PBX is better at real-time call processing than the
data side, it is only a matter of time before the data world gains the experience and expertise
needed to catch up. Some may say that they already have. This combined with the fact that the
data folks are much better at bandwidth management and networking, means that the computer
industry is posing a real threat to the PBX industry. However, the data side will first have to
deal with the issue of reliability that PBX vendors have effectively addressed for many years
through, among other things, redundancy.
The bottom line, though, is that forward-thinking business and governmental enterprises should
be prepared to view PBX systems in place today as a last generation platform. The transition
from PBX to IP Telephony is not likely to evolve at a uniform pace; instead, we will see a
gradual collaboration of PBX and data processing/IS vendors. PBX functionality will no longer
be proprietary, but instead will be transformed into telephony-featured software, operating on
industry-standard, computer based, and network platforms.
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The core architecture platform of PBX systems is undergoing an important transition from
circuit-switched to packet-switched transmission and coding techniques. Time-division
multiplexing (TDM), using Pulse Code Modulation (PCM), has been the primary digital
transmission method used by PBX systems for the past quarter century, but the future of voice
communications appears headed towards incorporation of the Internet Protocol (IP). During the
past 3-5 years, almost every major PBX manufacturer has introduced platforms that incorporate
IP into its system design, and for two primary functions: To support peripheral ports (desktop
stations and/or trunk circuits) and for signaling/transmission links between distributed port
equipment cabinets.
Internet Telephony, along with technologies like Asynchronous Transfer Mode (ATM), MPLS,
video and audio compression and super-powered computers, will lead us to incredible
advances in communication products. We will see high-quality video conferencing that will be
affordable enough to be in everyone’s home. We will see a global communication network that
will far surpass today’s telephone network
Every day, the gap that exists between Internet Telephony and traditional communication routes
grows smaller and smaller, internet gateway servers now provide a foundation for technologies
to come. Manufacturers will continue toward the goal of unifying Internet Telephony with the
traditional public phone system. Internet Telephony may not entirely replace the existing
system, but will enhance it with better products, better features, better reliability and better
performance, which gives real power to everyone.
It is paramount that the City evaluate telecommunications system vendors who can not only
provide today’s up-to-date technology, but who have already economically migrated into the
inevitable world of IP technologies.
XIV. Telephone System Design Alternatives
Since the onset of this project, it has been our primary intention to remain mindful of the City’s
concern for the overall level of service provided by its telecommunications facilities for both its
staff and the citizens of San Carlos. In that effort, we have attempted to seek solutions, which
could minimize the overall cost of attaining that goal.
During the course of our review and interviews, several important observations were made.
Specifically, that while there exists a small number of the City’s administrative staff that are
satisfied with what they have, there are a substantial number who are either relegated to the
use of out-dated “plain old telephone system” hardware or must live with less than full-featured
voice-mail capability—or both.
In truth, there can be inexpensive, stopgap measures, which might be recommended and
implemented to alleviate some of these situations. But in light of the seriousness of the more
obvious technological and end of lifecycle shortcomings of the current Mitel PBX network and
ancillary hardware as outlined earlier in this report, our professional judgment has taken us on a
different course.
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Accordingly, World Communications Group offers to the City three (3) upgrade options to
consider:
Option 1. Traditional TDM Telephone Network Here we envision a single “master” PBX
system at the Main Campus, 600 Elm Street (City Hall, Library, and Senior Center) which
controls two (2) remote survivable nodes at:
Site 2. The Corporation Yard
Site 3. Burton Park / Youth Center
1000 Bransten Rd
1017 Cedar St./1001 Chestnut St.
This design will ensure the uniformity and support of digital telephones, voicemail and call
accounting at all three PBX locations and the remote sites that they support. Connectivity to the
main site would be accomplished via leased T-1 circuits with either conventional or IP
technology. The following locations would be served as remote OPX sites utilizing analog
extensions on single line or electronic key system telephones in much the same way as they
are now.
