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Overview of Voice over IP (VoIP) Support at UCSB |
January 2010
Purpose of This Document
This document was developed by staff of Communications Services to provide the UCSB campus community with a brief introduction to Voice over IP (VoIP) technology, list some of the potential uses of VoIP at UCSB, and present some of the technology's potential benefits and liabilities. Communications Services' recommendations regarding the implementation of VoIP and what the department will do in support of this technology are presented.
Overall Summary
For those who don't want to read through the entire document, here's a brief overview:
- There are a few VoIP systems installed on the UCSB campus. These systems were installed by staff within the departments using them and are not being used to provide VoIP services to other departments. The departments known to have installed VoIP systems are Chemistry, Kavli Institute for Theoretical Physics, and Physics. None of these departments are using VoIP systems for all of their telephone services; all continue to have some traditional telephones connected to the campus's centralized telephone system.
- Some departments may be able to reduce their monthly telephone expenses by installing and operating a VoIP system. We have a model VoIP ROI Spreadsheet (xls) that can be used to estimate if a department might reduce their expenses by installing a VoIP system.
- Communications Services has no plans to offer VoIP as a campus-wide production service to replace the campus's centralized telephone system at this time.
- Communications Services is evaluating the use of VoIP as a replacement for the digital "key" (multi-line) telephone systems currently used in over 140 locations on campus and to provide centralized telephone system services to some off-campus locations.
- If a campus department installs a VoIP system, Communications Services can provide connections ("trunking") between the department's VoIP system and the campus telephone switch which will enable faculty and staff to retain their telephone numbers. This also eliminates the need for departments to manage toll-dialing number plans and perform recharge billing of call costs.
- Due to current budget and time restrictions, Communications Services is not able to commit staff time for assisting departments with their VoIP research, installation, operation, or maintenance.
What is VoIP?
With the availability of large bandwidth campus and departmental networks, many people are talking about deploying voice traffic over data networks for a variety of reasons. The basic idea is to use existing data networks to carry voice telephone calls to potentially reduce wiring cost or staffing levels, and provide additional functionality. This deployment is sometimes referred to as IP Telephony, and/or Voice over IP.
For the purposes of this document, these two terms need clarification:
- IP telephony (Internet Protocol telephony) is a general term for the technologies that use the Internet Protocol's packet-switched connections to exchange voice, fax, and other forms of information that traditionally have been carried over the dedicated circuit-switched connections of the Public Switched Telephone Network (PSTN).
- Voice over IP (VoIP) is a term used in IP telephony for a set of facilities for managing the delivery of voice information using the Internet Protocol (IP). VoIP is implemented in various ways using both proprietary (or vendor specific) and open protocols and standards.
IP telephony is a term for a generic type of service, while VoIP is a term for a specific application of IP telephony, carrying telephone voice traffic over a data network using IP. Additional introductory information on VoIP is available on the Internet. Open your preferred web browser and search for "understanding voice over IP" or "understanding VOIP."
When and How Can VoIP Be Used?
In an ideal installation, VoIP can eliminate the need for two cable plants, one for data network connectivity and
one for voice communications (see subsequent section on Potential Benefits). It may be possible to eliminate the need for a centralized telephone switch for some, or all, telephone calls.
The most common uses of VoIP are:
- To interconnect VoIP phones within a single building using the building's Local Area Network (LAN).
- To interconnect VoIP phones between multiple campus buildings using the campus backbone network.
- To interconnect VoIP phones in different organizations (e.g., UCSB and another university) using the commercial Internet and/or private Wide Area Networks (WANs).
This document addresses only the first two types of use.
What Is Needed to Make VoIP Work?
The minimal components needed to implement a VoIP configuration are:
- A well designed data network. Some design considerations are presented below, in the section "Potential VoIP Liabilities."
- IP telephone instruments. See below.
- A call management system. Call management delivers the functions usually provided by a telephone system, such as call setup, call routing, placing a call on hold, etc. The call management functions are provided by software running on a data network server.
- A VoIP gateway then connects the VoIP system to either the Public Switched Telephone Network or the campus telephone switch to provide connections with non-VoIP telephone customers. This gateway can be a stand-alone device, or the functions can be provided by a telephone switch that is "IP enabled."
IP telephone instruments fall into one of three general categories:
- IP telephone instruments (also called "hard phones"). These are replacements for the common analog telephone instrument that probably sits on your desk today. These telephone sets work only in a VoIP system and cannot be used on the Public Switched Telephone Network or connected directly with the campus telephone switch. There are proprietary (vendor specific) and open standards based instruments. The open standards based telephones are commonly referred to as SIP (Session Initiation Protocol) phones, and are available from a variety of manufacturers. Some SIP telephones are proprietary (at least for all but a minimal set of functions) and are not intended to be used on a VoIP system that mixes equipment from more than one vendor. However, interoperability of different vendors� SIP phone features and functions is improving. You should carefully and thoroughly test a couple of SIP phones from different vendors to ensure they meet your needs before making a final selection.
