. VoIP for Small to Medium- Sized Business (SMBs).......... VoIP for SMBs: Driving the Industry Standard
Introduction Small to medium-sized business (SMBs) are increasingly turning to voice over IP (VoIP) solutions as an alternative to traditional public switched telephone networks (PSTNs.) VoIP is a method by which voice is digitized and transmitted in digital packets rather than using traditional circuit-committed protocols of the PSTN. The IP concept is similar to the PSTN, except that instead of telephones it uses computers, and instead of telephone numbers every VoIP telephone has a unique MAC (Media Access Control) address associated with an IP Address. Thus, IP telephones use IP addresses. Probably the most significant difference with VoIP, as compared to PSTN, is that backbone-trunking resources are not assigned in a dedicated, predictable manner to support a voice call. Instead, trunk bandwidth for a VoIP telephone conversation is assigned on a random, as needed basis, via packet switching. Advanced IP telephony includes many enhanced features, such as voicemail, conferencing, presentation viewing, and unified messaging for cell and PDA devices. The overall quality and reliability of VoIP has increased dramatically in recent years, making it comparable to the level of service provided by PSTNs. SMBs are especially attracted to VoIP because of cost savings they can incur by leveraging a single IP network to support both data and voice services. Voice protocols have also evolved to offer more robust features, value-adds, and high-margin services that are all critical to SMBs. The purpose of this paper is to describe what VoIP can do specifically for SMBs. This paper defines what it means for SMBs to deploy VoIP and how they can take advantage of the many benefits. The intent is to begin defining a working standard for SMB VoIP solutions, which will help solidify VoIP networks as secure, reliable, and high performance solutions. Finally, this paper describes the steps Bandwidth.com takes to drive SMB industry standards regarding VoIP network solutions. 2
What s the Big Deal About VoIP for SMBs? This service allows SMBs to gain control over communications expenses and management difficulties associated with traditional PSTNs by migrating to a new network-based hosted solution. SMBs are attracted by lower-cost telephony services while network operators are eager to leverage the flexibility a single IP network offers. SMB customers demand one thing from their VoIP solution a high-quality, reliable, end-to-end service to connect to and from anywhere in the world. A major challenge to the longterm success of VoIP is guaranteeing positive customer perception of Quality of Service (QoS) at a reasonable cost. Full network visibility driven by SMB industry standards is required to achieve this goal. Before deploying a VoIP solution, an SMB should consider 5 critical points: quality, reliability, usage, cost, and features offered. Without proper due diligence, an SMB may face service that does not reliably meet its needs at the required level of quality. Defining Quality Standards How an SMB perceives the overall QoS of a VoIP system is critical to defining a quality standard. VoIP services must not have a noticeably lower performance rate than other traditional PSTNs. Voice quality is a function of many factors and may include things such as delay, echo, jitter, and packet loss. From a user s viewpoint, perceived performance consists of things such as voice quality, successful call completions, and dial tone success ratio. Global reach must also be guaranteed by VoIP networks, regardless of complexities caused by moving between technology domains. Achieving the highest quality VoIP access is a process the network operator must plan carefully. Managing such networks is a complicated matter requiring effective communication among operators. Operators must create a plan that includes strategies to achieve full visibility with little effort required. 3
Factors Affecting VoIP Quality Standards Defining standards to measure voice quality in conjunction with availability detection can enhance VoIP. As a result, a well-managed network plays an essential role in keeping a VoIP system up and running properly. The following sections describe two important classifications that should be considered when defining quality standards for VoIP, latency and jitter. Latency From a PSTN viewpoint, latency can be described as the amount of time it takes a caller s voice to reach the listener s ear. The larger the latency value, the more likely it is for a lack of synchronization between speakers. Although a larger latency value does not necessarily degrade the overall sound quality of a call, it may promote hesitation in the participants interactions during a call. Industry standards suggest that end-to-end latency should be kept to a 150 ms maximum. Network operators must take into consideration the various causes of latency delay to ensure the delay remains below 150 ms. Packetization delay: amount of time it takes for endpoints to create packets used in voice services. The larger the packet size, the greater the amount of time it takes to fill. While packetization delay