Site 4. Laureola Park
Site 5. Fire Station 16
525 Old County Rd
1280 Alameda De Las Pulgas
Site 6, Fire Station 13, could be supported with either existing direct copper cable or fiber
connections to digital phones or as a remote survivable node (in much the same way as Sites 2
& 3) incorporating T-1, conventional or IP connectivity with either copper, fiber, or leased line.
Option 1 would provide the significant flexibility for system management and administration,
since all sites are controlled from the main campus switch and voicemail system through a
single database. Additionally all, or most, of the existing voice cabling infrastructure can be
reused, as is. Backup trunks at each remote site could allow for placing emergency calls, in the
unlikely event of a total T-1 outage. Connectivity back to the main switch to allow for station-tostation calls and voicemail access is also optionally possible during T-1 circuit failure through
dialup trunks back to the main site. See Exhibit B
Pros
Cons
Least expensive to install
May not initially support IP Telephony
Simply to engineer and design
Diminished Vendor R&D policies
Shortest Interval to deployment
Requires CTI development for database access
Largest compliment of standard features
Digital telephones are vendor specific (proprietary)
Proven reliability of technology
Could utilize nearly all existing station wiring, as is
Modifications to IT infrastructure not required
Easy to Administer and Maintain
Unlikely to require additional administrative and
management staff
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Estimated Purchase costs including, installation; sales taxes; general user, system
administration and Attendant Console training; one-year full warranty and:

o
o
o
o
o


All PBX hardware, software and telephone instruments:
250 digital stations equipped
48 analog station ports
Redundancy of call processing
2-PRI’s and 12 analog trunks for local access
2-T-1 for connectivity to remote survivable nodes
Voicemail w/Integrated Messaging (200 users)
Call Accounting and System Administration tools
$185,000
25,000
15,000
Total $ 220,000
Since no IP Telephony is involved in this design, there would be no need to modify the existing
IP infrastructure and all existing voice cabling would be reused, as is. Total expected costs for
this alternative is $220,000.
Option 2. Converged TDM/IP Often also referred to as IP Hybrid technology, these systems
are generally based on a LAN-connected call server supporting both IP and/or traditional circuit
switched (digital) endpoints (telephones) distributed over a LAN/WAN infrastructure and/or
existing copper cabling. Analog station ports are supported via peripheral equipment modules
or Media Gateways
Here again, we envision a single “master” PBX system at the Main Campus, 600 Elm Street
(City Hall, Library and Senior Center) which controls two (2) (or 3) remote survivable nodes at:
Site 2. The Corporation Yard
Site 3. Burton Park / Youth Center
1000 Bransten Rd
1017 Cedar St./1001 Chestnut St.
These nodes could be configured to support any combination of digital and IP or analog
telephones. This design will allow for and support the mix and match of digital telephones and
IP telephones, voicemail and call accounting at all three PBX sites. Connectivity to the main site
would be accomplished via leased T-1 circuits with either conventional or IP technology.
However, where IP telephones are deployed, the City’s IT infrastructure must be verified for
Quality of Service (QoS) on all appropriate data switches and routers, as well as Power over
Ethernet (PoE) capability for each IP telephone instrument. Our investigation has revealed that
the current model of IT switches employed at all City locations (Cisco Systems 3524XL) are
specifically designed to support PoE for the majority of Cisco only IP telephones. This
arrangement does not comply with the universally accepted PoE standard 802.3af.
Consequently, we believe that the City must consider other methods of adhering to this
standard. A fairly economical method of accomplishing this would be to retrofit the distributioncabling infrastructure with power options. See Appendix I – Power Over Ethernet Options.
Additionally, those parts of the City’s IT infrastructure supported via (Ethernet standard 802.11)
wireless technology would likely require complete reengineering and re-design in order to
support IP telephony. This type of wireless infrastructure is not recommended for phone
systems due to latency and Quality of Service (QoS) issues. Here, digital technology could be
deployed at locations currently connected to the City’s wireless IP infrastructure.