- IP soft phones. These are personal computers with microphones, speakers, and a software application that enables the computer to function like an IP telephone set, while continuing to provide typical personal computer functions. There are numerous IP soft phone clients. Like IP telephone instruments, there are both open standards based clients, and proprietary implementations.
- Analog phones with adapters. Several VoIP systems support connecting your existing analog telephone set into their VoIP system using an adapter (called an ATA, or Analog Telephone Adapter).
Potential VoIP Benefits
- Possible savings in intrabuilding wiring costs for new buildings or renovations due to reduced wire infrastructure. Typically, campus buildings have two or three cable systems, one each for data networking, telephone connections, and cable television distribution. It may be possible to consolidate the data networking and telephone connection cable plants if VoIP is implemented, saving the cost of the second cable plant installation and maintenance. It should be noted, however, that in many, particularly newer, buildings, the "lateral" wiring that connects wiring closets to workstations is already the same for data connections and telephone connections.
- Low cost or free toll calls to some locations (e.g., other VoIP installations). It is possible to bypass the centralized campus telephone system and provide voice communications between on-campus and off-campus groups of people, all using VoIP instruments and the Internet. However, taking advantage of this potential savings requires more configuration and support for the Call Management system due to the need for careful dialing plan management and routing considerations.
- Can relocate instrument without central administrative support. Currently, moving a telephone line from one building location to another requires having a technician (either from Communications Services, an off-campus vendor, or your own department's staff) visit your office, find or install a new pair of wires to the new instrument location, change some wire jumpers in one or more wiring closets, and then test the changes. With a VoIP network, the instrument can be connected into any data network outlet and it should work within a matter of minutes. Just unplug it, move it, and plug it back in. There may, however, be network device management issues such as address assignment, firewall configuration, and port availability that must be resolved, typically by departmental network staff.
- Can "roam" between instruments and "log in" at any handy instrument, and it takes on the configuration of your office instrument. Some VoIP systems allow people to walk up to a telephone instrument in any office and dial a couple of numbers on the keypad ("log in"), and that telephone temporarily assumes the configuration of the telephone line in your home office (e.g., it assumes your telephone number, your list of speed dial numbers, and your intercom settings).
- Potential of accessing the campus VoIP network from off campus, and your office phone can be extended to your home or another remote location. It is possible to obtain a network service from a local Internet Service Provider (ISP), such as Verizon or Cox Communications, and connect a VoIP telephone set in your home to the VoIP network in your office. The telephone set in your home then has all of the features and capabilities of your office telephone set (but, consider the University's policies regarding the use of University facilities for personal business).
- Can acquire or develop applications that integrate voice and data applications. Some examples are unified messaging, pop-up database lookups based on incoming Caller ID, and web browsing using the telephone set.
Potential VoIP Liabilities
- Need for centralized power and power back-up for telephone sets. All VoIP telephone sets (including analog phones connected via a VoIP adapter) require electrical power to operate. Some VoIP telephone sets can get their electrical power from the Ethernet cable that connects the set to the VoIP network (using POE, or Power Over Ethernet). Others have a power cord that needs to be plugged into a wall electrical outlet. If electrical power to the telephone set fails, you won't be able to place or receive a call. So, you need to plan for electrical power backup.
Enhanced 911 can be difficult to manage, especially if people relocate instruments. All telephone sets connected to the campus telephone system can contact the Police Department's Dispatch Center and obtain emergency services by dialing 9-911. You don't even have to talk to the dispatcher to get assistance because the campus telephone system provides Enhanced 911 service with Automatic Location Identification (ALI). As soon as your call is answered at the Dispatch Center, a personal computer displays your telephone's physical location.
Using a VoIP network, with its benefit of being able to unplug a telephone set, move it, plug it in, and start using it, someone needs to know that the telephone set has been relocated, and get this information into the database that provides the Display Center with the ALI service. If you are using a VoIP telephone off campus connected to a VoIP network on campus, and that telephone number starts with 893-, you have to be very careful not to dial 9-911 on the off-campus telephone, because campus-based emergency assistance staff will be dispatched to your office location, which may or may not be in close proximity to the campus. Communications Services provides a web application to Update Service Locations, which allows departments to update the E-911 location data associated with campus 893 telephone numbers.
