Using VoIP to Improve NGOs Sustainability
Department of Information and Computer Sciences
University of Hawai’i at Manoa, Honolulu, USA
NGOs are often challenged by the high cost and lack of flexibility of ordinary telephone
systems. Often, there are many communication costs related to the management and
implementations of programs for NGOs. Due to the current global financial crises, these
costs become an additional burden on already heavy load of an NGO’s budget. Voice over
the Internet Protocol (VoIP) technology allows convergent systems, where web and voice
technologies use the same network to provide the necessary communication services, while
simultaneously eliminating unnecessary costs incurred from multiple phone lines, long
distance phone calls both international and national, and mobile phone usage. The
contribution of this paper is to show how NGOs could improve their productivity and cut
their financial costs by using a VoIP system. It discusses the requirements for installing VoIP,
the security issues related to using VoIP for an organization, and the quality of service of the
system itself. It includes a case study of MA’AN Development Center, a local NGO located
In recent years, networks have been embedded in almost everything in everyday life, from
placing a phone call or sending an email to running a business. What was initially a few
computers connected by some cables has now become a huge array of heterogeneous devices
connected by phone lines, optical cables, and satellites. The internet is becoming the
backbone of any business; employees and employers alike are relying on the internet.
Receiving or sending emails, conducting research or being connected to an intranet are such
examples; in today’s ever changing world, every successful business should have a
connection to the internet. Non-Governmental Organizations (NGOs) also rely on the
internet. NGO’s overall goal is to help communities and provide them with their most basic
needs without looking for a profit; therefore, most of these NGOs are also nonprofit
organizations. NGOs are distributed all over the world, and many of them cooperate and
work together to achieve similar goals. They communicate through the Internet, telephone,
and fax, as would any other business.
Traditional phone systems are expensive. Non-profit NGO’s sustainability is affected by the
efficiency of the systems they have. Replacing traditional phone systems at these NGOs with
Voice over Internet Protocol (VoIP) systems, the latest phone system technology, will help
NGOs to be more sustainable as they spend far less on communication costs. It converts
regular telephone calls into digital data delivering the voice communications over the Internet
or a packet-switched network. Essentially, when using a VoIP system, the Internet is used to
make telephone calls as opposed to a traditional phone line. How could NGOs benefit from
VoIP? Reducing the cost of calls and saving money for extended periods of time, having a
communication system that is more consistent and is the new trend for business and pleasure
alike, thus enhancing employees’ productivity. This all contributes to NGOs becoming more
sustainable and more efficient in the community they wish to serve.
2. Related work
VoIP or Internet telephone is real–time interactive audio over the internet. A user can make a
phone call from computer to computer, computer to telephone, computer to mobile, and vice
versa. Unlike traditional telephone services the call will be transmitted through the Internet
(Kurose and Ross, 2008).
2.1. What are VoIP requirements?
To get started with VoIP service, there are just three basic items that are needed: a computer,
Internet access, and free software. The process of transmitting voice over the Internet
involves numerous steps such as sampling the voice, compressing it, assembling it into IP
packets, and transporting them across a data network to the receiver. The receiver side
disassembles the packets, decompresses the signals, and audible signals are produced through
devices such as speakers (Walker and Hicks, 2004). This mechanism requires basic
components to be configured in order to enable its full functionality (Walker and Hicks,
2004). These components are categorized as follows:
A codec means either compressor - decompressor or coder - decoder, and can be
implemented in either hardware or software. The purpose of a codec is to encode a
data stream or signal from analog to digital and vice versa so that it can be sent out
over a networked interconnection. Essentially, there are a number of codecs available
with different characteristics such as speed and quality of the output (Practical
Asterisk 1.6 2009).
b) VoIP and TCP/IP protocols
Voice over Internet Protocols such as Real Time Protocol (RTP), and Session
Initiation Protocol (SIP) are used to transmit voice signals over the IP network. In the
TCP model these protocols work on the application layer, which has to interact with
the transport layer protocols such as User Datagram Protocol
(UDP) or Transmission Control Protocol (TCP) in order to be able
to transport data. For the purpose of providing telephony services,
there is a need that a number of different standards and protocols
c) IP telephony servers or private branch exchange (PBX)
An IP telephony server is usually a computer running a program that manages the
setup or connection of VoIP terminals, and determines the status of the destination.