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Whenever, and wherever digital phones would be deployed the existing voice cabling system
could be reused, such as in the case of Site 6, Fire Station 13. Site 4, Laureola Park, and Site
5, Fire Station 16 would be served as remote OPX sites utilizing analog extensions on single
line or electronic key system telephones in much the same way as they are now.
Site 4. Laureola Park
525 Old County Rd
Site 5. Fire Station 16
1280 Alameda De Las Pulgas
Site 6. Fire Station 13
525 Laurel
In this configuration Site 6.could be supported via, either, existing direct copper cable or fiber
optic connections to digital phones as a remote survivable node (in much the same way as
Sites 2 & 3) incorporating T-1, conventional or IP connectivity with either copper, fiber, or
leased line. Or, if IP phones are the choice for this location, as an extension of the City’s WAN
infrastructure. See Exhibit C
With this alternative, it is important to note that the look and feel of all telephones instruments
would be universally designed and configured. This would ensure complete transparent to each
user whether they are using digital or IP technology.
Pros
Cons
Provide maximum flexibility of design
Mixed inventory of IP and digital telesets
Fairly easy to engineer and design
IP Readiness Survey recommended
Short Interval to deployment
Requires CTI development for database access
Large compliment of standard features
Digital telephones are vendor specific (proprietary)
Reliability and experience of Legacy vendors
Could utilize a fair portion of existing station
wiring
Modifications to IT infrastructure could be
minimized
Costs of Moves/Adds greatly minimized
Unlikely to require additional administrative and
management staff
Estimated Purchase costs including, installation; sales taxes; general user, system
administration and Attendant Console training; one-year full warranty and :

o
o
o
o
o


All PBX hardware, software and telephone instruments:
A combination of 250 digital and IP stations equipped
48 analog station ports
Redundancy and/or failover of call processing functionality
2-PRI’s and 12 analog trunks for local access
Possible 2- T-1’s for connectivity to remote survivable nodes
Voicemail w/Integrated Messaging (200 users)
Call Accounting and System Administration tools
$200,000
25,000
15,000
Total $ 240,000 +
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Costs for upgrading the current IT network to provide and/or ensuring Quality of Service (QoS)
and Power over Ethernet (PoE) at those locations where IP phones are desired will vary based
on final design. Our best estimates would be approximately $12,000.00 to conduct an IP
readiness survey and approximately $15,000.00 to retrofit the cabling/switching infrastructure to
support PoE. Total Estimated costs for this option are: $267,000.
Option 3. Client Server, Voice over Internet Protocol (VOIP) is a peer-to-peer packetswitched design, absent of circuit switched (TDM bus) common equipment. Media gateways are
deployed to support non-IP endpoints i.e. analog devices and trunks to the Public Switched
Telephone Network (PSTN) This design requires a 100% QoS and PoE capable IT
infrastructure to enable real-time voice communications.
Here again, we envision a single “master” LAN based PBX system at the Main Campus, 600
Elm Street (City Hall, Library and Senior Center) which controls two (2) remote survivable
nodes at:
Site 2. The Corporation Yard
Site 3. Burton Park / Youth Center
1000 Bransten Rd
1017 Cedar St./1001 Chestnut St.
Connectivity to the main site would be accomplished via leased T-1 circuits utilizing a separate
(voice only) or shared (IT and voice) WAN IP technology. Since all telephones are IP only, the
City’s IT infrastructure must be modified to support Quality of Service (QoS) on all appropriate
data switches and routers, as well as Power over Ethernet (PoE) capability for each IP
telephone instrument. The exiting IT infrastructure, albeit very robust in many ways, is not
currently capable of supporting this arrangement without the required power support inclusion.
Our investigation has revealed that the current model of IT switches employed at all City
locations (Cisco Systems 3524XL) are specifically designed to support PoE for the majority of
Cisco only IP telephones. This arrangement does not comply with the universally accepted PoE
standard 802.3af. Consequently, we believe that the City must consider other methods of
adhering to this standard. A fairly economical method of accomplishing this would be to retrofit
the distribution-cabling infrastructure with power options. See Appendix I – Power Over
Ethernet Options.