- Americans with Disabilities Act (ADA) compliance issues. The ADA and University policies require that departments provide their faculty and staff with reasonable accommodations, if needed. While many accommodations are available using traditional telephone systems (e.g., TDDs, large keypads, special headsets), the accommodations provided by VoIP systems are much more limited.
- Quality of Service issues. Quality of Service (QoS) is the set of techniques used to manage network resources in a manner that enables the network to differentiate and handle traffic based on policy. This means providing consistent, predictable data delivery to devices in your VoIP system. Experiences by other universities implementing VoIP indicate that implementing QoS in your data network is mandatory for ensuring consistent voice transmission quality. Not using QoS may lead to "pops and crackles" on the line, missing speech periods and, possibly, dropped calls. If you're designing a VoIP system to be used in a single building, on a single departmental LAN, QoS won't be critical. However, if you plan to interconnect VoIP sets in multiple buildings, using the campus backbone network for transport, QoS may become a major issue. In some cases, existing network hubs, switches, and/or routers may not support QoS and may need to be replaced with contemporary equipment.
- VLANs should be used. The use of Virtual Local Area Networks (VLANs) in an IP Telephony deployment is recommended. VLANs provide key functionality in two ways. First, by segmenting IP phones into their own VLAN, DOS (Denial Of Service) attacks can be eliminated. Second, VLANs are a great help in implementing QoS. By segmenting the IP phones into their own VLAN, excess traffic on a segment can be eliminated. Quality of Service (QoS) over VLANs configured on the UCSB backbone network has not yet been tested.
- Staffing issues. A VoIP implementation converges a data network and voice network into one network. Very few people who understand converged voice/data networks are available on campus. Problem isolation can be extremely time-consuming, especially if data networking and voice communications are supported by separate groups (or departments). In addition, staff that traditionally supported data networks and staff that supported voice network may have very different goals and experiences. Getting them to work together on problem resolution may require some extensive training and the acquisition of complex test equipment by each group.
- Network upgrades potential. Unless you are moving into a new campus building, or are having your space renovated and you are installing a new data network, you may have to make substantial upgrades to or replacements of your existing data network equipment to support electrical power over Ethernet, Quality of Service, and VLANs.
- VoIP server reliability and security. VoIP systems that are not dependent on a centralized telephone switch (e.g., IP-PBXs) use "off-the-shelf" data servers that run VoIP applications for call completion and feature support. VoIP servers are subject to hacking and viruses just like file servers and email servers, and require routine backups, maintenance, security checks, software upgrades, and electrical power backup. When was the last time you booted your file server compared to the last time you booted your telephone?
Most people expect their telephone to work every time they pick up the handset. Traditional telephone switches are built with a high degree of hardware redundancy to ensure a high level of fault-tolerance. Achieving the same level of hardware fault tolerance for VoIP servers introduces additional cost and complexity which must be considered.
If you implement a VoIP system, you should consider how well that system will provide service to administrative staff, many
of whom use the telephone for hours each working day, and what people will do
for telephone service during electrical power or server failures. If you plan to
use a VoIP system for voice communications, you should consider keeping a few
cellular, or standard hard-wired, telephones in key locations in case you have a
long-term power or network failure.
- VoIP and Voice Mail issues. Some VoIP systems have integrated voice mail capabilities. In many of these systems, the voice mail is converted to a digital file (e.g., a WAV file) and sent to a subscriber as an attachment to an electronic mail note. These notes can easily be forwarded to anyone other than the original recipient.
There is no prohibition in the University of California Electronic Communication Policy or any other UC policies against forwarding voice mail messages as an attachment, either within the voice mail system or outside the system. However, when a system that sends voice mail as electronic mail attachments is introduced, it would be helpful to inform the people that this new service is one used at other universities, along with a reminder that voice mail, like any other university record, should be handled in a manner consistent with UC policies.
In particular, point them to the UCSB Web page on Information Stewardship, and more specifically to Business and Finance Bulletin RMP-8 D. It is important to remind individuals who leave voice messages that they have no control over where messages may be forwarded.
What are UCSB and Communications Services Doing Regarding VoIP?
While there is research being done at UCSB on VoIP systems and equipment, there are only a few installations of departmental VoIP systems on campus. These departmental VoIP systems were installed and are operated and maintained by departmental staff, not by a campus-wide service provider like Communications Services.
Communications Services is evaluating the use of VoIP in some areas:
- As a replacement for a digital "key" telephone system (see below) that serves a single department in a single campus building or that serves one or more departments in more than one campus building.
- As a replacement for leased telephone circuits from local telephone companies between the campus and remote locations.
- As a replacement of standard analog telephone instruments and the campus centralized telephone system.