Because the IP telephony server manages and controls all terminals, the VoIP network
requires a client – server topology. An IP PBX is a private branch exchange
(telephone switching system that serves a particular business or office). It can switch
calls between two VoIP users or between VoIP users and a traditional telephone user,
or even between two traditional telephone users. An IP PBX could be a hardware
object or a free and open source software system such as Asterisk. To use a
conventional PBX, separate networks are necessary for voice and data
communications. One of the major advantages of an IP PBX is converged data and
voice networks. This means through a single line for each user, internet can be
accessed, VOIP can be utilized, and traditional telephone communication can be used.
d) VoIP gateway or router
An IP PBX also provides the function of a VoIP gateway, which provides the
conversion interface between the IP network and the traditional public switched
telephone network (PSTN) for fax and voice calls. They usually translate from one
signaling protocol to another.
e) IP phones and soft-phones
This is the terminal of communication which supports VoIP protocols. It can be a
device (hard phone) or an application (soft phone). IP phones and soft phones are
identified by an IP address and compatible with cordless and wireless configuration.
Security with traditional telephone service has never been too much of an issue, but with
VoIP services it could be a different story. Since the call is broken into packets of data
that are carried over the Internet from one location to another, VoIP packet data is
vulnerable to different threats such as eavesdropping and denial of service. But these
threats could be addressed with different approaches.
Eavesdropping is the act of secretly listening to the private conversation of others without
their consent. Encryption is used to address the eavesdropping attack. Encryption means
to make the transfer information unreadable to anyone except those that have a key which
helps to decrypt the information and make it readable again. (Issues and challenges in
securing VoIP, 2009).
Denial of Service (DoS) is an attempt to make a computer resource unavailable. An open-
source IP private branch exchange (PBX) and an open-source VoIP client have
vulnerabilities that would allow hackers to compromise VoIP networks with DoS attacks.
DoS attack could be addressed by:
- Firewalls to filter unwanted traffic.
- Special-purpose hardware (such as routers and switches) that prevents the attacker
from gaining unauthorized access.
- VoIP-aware hardware that can distinguish VoIP traffic.
- Effective authentication systems that can prevent unauthorized access to
- Recovery systems that can recover as quickly as possible after an attack attempt.
(Issues and challenges in securing VoIP, 2009).
Because VoIP integrates with the network, if the network is secured, then the VoIP is
2.3. Quality of Service (QoS)
While VoIP technology becomes more popular, quality of VoIP service is improving.
Quality of VoIP calls will soon be as good as quality of PSTN calls. QoS in IP telephony
means to guarantee that voice packet traffic receives higher priority than other traffic
packets to avoid being dropped or delayed. Poor VoIP call quality could happen for
- Latency: Delay for packet delivery. This could be improved by enhancing the
- Jitter: Variations in delay of packet delivery. This could be addressed by applying
a jitter buffer.
- Packet loss: Too much traffic in the network causes the network to drop packets.
Better connection with better network hardware devices could address this issue.
3. Implementing VoIP for NGOs
NGOs are often challenged by high cost and inflexible telephonic and web based data
services. New technology such as VoIP, which allows the use of the same network for data
and voice, will provide suitable solutions for these challenges. Deployment of any new
application is always a challenge to network administrators and managers. Making the right
deployment decision leads to a successful implementation. VoIP could be implemented using
different approaches, and one of the best ways to implement a VoIP system for NGOs is
using Open Source Software (OSS) components. OSS means free software, and thus there is
no need to buy a license. Asterisk is a popular OSS that is used widely by small businesses,
large businesses, or carriers in implementing VoIP systems. The code of Asterisk was written
by Mark Spencer of Digium, Inc., and contributed to by open source software engineers
around the world. Asterisk recommends running under an open source operating system such
as Linux-Debian or Linux –Centos, but it can also run on a wide variety of operating systems
including Linux, Mac OS X, OpenBSD, FreeBSD and Sun Solaries.
Asterisk provides all the features expected from a PBX. Asterisk has the following features
Drivers for various VoIP protocols.
Drivers for PSTN interface cards and devices.
Routing and call handling for incoming calls.
Outbound call generation and routing.
Media management functions (record, play, generate tone, etc.).
Call detail recording for accounting and billing.