Additionally, those parts of the City’s IT infrastructure supported via (Ethernet standard 802.11)
wireless technology would likely require complete reengineering and re-design in order to
support IP telephony. As an alternative, a separate IT LAN infrastructure could be built to
specifically support the IP Telephony requirements. Because wireless technology is currently
deployed at these locations (Sites 2 & 3) for IT support, the separate LAN/WAN arrangement
might a better choice for this design.
The following locations would be served as remote OPX sites utilizing analog extensions on
single line or electronic key system telephones in much the same way as they are now.
Site 4. Laureola Park
525 Old County Rd
Site 5. Fire Station 16
1280 Alameda De Las Pulgas
Site 6. Fire Station 13
525 Laurel
In this configuration Site 6.could be supported via an extension of the City Hall LAN using
existing fiber optic cable connectivity or as a remote survivable node (in much the same way as
Sites 2 & 3) incorporating T-1, IP WAN technology. See Exhibit D
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Pros
Cons
Provides for a single network platform
IP Readiness survey recommended
Lesser cost of connectivity to remote sites
May require significant modifications to IP Network
Largely based on accepted TCP/IP standards
Slightly higher deployment and maintenance costs
Costs of Moves/Adds greatly minimized
Requires precise engineering and design
Adequate compliment of standard features
More extensive training required of IT staff
Can easily connect remotely via WWW access
May require augmentation to IT staff
Projected future extensive development of IP
Telephony applications
Will require third-party voicemail for “Integrated
Messaging”
Service outages affect both voice and IT functions
A myriad of Security issues
Estimated Purchase costs including, installation; sales taxes; general user, system
administration and Attendant Console training; one-year full warranty and:



All Call Processing hardware, software and telephone instruments:
$ 215,000
o 250 IP stations equipped
o 48 analog station ports
o Redundancy and/or failover of call processing functionality
o 2-PRI’s and 12 analog trunks for local access
o Possible 2- T-1’s for IP networking to remote survivable nodes
3-rd Party Voicemail w/Integrated Messaging (200 users)
25,000
Call Accounting and System Admin
15,000
Total $ 255,000 +
Since all telephones in this configuration would be strictly IP, costs for upgrading the current IT
network to provide and/or ensure Quality of Service (QoS) and Power over Ethernet (PoE are
estimated at: approximately $15,000.00 to conduct an IP readiness survey and approximately
$20,000.00 to retrofit the cabling/switching infrastructure to support PoE. Re-engineering and/or
replacements of the current wireless IT infrastructure is projected at $20,000.00: Total
estimated costs for this option are: $310,000.00
With all of these alternatives, Options 1, 2 & 3, all features on all telephones, as well as all voicemail,
call accounting and other ancillary applications are transparent to all users.
With either of these designs, we strongly recommend that, at least, the main site PBX call processing
functions be fully redundant to provide for maximum reliability.
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XV. Local Trunking Issues
At present, the City is utilizing both SBC and Creative Interconnect to provide local dial tone for
all incoming and outgoing telephone traffic. Some miscellaneous incoming PBX trunks as well
as a myriad of business lines are being provided by SBC through the State of California CalNet
contract. This is a very good program that allows tax-supported agencies to receive less-thanmarket rates for local and long distance telephone service. However, the majority of telephone
lines connected to the City Hall PBX system are being provided by the current network
Competitive Local Exchange Carrier (CLEC) Teltrex Management Corporation, dba Creative
Interconnect Telemanagement of San Carlos California. The present majority of PBX trunking
consists of T-1 connectivity and supports both local and long distance outbound calling as well
as inbound calling to Direct In Dialing (DID) telephone number ranges 650-8002-4100 to 4499
and 650-486-7600 to 7699. We do not believe that the latter group is being used.
It is our recommendation that the new proposed telephone system trunking be re-engineered
for ISDN/PRI technology, consolidated and transitioned to SBC for all dialtone services. Utilizing
the benefits of reduced rates and consolidated billing though CalNet will realize many benefits.