is governed by the CODEC standard being used, nominal operation should not exceed 30 ms. Serialization delay: amount of time it takes to serialize digital data onto physical links of interconnecting equipment. Generally speaking, the faster the media, the lower the latency. Propagation delay: amount of time it takes a signal to traverse the length of a conductor. While there is always going to be some level of propagation delay, it is only an issue when the signal travels a great distance. Queuing delay: amount of time a packet remains buffered in a network element while awaiting transmission. Packet forwarding delay: amount of time it takes for a network device to buffer a packet and make the forwarding decision. This delay is variables and depends on the function and architecture of the networking device. 4
Jitter Jitter is the measure of time between when a packet is expected to arrive to when it actually arrives. Queuing variations caused by dynamic changes in network traffic loads is a major cause of jitter. Packets that take different equalcost links not physically the same length as other links is another cause and can disrupt VoIP quality. Play-out buffers shield media gateway packet streams so that voice quality is not as affected by packet jitter. While jitter cannot be completely eliminated, play-out buffers can help minimize its effects; thus increasing the overall voice quality of a VoIP transmission. Working Towards a VoIP Quality Standard A number of factors should be taken into consideration when defining a quality strategy for VoIP networks. The following sections discuss key initiatives to use when developing a quality strategy for a VoIP network. Perceived Voice Quality One of the most valuable methods to understanding the correlation between voice quality and network behavior is to monitor and track network and service behavior with a high degree of granularity. By analyzing this data, operators can identify areas of the network that are causing service degradations. There are several components involved in monitoring voice quality: Listening quality: speech quality or clarity in one direction from point A to point B. Side tone quality: terminal equipment s ability to produce a suitable side tone without echo. Conversational quality: how well interaction from point A to point B and back again works. Overall voice quality: sum of the above. Performance Metrics for VoIP Networks While monitoring all calls in a VoIP network can be an invaluable tool, other service metrics should be used as well to measure quality performance. Service-centric metrics based on signaling analysis have proven to be invaluable to high quality voice services. Tracking performance metrics should be done with a fine granularity. For example, it is recommended that a sampling 5
rate of no more than 5 minutes should be used to catch QoS changes. Some typical performance metric definitions are as follows: ABR: Answer to Bid Ratio - Answered Calls divided by Attempted Calls in a given time period. ASR: Answer to Seizure Ratio - Answered Calls divided by voice circuits successfully captured. CSR: Call Success Ratio - successful call signals divided by attempted call signals; provides a good determination for how well network signaling is working. CST: Call Setup Time Defined as: time from last dialed digit to reception of Ringing Tone, is sometimes also referred to as Post Dialed Delay. For a well dimensioned network this figure of merit should be 150 ms or less. NER: Network Efficiency Ratio Defined as: ASR/ABR and thus taking the user behavior out of the equation. It gives the percentage of successful allocation of a voice circuit i.e. an indicator of congestion in the network. Should be very close to 100%. Integrated Customer Access Granting customers access to easy-to-use self-service tools should be part of the overall quality strategy. Ideally, all endterminal devices should have built-in measuring and reporting capabilities that will enable customers to report issues to network operators. However, standardized reporting from some types of terminal devices is a long way off. Until then, some type of tool providing VoIP endpoint testing that can easily integrate with the monitoring system should be made available. Differentiated VoIP Service Offerings Since VoIP of reasonable quality is already available via the Internet at practically no cost, vendors must differentiate their offerings to attract more customers. VoIP customers require solutions whose service is predictable and as easy to use as a traditional PSTN. Many new opportunities are created for voice-related services, including: Convergence of voice and PC-based services. Instant Messaging and the integration of voicemail and Outlook calendars are two prime examples of promising business potential. Demand for constant reliability. The demand for constant availability will require monitoring strategies to be implemented for these services in order to ensure a high level of quality. 6