Transcoding (conversion from one media format to another).
Protocol conversion (conversion from one protocol to another).
Database integration for accessing information on relational databases.
Web services integration for accessing data using standard internet protocols.
LDAP integration for accessing corporate directory systems.
Single and multi-party call bridging.
Call recording and monitoring functions.
Integrated "Dialplan" scripting language for call processing.
External call management in any programming or scripting language through Asterisk
Gateway Interface (AGI)
Event notification and CTI integration via the Asterisk Manager Interface (AMI).
Speech synthesis (aka "text-to-speech") in various languages and dialects using third
Speech recognition in various languages using third party recognition engines.
Asterisk supports many VoIP protocols such as H.323, Session Initiation Protocol (SIP),
Media Gateway Control Protocol (MGCP), Skinny Client Control Protocol (SCCP), and
Inter-Asterisk eXchange (IAX2). It is designed to be more flexible and to deal with a wide
range of telephony equipment using relatively inexpensive hardware.
3.1. Implementing a VoIP system for MA’AN
MA’AN Development Center is an independent Palestinian development and training
institution established in January, 1989, registered by law as a non-profit organization.
MA’AN has four branches distributed in Palestine (West bank and Gaza), and its MA’AN’s
headquarters are located in Ramallah. MA’AN’s mission is to work hand in hand with
different NGOs, institutes, organizations and grassroots groups in the poorest and most
marginalized areas in Palestine to improve the quality of life in these areas.
3.1.1. MA’AN network infrastructure
MA’AN’s main office is located in Ramallah. It has two branches (Jenin, Gaza) and two field
offices (Tulkarem, Khan Younis) distributed between the West bank and the Gaza Strip.
Opening a new office is a dynamic process which is influenced by the geographic coverage
of an NGO. The main purpose is to make it close and easier for beneficiaries in that area to
contact MA’AN’s staff. All of MA’AN’s branches / offices are connected to the internet.
Each branch has its own Local Area Network (LAN) and a separate communication system.
For instance, MA’AN’s headquarters runs a traditional circuit switched (SIMENS HICOM1)
PBX which connects to Paltel PSTN. It uses four land lines, three as telephone numbers and
one as a fax number, as well as one Palestinian mobile number through an external GSM
(Global System for Mobile communications) adapter.
3.1.2. Implementation Steps
As previously mentioned in section 2.1, the requirements for VOIP are Internet access, a
computer, and free software. However, when putting a VOIP system in place, one should
consider the quality of the components because it directly affects the quality of service.
MA’AN’s VoIP system was implemented to serve MA’AN’s needs, with the lowest possible
cost. The components used to have a VoIP system running at MA’AN were:
- Internet access: MA’AN has a 4Mbps ADSL connection to the internet.
- A computer ( 2.0GHz quad core processor, 2GB memory, and 250 GB HDD, PCI-
OpenVox A400P04 Analog Interface Card).
SIMENS HICOM PBX is a hardware device that supports a fixed number of extensions.
- Free software (Linux- Centos as an operating system, Asterisk as an IP PBX,
FreePBX, which is web application use GUI (graphical user interface) to control
and manage Asterisk, and X-Lite as a soft phone).
The following steps are the main steps to install the VoIP system:
1. Download and install the operating system (CentOS, http://www.centos.org/) with the
desired version; the latest version is usually recommended. CentOS should be
installed with the following packages selected:
Applications (Editors, Text-based Internet), Development (Development Libraries,
Development Tools), Servers (DNS, Mail Server, MySQL Database Server, Server
Configuration Tool, Web Server), and Base System (Administration Tools, Base).
2. Download and install the four core Asterisk components—Asterisk, Asterisk-Addons,
DAHDI, and LibPRI. (http://www.asterisk.org/)
3. Download and install FreePBX. (http://www.freepbx.org/)
4. Download and install X-Lite, then edit the configuration file to connect to your IP
PBX to be able to make / receive calls. (http://www.counterpath.com/x-lite.html)
See the website www.best-solutions.org for more details.
3.2. Financial benefits
There are more costs involved than a simple phone bill at the end of the month. Costs
include hardware requirements. How does VoIP reduce cost?