Additionally, PRI will bring to the City the much desired and requested incoming Caller ID
functionality.
Current monthly charges from Creative Interconnect for all services relating to the PBX network
averages approximately $5,850. Here is the detail of those charges:
1. Monthly service agreement for maintenance: $2,285
2. Monthly T-1, DID and local trunking costs: $1,015
3. Miscellaneous circuits and POTS lines $ 484
4. Monthly local and long distance usage charges: $2,066
Item 1., maintenance charges for the new proposed telephone system would not be applicable
during the first year of service and should be reduced (depending on the chosen Option) to
approximately $1300 to $1833 beginning in year 2.
In terms of the local trunking and usage costs, in our Opinion, re-engineering the voice network,
porting all of the telephone numbers and transferring the usage service to SBC/CalNet should
reduce these costs by a minimum of 25%, or approximately $517. See Exhibit E for Cash
Flow Analysis
We have also conducted a cursory review of SBC/CalNet miscellaneous telephone billings,
which are running approximately $ 4,000 per month. In order to determine the validity of these
services and the potential of any additional savings, a thorough audit of all of the telephone
numbers currently being billed should be undertaken.
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XVI. Summary and Conclusion
Based upon the foregoing, it is the opinion of World Communications Group that the existing
telephone and voicemail systems are providing only a minimum level of telephone service to
City employees and the calling public. We believe that there are many efficiencies and
opportunities to improve public and employee communications and satisfaction by replacing the
existing PBX network. City certainly faces many of the challenges that leading organizations
face today. This includes the need to do more—faster; to meet increasing community needs; to
make higher quality decisions in shorter time frames; and to contain constantly rising costs.
Consequently, we are recommending that the City strongly consider soliciting proposals from
leading telephones system providers to replace the entire PBX and voicemail platforms
currently in service. Costs for a complete new telephone system and network, for all existing
City offices, will vary somewhat depending on which of the listed options are chosen. Lease
purchase plans could spread these costs over 5 to 7 years.
Here is a summary of the 3 Alternative designs which were outlined above:
Option 1. Traditional TDM Telephone Network
Based on several decades of experience, it can be said that this option would likely be the least
costly and easiest to implement and manage. Digital telephone switching technology has been
around since the mid 1970’s with hundreds of thousand of these systems still in service. Digital
Telephone systems continue to be the choice of many organizations that find that this
technology more than adequately fills their needs and objectives. However, many, if not all, of
the major legacy telephone system manufacturers rarely ship and install these systems without
the capability of being IP enabled. Circuit switched systems are capable of interfacing to IT/ IP
networks; integrate with customer databases and generally support integration to MS Windows
based ancillary voice applications. Many telephony applications, such as Voicemail with
Integrated or Unified Messaging, Call Accounting systems, System Administration Inventory
and traffic Management systems are often MS Windows based. Contact Center applications
such as ACD, Workforce Management, Interactive Voice Response (IVR), will also be often
connected to the LAN for desktop managed functions. You will find this technology supporting
well over 500-600 standard features. Although the system would be interfaced to the City’s
LAN/WAN infrastructure, the current voice cabling distribution system would, for the most part
remain, as is.
Option 2. Converged TDM/IP (Hybrid)
This scenario would offer a significant amount of flexibility. It can support, both circuit switched
and IP switching capability. It will accommodate the mix and match of digital, IP and analog
telephones and can be designed and configured in any number of ways depending on the most
sensible and cost effective connectivity and networking efficiency. This design architecture can,
of course, be totally configured for IP, or totally configured for digital. Since these systems are
the result of the legacy telephone system manufacturer’s engineering and design, fully featured
generic software functionality packages have been carried over from traditional and very
reliable TDM platforms. All of the capabilities for interfacing and integrating with IT/IP and
database applications described in Option 1., would apply to this offering as well. Costs for this
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alternative will vary somewhat depending on how much IP Telephony is utilized, requiring
modifications to the existing IP Infrastructure.