Digital Key System Replacement: A digital "key" system is one that supports multiple digital telephone instruments, each with one or more telephone lines, and is connected to the campus telephone switch via analog lines. An example of this type of system is the Panasonic DBS, which has been installed in about 140 campus departments. Because Panasonic has discontinued this line of equipment, we evaluated whether to look for another digital "key" system or recommend using VoIP systems to provide the same (and possibly more, possibly less) functionality. This evaluation is still underway and has, so far, resulted in the following.
- Some VoIP systems could provide most of the functionality of the Panasonic DBS systems but would not be exact replacements. People using a replacement VoIP system would have to learn how to perform some functions differently.
- Panasonic DBS equipment is still readily available from third-party distributers and the cost of Panasonic equipment from these vendors, in many cases, is less that the cost of designing, installing, and maintaining VoIP systems to replace the Panasonic equipment.
- While replacing a Panasonic DBS system with a VoIP system may work well for a single department in a single building, replacing a Panasonic system that serves more than one department and/or more than one building may require some considerable network upgrades.
- Additional testing, problem isolation, and maintenance procedures of this type of VoIP system are needed before it is offered to campus customers.
Service to Remote Locations: We are still evaluating the functionality and cost effectiveness of using VoIP systems to provide telephone services to some off-campus locations. These locations are currently using the centralized campus telephone system via leased telephone circuits from off-campus vendors and there may be cost savings by using a VoIP system, especially if the remote location already has a viable data network installed.
Campus PBX Replacement: The last area of evaluation, using VoIP to replace the centralized campus telephone system and provide voice communications between on-campus and off-campus groups of people, all using VoIP instruments, was also considered by Communications Services. Communications Services believes this is not a viable alternative, at this time, for the following reasons.
- The campus has invested several millions of dollars in the campus telephone system and this system has a remaining useful life of many years, at least five and perhaps many more beyond that.
- Adding a VoIP service would increase our expenses for equipment, software, and staff, without reducing any expenses, because we would have to continue to operate the existing telephone system unless every customer was moved to the VoIP system. Reducing the number of lines on the campus telephone system results in only a minimal reduction in expenses (for the telephone line interface card maintenance) because the campus purchased the system and does not lease it on a "cost per telephone line" basis.
- Moving every customer to a VoIP system would require an unknown expense to upgrade the existing Ethernet switches, routers, hubs, and electrical power systems in every building on campus that currently has standard telephone system connections. While this cost is unknown, it is expected that it could easily exceed one or more million dollars.
- Moving every customer to a VoIP system would require the replacement of most of the existing analog telephone instruments with VoIP instruments or interfacing the analog instruments with adapters which require power. Since the instruments are owned by the departments, this presents an interesting funding/ownership issue and an unknown cost.
A review of pilot programs at several other universities leads Communications Services staff to believe that some of the VoIP vendor offerings are very good, but none of the systems are mature enough and/or cost effective enough to replace the conventional telephone service currently used campus-wide at UCSB. At some time, the maintenance expenses of the existing centralized telephone system could exceed the cost of replacing that system with a VoIP system, but we believe that date is many years in the future. We plan to continue monitoring the development of this technology.
Connection of Departmental VoIP Systems to the Campus Telephone System
Communications Services is not currently implementing VoIP systems on the UCSB campus as a production service. However, if campus departments want to implement VoIP using their own resources, there are no known restrictions to prevent them from doing so. Communications Services will provide connections between the campus telephone switch and their VoIP gateways, using either analog or digital station lines, at then-current recharge rates. However, given the condition of our budget, previous commitments to supporting other campus projects, and a potential reduction in staffing levels, we are not able to commit staff time for assisting departments with their VoIP research, installation, operation, or maintenance at this time.
We can provide connections between a department�s VoIP system and the campus telephone switch in one of two ways:
- We can provide analog telephone lines between the campus telephone switch and a departmentally supported VoIP gateway. These lines are no different than any other telephone line we provide and can be obtained by using our standard procedure for requesting telephone service.
- We can provide digital telephone lines via a Primary Rate Interface (PRI) circuit between the campus telephone switch and a departmentally supported VoIP gateway. This is not yet a production service, but we
will work with you to provide this service. To have a PRI circuit installed, follow our standard procedure for obtaining telephone service and ensure that your request indicates that you want "a PRI circuit to a departmental VoIP system." Your request will be routed to the appropriate staff members for circuit design and installation.
A sample estimate for the installation of the second option (PRI circuits) is available for download: Sample VoIP Estimate (doc).
Finally, if you want to estimate whether your department would benefit financially by implementing a VoIP system, we have a model VoIP ROI Spreadsheet (xls) that can help estimate the life-cycle costs of a sample VoIP system compared to using the centralized campus telephone system.
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