An IP PBX uses the internet connection to transfer calls, which means the same line could
carry many calls at the same time, whereas a traditional PBX needs a dedicated line for each
simultaneous call. This feature could save money by reducing the number dedicated lines. In
addition, extending and maintaining a VoIP system is much cheaper than for a hardware PBX
because most of an IP PBX is built on free software rather than hardware as the case in a
A hard copy of bills for MA’AN’s four lines was collected and analyzed for a period of one
year (Jan, 2009 – Dec 2009). Figure (1) shows the total cost of all bills during 2009 for
- Local calls: calls to local landline numbers; mainly MA’AN’s branches / offices.
- Jawwal (Pal mobile): calls to Palestinian mobile numbers.
- Israel Calls (Landline + Mobile): calls to Israeli Landline and mobile numbers.
- International calls.
Jawwal Israel Calls
Local Calls (Palestinian (Landline +
Year 2009 716.5 477.0 896.6 238.9
Figure (1) MA’AN’s headquarter calls cost in 2009
Based on this analysis, MA’AN‘s main office paid $2329 in 2009. In addition, MA’AN pays
$40 per labor hour as fees to maintain the system. In 2009, this fee was $500.
Figure (1) shows that MA’AN paid $716.5 for local calls. With an IP PBX this cost could be
reduced by direct calls between branches through the internet, which brings the cost down to
zero dollars. For calls to Israel (landline and mobile,) MA’AN paid $896.6, the highest cost
in 2009. With VoIP technology, this cost could be minimized by two approaches. First,
MA’AN could use a VoIP provider to transfer calls to Israel. For instance, Skype is one of
the most popular VoIP providers all over the world, and it costs $20 per month to make
unlimited calls to more than 40 countries including Israel. With this option, MA’AN could
save money on both International calls and calls to Israel. Second, MA’AN could use a GSM
adapter with an Israeli mobile number to transfer the calls to Israel. This would be more cost
effective using a Palestinian landline which costs 0.29 NIS per minute compared to the call
rate from a Palestinian landline to Israeli which is 0.75 NIS per minute. Maintaining a
traditional PBX is a hassle and needs both special training and special equipment. While
maintaining an IP PBX is easier, it doesn’t require any new or sophisticated equipment or
special training, and could be done by the designated IT person at the organization.
3.3. Productivity improvements
VoIP opens possibilities that weren't available with traditional phone services. A company
using a traditional PBX system, for instance, is limited by hardware constraints. But the
software in VoIP solutions makes it easier to add features and make improvements along the
way. Voicemail is a feature shared between a traditional PBX and IP PBX. An IP-PBX
improves the way voicemail messages are sent as they are digitally encoded and sent to the
user’s email. This means that users can access, save, delete and forward them using a
computer, in addition to the traditional telephone methods. An IP PBX has unique features
that are not found in a traditional PBX. These features have great advantages in productivity
- Hunt Group: The Hunt Group is a time saving call transfer distribution
mechanism. User extensions are ranked under one communal extension and are
assigned different call priority weights. When the communal extension is dialed,
the user extension with the highest priority weight will ring. On no answer, the
user extension with the second highest priority will ring, and so on.
- Enterprise Instant Messaging (IM): users can promptly communicate with each
other without having to take a telephone call or read an E-mail.
- Call Recording: A reliable and easy-to-use feature, conversations can be recorded
for order verification, quality monitoring and training requirements, and saved to
the user’s voice mailbox for future use.
- Fax handling: IP PBX allows incoming faxes to be received and distributed
Transmitting calls through internet by using VoIP helps NGOs to improve their sustainability. VoIP
1. Lowering telecommunications costs: NGOs can save money on their telephony bills
through broadband connectivity versus a traditional PSTN service.
2. Simplifying Management and Administration: Before VoIP, networks were
comprised of many "proprietary boxes" for voice and data networks that limited an
NGO’s ability to integrate new applications. VoIP, on the other hand, is software, not
hardware, and therefore, it is easier to deploy and integrate new services.
3. Reduced infrastructure costs: Voice and data networks are converged onto a single IP
network, thus significantly reducing infrastructure costs that are associated with a
traditional PBX-based network.
4. Improved employee productivity: VoIP system has unique features that improve the
efficiency of employees, including hunt group, fax handling and on-demand
5. Improved employee access: IP telephony enables remote employees to connect with
the NGO’s phone system from anywhere, thus making them available to make and
receive calls as if they are in the office.
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