Option 3. Client Server (VOIP)
This alternative takes the giant leap into an all IP Telephony world. Because of the availability of
today’s new convergence technology more and more organizations are planning to deploy voice
traffic over existing data networks. With the Internet explosion and advanced PC applications
that use more and more bandwidth, the data network volume has increased dramatically and is
now the dominant bandwidth consumer. Although, for many years it has been possible to carve
up bandwidth to accommodate both voice and data over a single network, different
technologies still had to be deployed. However, it now appears to make sense to use the data
network to transmit voice instead of the voice network to transmit data. It is often wise;
however, to perform an IP telephony /VoIP network audit for each LAN/WAN segment prior to
introducing IP Telephony traffic. Network engineering must provide for a worst-case scenario
when deploying voice on an IP network.
This technology appears to be gaining more and more steam, but many new lessons are being
learned. Some common issues that need to be carefully addressed are:








Power for IP Telephones (802.3af Power over Ethernet-PoE) See Appendix I
Quality of Service (QoE) Network equipment must be capable of prioritizing voice traffic.
Security issues that were nonexistent in circuit-switched systems
Call processing redundancy and failover functionality between nodes to insure
availability, reliability and maximum uptime
Disaster recovery plan of action
More in-house training requirements and the possibility of additions of support staff
Substantial increase in UPS requirements
Increase in commercial power requirements in cabling closets
If these and other issues are considered and prepared for, this technology can surely provide a
very high level of telephone service to its users. We expect that this solution will be a bit more
costly to implement and maintain, depending on the level of reliability engineered into the
overall design.
XVII. Requirements of New System Basic Design Configurations
Each of the suggested scenarios will provide a very efficient and uniform telephone system
structure for all of the staff of the City. The basic design should include the following features,
applications and functionality:





Telephone system and call processing/integrated messaging requirements to support
growth for a minimum of 400 users
Redundancy Requirements
Uniformity in the look and feel of all telephone instruments
(display/speakerphone/headset options, etc)
Higher end telephones for Senior Management, City Officials and power users
Voicemail with Unified/Integrated Messaging options
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









Paging and hands-free intercom through telephone instruments
Unlimited voicemail distribution lists
Automated Attendant
Conditional voicemail greetings (busy, don’t-answer, vacation, etc.)
Call accounting, with account codes
Caller ID
5-6 party Conference
Retain existing DID numbering plan
Standard feature packages will include these and a myriad of up to an additional 500
standard, system, station and attendant console features.
Music-on-hold (requires ancillary third-party music or announcement equipment)
Optional requirements not included in budget estimates may include:




Wireless adjunct (Cordless telephone capability)
o In order to cover the entire City Hall campus environment alone, we estimate that
this would require a minimum of 30 indoor and outdoor wireless access points.
Cost estimates could exceed $50,000- $60,000 for this option
Cordless headsets – Available directly from headset manufacturers and telephone
supply outlets.
Contact Center (ACD, IVR) functionality
o Specific applications and design would need to be clearly identified in order to
obtain pricing for this option
Recording of telephone and voicemail conversations
o In order to record all incoming trunks, costs for this option could also exceed
$50,000 depending on logging and retrial capabilities.
Administrative and management features and tools




Telephone and Voicemail System administration for adds, moves and changes.
Traffic monitoring
Trunk monitoring with alarm notification
Inventory and cable management systems
o
Costs for this application will vary considerably and is not included in our budgetary cost
estimates

Network management and monitoring system
o Costs for this application will vary considerably and is not included in our budgetary cost

Advanced technical training
o Requirements will vary considerably depending on final system architecture and design
estimates
Other optional features, which might be required or desired, that may come to light, can be
included in the RFP documents as we continue along in this process.
