Overview of Voice over IP (VoIP) Support at UCSB

Original posting 8/6/03, reposted 2/25/04

Purpose of This Document

This document was developed by some 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. Appendices provide links to supporting documents and information on trials and developments at other higher education institutions.

Overall Summary

For those who don’t want to read through the entire document, here’s a brief overview:

• No known production VoIP networks are installed on the UCSB campus.
• Communications Services has no plans to offer VoIP as a production service at this time.
• Communications Services is just beginning to evaluate the use of VoIP as a replacement for the digital “key” (multi-line) telephone systems currently used in over 200 locations on campus.
• If a campus department installs a VoIP network, Communications Services can provide connections between the department’s VoIP network and the campus telephone switch.
• Due to current budget and time restrictions, Communications Services is not able to commit any staff time to assist departments with their VoIP research, installation, operation, or maintenance at this time. We hope to provide this assistance at some time in the future, but probably not during fiscal year 2003/04.

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).

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 in a paper from Compass Consulting titled Understanding Voice Over IP.

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:

1. A well designed data network. Some design considerations are presented below, in the section "Potential VoIP Liabilities."
2. IP telephone instruments (see below).
3. 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.
4. A VoIP gateway that 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:

1. IP telephone sets. These are replacements for the common analog telephone instrument that probably sits on your desk today. These telephone sets work only in a VoIP network and cannot be used on the Public Switched Telephone Network. In most cases, IP telephone sets are proprietary (at least for all but a minimal set of functions) and are not intended to be used on a VoIP network that mixes equipment from more than one vendor. While many IP telephone sets use an industry standard for voice digitization (H.323), the signaling and control standards (e.g., H.225) are not uniformly implemented by manufacturers, so very little functionality beyond connecting two sets to talk with each other is supported when mixing IP telephone sets in the same network.
2. 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.
3. Analog phones with adapters. Several VoIP systems support connecting your existing analog telephone set into their VoIP network using an adapter.

Potential VoIP Benefits

1. 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.
2. 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.
3. 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.
4. 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).
5. Potential of accessing the campus VoIP network from off campus (e.g., home) and your office phone can be extended to your home. 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).
6. 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

1. 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. 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.
2. 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.
3. 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), very few, if any, VoIP systems provide similar accommodations.
4. 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 network. Experiences by other universities implementing VoIP indicate that implementing QoS in your data network is mandatory. Not using QoS will lead to "pops and crackles" on the line, missing speech periods and, possibly, dropped calls. If you’re designing a VoIP network 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 will 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.
5. 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.
6. 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 have traditionally supported data networks and staff that have 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.
7. Network upgrades potential. Unless you are moving into a new campus building, or are having your space renovated and are installing a new data network, you may have to make substantial upgrades or replacements to your existing data network equipment to support electrical power over Ethernet, Quality of Service, and VLANs.
8. VoIP server reliability and security. VoIP networks 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. If you implement a VoIP network, you should consider how well that network 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 failures. If you plan to use a VoIP network for voice communications, you should consider keeping a few cellular telephones in key locations in case you have a long-term power or network failure.

What are UCSB and Communications Services Doing Regarding VoIP?

While there may be some research being done at UCSB on VoIP networks and equipment, there are no known installations of production-level VoIP networks on campus.

Communications Services is just beginning to evaluate the use of VoIP in two areas:

1. As a replacement for a digital "key" telephone system that serves a single department in a single campus building.
2. As a replacement for a digital "key" telephone system that serves one or more departments in more that one campus building.

A digital "key" system is one that supports multiple digital telephone sets, each with one or more telephone line, and is connected to the campus telephone switch via analog lines. An example of this type of system is the Panasonic DBS. Panasonic is discontinuing this line of equipment, so we are evaluating whether to look for another digital "key" system, or to recommend using VoIP systems to provide the same (and probably more) functionality. This evaluation may not be complete until the summer of 2004.

A third area, using VoIP to bypass the centralized campus telephone system and provide voice communications between on-campus and off-campus groups of people, all using VoIP instruments, is not yet under consideration by Communications Services.

A review of pilot programs at several other universities (see Appendix A), leads Communications Services staff to believe that some of the VoIP vendor offerings are very good, but that none of the systems are mature enough to replace the conventional telephone service currently used campus-wide. We plan to continue monitoring the development of this technology, and will install a small demonstration system, only if the University's and the department’s budgets warrant this expense. Given the current condition of the budgets, this seems unlikely during fiscal year 2003/04.

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 any staff time for assisting departments with their VoIP research, installation, operation, or maintenance at this time.

Connection of Departmental VoIP Networks to the Campus Telephone System

Communications Services is currently not implementing VoIP networks on the UCSB campus as a production service. However, we can provide connections between a department’s VoIP network and the campus telephone switch in one of two ways:

1. 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. Visit our website for information on obtaining telephone service.
2. 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 network." Your request will be routed to the appropriate staff members for circuit design and installation.

Appendix A - Links to Additional Documents

Several universities are conducting or have completed trials of VoIP networks. A couple have committed to campus-wide implementation. Below is a list of some of these universities and links to information on their programs.

Brigham Young University: Converted entire campus telephone system to VoIP. Their web site does not appear to have any information on their migration to VoIP, but does offer information on using the IP Phone system.

Carnegie Mellon University: Trial completed and a final report (pdf) is available.

Concordia University (Quebec, Canada) : Replaced their entire Centrex system with a Cisco AVVID system over the summer of 2003. Information on their Voice-over IP Project includes an overview, FAQ, and reference materials.

Florida International University (34,000 students, 1,100 faculty, 5,000 stations): Launched its plan to install a campus-wide IP Telephony system in 2000.

Indiana Higher Education Telecommunication System IP Telephony Task Force Report (pdf, June 3, 2003).

Penn State University: Plans to convert entire campus (40,000 lines) to VoIP by 2007.

Stanford University: Pilot phase of their Voice over IP Project completed. Expected a "go/no-go" decision in May 2003, but none listed on their website.

Other Documents

Colleges Experiment With Routing Phone Calls Over the Internet (The Chronicle of Higher Education, Nov. 16, 2001)

VoIP Security (ComputerWorld)

VOIP Hot, but Users Sweat (ComputerWorld)

EDUCAUSE Net@EDU Integrated Communications Strategies

Internet 2 VoIP Working Group

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