Security issues. Security concerns are raised with regards to IM, especially, as messages are moved across firewalls. Performance and service predictability also become concerns. Detection of Unwanted Behavior As the focus of a quality VoIP system rests largely on overall user perception, annoying factors that proliferate email systems (i.e., spam) should not be allowed to migrate to VoIP. Network-wide monitoring systems can detect unwanted behavior in real-time such as spam, other unwanted mass call events, and fraudulent behavior. Defining Reliability Standards How an SMB perceives the reliability of a VoIP system is also critical to defining a quality standard. An SMB relies heavily on effective and readily available communication systems to optimize their business processes. Any deterioration of that service can strain an SMB s resources. Problem detection is an important part of VoIP performance management. Although network failures are rare, network operators must plan for them nonetheless. Failover strategies must be developed and implemented to accommodate network device malfunctions or broken links. Organizations should consider deploying redundant links and/or equipment to ensure uninterrupted service. Organizations can decrease the likelihood of a large service interruption by having media gateways and controllers that can actively detect their status in real-time. Link failures could also be immediately detected and devices could take appropriate actions by connecting the media gateway and controller to the router. Another option for increasing reliability could be to implement failover as a redundancy mechanism. Finally, realtime monitoring and proactive fault identification can improve system reliability. 7
Defining Usage Standards Organizations with a converged voice and data network should determine how much usage bandwidth should be set aside for each service. Such a decision is based on careful consideration of the organization s priorities and total available bandwidth. If too little bandwidth is allocated for voice service, unacceptable quality issues may arise. Voice service bandwidth should take priority over other services by utilizing QoS packet prioritization, as voice services are more susceptible to noticeable degradation due to bandwidth depletions. Network bandwidth allocations are based on projected numbers of calls at peak hours. Using the CODEC g711 coding method, each VoIP call will utilize 85kb of data. Voice usage will be determined by taking the product of projected calls during peak busy hours and the voice data packet of 85kb. This total amount will be the minimum requirement for successful call completion with VoIP service. If this minimum amount is not met, there will be service degradation with VoIP service. Defining Cost Standards The cost-effectiveness of VoIP is initially very attractive to SMBs when looking at voice service options. SMBs can gain efficiencies by only having to support a single network infrastructure. By using a single packet-switched network, as opposed to managing both packet and circuit-switched networks, SMBs can also reduce maintenance and management costs. The same technical staff can operate both voice and data networks instead of requiring different resources with different areas of expertise. 8
Defining Additional Feature Set Standards Implementing VoIP offers a number of compelling benefits for SMBs. Considerable cost savings coupled with new attractive integrated features provide an attractive alternative. VoIP has the possibility to deliver additional features that will enhance user productivity and appeal. Such features might include: Unified messaging options Advanced call routing Integrated information services Computer system integration Long-distance toll bypass Encryption Common network infrastructures also make it possible to integrate other media services. For example, imagine that a person is always reachable using the same number regardless of their geographical location. Integration with video media, electronic white boards, or customer relationship management (CRM) software are other viable options. 9
How does Bandwidth.com address these areas? BandwidthVoice is Bandwidth.com s hosted VoIP local and long distance service for SMBs. This solution includes a hosted PBX, which eliminates the need to install expensive PBX hardware at a customer site. As a Level(3) Communications, Inc. certified partner, BandwidthVoice is comprised of a suite of enhanced voice and data services hosted on the Level(3) nationwide platform. This service creates a virtual working environment by connecting all company locations and remote employees with the same dialing plan, allowing intra-company 4 or 5-digit dialing and forwarding of calls and voicemail messages between locations. With BandwidthVoice, users can manage all of their office communications needs through any Internet access, browser, or wireless device. Driving Industry Quality Standards BandwidthVoice is designed to increase your operational efficiency and enhance the quality of your business s voice services. By combining an Edgewater QoS device with tier 1 Internet connectivity, BandwidthVoice assures you have the highest quality voice system. We will determine the correct bandwidth required for the number of users, as well as conduct an evaluation of the customer s LAN. Therefore, the system will be provisioned and installed to ensure voice quality and the number of users and/or data being transmitted won t have an effect on voice quality. BandwidthVoice is transmitted over a managed IP network, not the Internet. As this network is engineered for voice traffic, if the Internet is busy, it will not have a negative effect on user voice quality. BandwidthVoice guarantees 55 ms average time for IP packets to travel over the Bandwidth.com core network (between Bandwidth.com North American Gateways), presented in milliseconds and guaranteed for each calendar month. BandwidthVoice also guarantees 99.5% network packet delivery over the Bandwidth.com core network 10