XVIII. Recommendation
After carefully reviewing and analyzing all of the data gathered during this study, World
Communications Group is recommending Option 2. Converged TDM/IP, as the most viable
choice of providing new telephone system services for the City. While a pure Client Server
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design would provide many benefits, it will not allow the flexibility that we believe the City needs
based on the current environment and budget. With the Converged TDM option, highly reliable
and proven TDM circuit switched technology can be readily positioned at several City locations
that otherwise would require the necessity of augmenting and/or modifying the exiting IT
Infrastructure. On the other hand, IP endpoints (telephones) could be deployed wherever and
whenever it would be economically sound to do so. Consequently, with this alternative, the City
can take advantage of demonstrated, time-tested digital technology and still have the ability to
strategically and systematically migrate to the inevitable world of IP Telephony and VoIP.
We trust that this information will allow the City to develop a telecommunications upgrade
strategy that will provide a very high quality of telephone service to both its citizens and
employees. Obviously, any major changes in equipment, software or procedures require careful
planning, implementation, user training and ongoing management.
Finally, it is important to acknowledge the professional assistance and cooperation of Ms.
Connie Dillard and her staff throughout course of this phase of the project. We sincerely
appreciate their efforts and support on our behalf.
World Communications Group will continue to be available to further assist the City in
developing the City’s long-term telecommunications strategies and ultimately carrying out its
goals and objectives.
Respectfully submitted
Peter G. Bologna
WORLD COMMUNICATIONS GROUP
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APPENDIX I -- Power Over Ethernet
White Paper – 5/2004
Introduction and Motivation
Power over Ethernet (PoE) is a revolutionary technology that extends the already ultra-broad functionality
of Ethernet by supplying reliable DC power over the same Category 5/5e twisted-pair cable that currently
carries Ethernet data. PoE, modeled after the technology used by the telecommunications industry to
supply reliable power to telephones, enables lifeline quality power for IP telephones (VoIP) as well as
many other low power Ethernet network devices like wireless access points (WAP) and security cameras
as shown in Figure 1.
PoE, or IEEE standard reference 802.3af, began the standardization process in 1999 to address the need
to ensure interoperability among a growing number of proprietary methods of distributing DC power to
network devices. Now that the standard has been passed, the ubiquitous Ethernet RJ-45 plug and outlet
make up the first universal worldwide power connectors. Consequently, PoE equipment vendors are
designing standards-based products that leverage the numerous advantages offered by PoE. These
products include security access systems, battery chargers, vending and gaming machines, electric
guitars and even electronic shavers. Constantly emerging applications using PoE are limited only by the
ingenuity of the product designers.
Figure 1. Typical PoE installation utilizing a powered
patch panel midspan PSE to support common low
power Ethernet devices.
Network equipment investments are expected to
provide functionality that support current and future
productivity enhancements. Deploying a PoE network
today offers the following advantages that will also
support tomorrow’s innovations.
• Lower cost. PoE eliminates the need for
running both data and power wires to each
network device. WAPs and security cameras
can be installed without the additional expense
of contracting an electrician to install AC outlets where deployed. PoE also helps protect IT
investments as it is forward and backward compatible with other Ethernet protocols. Furthermore,
PoE devices that are Simple Network Management Protocol (SNMP) manageable can be
remotely monitored and controlled to efficiently manage or troubleshoot power consumption
and/or failures.
• More flexible. Network devices can be installed and re-located where performance is optimum
and not tethered to an existing AC outlet. This is especially important for devices like WAPs,
which may be installed in hard to reach places like the ceiling in order to achieve the broadest
coverage.
• More reliable. A SNMP manageable centralized power source enhances the protection against
power overloads, outages, surges and spikes. When PoE is implemented, along with
uninterruptible power supplies (UPSs) or battery backups, it allows enterprises to distribute power
even when the AC electrical power is down. This enables them to replace conventional
telephones with feature rich VoIP phones while retaining the lifeline reliability benefits.
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Due to all of these advantages, it is not hard to understand why PoE is generating so much interest and
excitement among IT vendors and consumers.
How PoE Works
There are two basic components in a IEEE 802.3af compliant PoE network: a device that supplies power,
known as the Power Sourcing Equipment (PSE) and a device that receives and utilizes the power, known
as the Powered Device (PD). Upon connection of any network device to a PSE, the PSE must first
determine or “discover” if the device is a PD or not. This ensures that existing Ethernet equipment, that
may not be PoE compliant, is not forwarded power and possibly damaged. The PSE does this by applying
two small current-limited voltage signals across the cable and checks for the presence of a characteristic
resistance; power is provided only if this specified resistance is detected. As an optional extension to the
discovery process, a PD may also classify how much power it will require from the PSE. This feature
supports the PSE by helping it supply power in an efficient way.
After the PSE has discovered a PD, it will supply 48 V and a maximum current of 350 mA. Accounting for
the voltage drop due to the cable losses, a minimum of about 13 W is available to the PD. This is enough
power for numerous applications including VoIP telephones, WAPs, security cameras and building access
systems. IEEE 802.3af is not targeted to support desktop computers, servers or printers. Once the PSE
begins to provide power, it continuously monitors the PD current draw. Once the PD current consumption
drops below a minimum value, for example when the device is unplugged, the PSE discontinues supplying
power and the discovery process begins again.
The standard defines two different types of PSEs: endspan and midspan. An endspan PSE integrates the
power sourcing functionality with a network switch. Endspans available today look and function exactly the
same as any other Ethernet switch, except they can provide PoE in addition to routing data. Since
Ethernet data pairs use transformers coupled at each end of the link, DC power can easily be added to the
center tap of the transformer without disrupting the data. In this mode of operation, an endspan injects
both power and data on pin-pairs 3 and 6 and pin-pairs 1 and 2.
A midspan PSE fits in between the switch and the PD. It supplies power over the unused cable pin-pairs 4
and 5 and pin-pairs 7 and 8; data is routed through the midspan device without modification as shown in
Figure 2. These devices are usually mounted adjacent to the Ethernet switch in an equipment rack. It is
important to note that although the PSE must use the pin-pairs assigned to an endspan or midspan, not
both, the PD must have the capability to accept power from both an endspan or a midspan.
Figure 2. A midspan PSE supplies power on the unused wire pairs
and is typically a stand-alone device.
Midspan devices offer the advantage of retaining the current
investment in a switch that does not support PoE. Furthermore, since
midspans are less expensive than endspans, midspans are the more
cost-effective way of adding PoE on a port by port basis to an
existing network. A single midspan may be used to support multiple
switches with connections to PDs that require PoE.
Currently, there are two different types of midspan devices: a power
hub and a powered patch panel. A power hub has two RJ-45 outlets
for each PoE port, an input and output, both of which are located on the front. A patch cord connects the
switch port to the input of the hub and an additional patch cord connects the matching hub output to a
patch panel and subsequently the PD. The other type of midspan, a powered patch panel, combines the
functionality of a midspan device with a conventional patch panel. By using a powered patch panel
midspan, such as the PANDUIT® DPoE™ Power Patch Panel, the switch connects directly to the PD
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through the panel. A RJ-45 patch cord connects the switch to the front of the patch panel while the PD is
connected to the back of the panel on the matching punchdown terminal. Power is added to the unused
data pin-pairs within the patch panel. Using this simplified approach requires fewer ports, fewer patch
cords and less rack space compared to power hub midspans as shown in Figure 3.
Figure 3. Comparison of implementation configurations for the two types of midspan PSEs: powered patch
panel (left) verses power hub.
Conclusion
PoE is a rapidly emerging technology that is enabling the efficient deployment of reliable VoIP and
wireless networking tools to increase the efficiency of communication across the enterprise. Furthermore,
since PoE has significant cost savings, flexibility and reliability advantages over traditional AC power, it
reduces the overall cost of network ownership. Although both endspan and midspan devices deliver PoE,
the PANDUIT® DPoE™ Power Patch Panel midspan PSE offers the most efficient solution to upgrade the
network with PoE enabled applications.
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