(between Bandwidth.com North American Gateways), presented as an average percentage of packet loss vs. successful delivery and guaranteed for each calendar month. Driving Reliability Standards As more SMBs migrate to high-speed, sophisticated network infrastructures to support VoIP services, system reliability remains a fundamental concern. While dropped packets are not a major problem in ordinary data communications, they can greatly hamper real-time voice conversations. As a result, BandwidthVoice offers a more sophisticated monitoring solution through its Service Level Agreement (SLA) service. The service is engineered to be as reliable as any other carrier-grade network product. Since all of the data is stored in the network, the data itself is intact. The system has been tested to have five 9s reliability (99.999% availability), including (and especially) customer data. In the event of a backbone network failure, the impact on service is very limited, if at all perceptible. In fact, this system was designed to isolate failures from the users, so any calls that are in progress will remain up in the event of a failure. Extensive network monitoring ensures that any local failures (for example, phones or LANs) are minimized when they do occur. Driving Usage Standards To ensure the best service possible, Bandwidth.com employs the following unique customer service tools accessible through its customer service portal: Pricing Portfolio provides price quotes from every major carrier that offers service to a customer s location. Installation Advantage lets customers monitor the progress of their installations online. In addition, they have access to Bandwidth.com s experienced provisioning team to help answer questions and troubleshoot any difficulties during the installation process. Trouble Ticket Accelerator enables the customer to place a trouble ticket directly with the carrier, but lets them leverage Bandwidth.com s partnership to get quicker resolution. 11
Driving Cost Standards BandwidthVoice provides SMBs with a complete Internet, local, and long distance solution with enterprise-grade features and guaranteed levels of service at only a fraction of current costs. BandwidthVoice costs are predictable at an unlimited flat rate of $39.99 per seat. Other attractive cost standards include: Reduced costs of up to 40 percent resulting from simple calling plans, free calls between locations and reduced operations costs; Streamlined administration resulting from pointand-click tools, eliminating the need for costly maintenance and support; Enhanced scalability that allows new users to be added as businesses grow without having to buy new switches or cards. Driving Standard Feature Sets The BandwidthVoice solution offers shared features that result from a hosted environment, which ensures SMBs and their remote locations all operate on the same platform. Enhanced functionality typically associated only with high-end PBX systems is delivered with BandwidthVoice. Standard CLASS 5 and PBX functions include: Local calling Long distance calling Voicemail Unified Messaging Audio and Web conferencing Web-based Office Administrator tool Web-based Personal Communication Manager tool Other key features include Flexible Feature Mapping such as handset volume control, hands free dialing and hook flash; Personal Locator such as find me/follow me function that forwards up to three numbers; Unified Messaging that provides a single point of integration for voicemail, e-mail and fax messages; and a Plug-in for Microsoft Outlook. 12
About Bandwidth.com Bandwidth.com is the largest business Internet provider in the United States, offering a network capable of delivering business-class Internet connections to more locations nationwide than any other provider. Over the past five years, Bandwidth.com has revolutionized the acquisition of Internet access for small to medium sized businesses. As the marketleading intermediary between telecom providers and customers, Bandwidth.com has created a new way for businesses to purchase Internet access. Through its relationship with leading telecom providers, Bandwidth.com offers unparalleled selection, price and service. The company s unique methodology and experienced team ensure accountability and service superior to traditional Internet access providers. Bandwidth.com has met the Internet access needs of nearly 2,000 customers, selling more than $2.5 million of data connectivity monthly. Founded in 1999, Bandwidth.com is located in Research Triangle Park, North Carolina. For more information, visit www.bandwidth.com. 13