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Selecting VoIP for Your Enterprise



Service Provider Summary Glossary 3 3 4 4 5 6 6 7 9 10 Copyright ©2005 Technology Marketing Corporation. All rights reserved.Selecting VoIP for Your Enterprise Prepared for Global Knowledge by Technology Marketing Corporation Table of Contents Introduction Cost Savings and Other Benefits Potential Pitfalls and How to Overcome Them Voice Quality Security Emergency Services/911 Network Outages Deployment: In-house vs. Page 2 .

For example. VoIP enables seamless call transferring to experts across a connected enterprise. but they must do some research to decide if VoIP is right for them. whether they are in the same building. Enterprises of all sizes can benefit from this technology. voice mail.000 annual savings in operational expenditures over their previous system. By using the company’s data network. By simply dialing a coworker’s extension. There are also so-called "soft" benefits enabled by VoIP. Copyright ©2005 Technology Marketing Corporation. the market for enterprise VoIP will grow to $7. By converting voice into packets and transporting these packets over an IP network. Productivity enhancing applications such as conferencing. so too do the telephony applications that employees at the main corporate location enjoy. Which vendor should I call? Would I rather deploy and manage my telecommunications in-house.Introduction Voice over Internet Protocol (VoIP) is a process of digitizing and sending voice telephone signals over the Internet or other data network.3 million dollars on a new VoIP network to serve over 2. For many enterprises. you can speak to a distant colleague as if he or she were in the very next cubicle. If the data network reaches a remote location. However VoIP is more than a plan to lower a company’s phone bill.000 phones. Furthermore. unified communications. be it a private WAN or the Public Internet. and how much money can I save in the long run? The first thing most people realize about VoIP technology is that it can save their business money by reducing or eliminating the toll charges for long-distance and even local calling. Of course. and click-to-dial are all enabled across the enterprise. Cost Savings and Other Benefits The main benefit of VoIP technology is that it is a cost-saver. or does it make sense to outsource to a hosted services provider? How much will this cost. they can have all locations served by a single IP PBX. The city is now enjoying a $700. and lower operational expenditures as a result of simplified management schemes. that is enough of a reason to consider VoIP. or across the globe. thus enabling extension dialing between far-flung locations. enterprises can eliminate all costs associated with calling between branches. Ontario. This presents a tremendous opportunity for numerous vendors to supply products and services to this market. corporations are able to avoid the Public Switched Telephone Network (PSTN) and the associated tolls. cost savings come in many ways. According to the Probe Group. In the case of an enterprise with multiple branch offices. Tremendous cost savings come in the form of lower telephone bills. All rights reserved.1 billion in 2008. Page 3 . in the case of Mississauga. this is especially true. But managing the system is simplified due to eliminating the need to monitor multiple networks. the city spent $3. such as increased worker productivity. This paper serves as an introduction to VoIP (its benefits and potential pitfalls) and provides insight into the various options available to enterprise decision-makers who face the task of selecting a VoIP-based phone system. the ability to collaborate among multiple branch offices. across town.

In so-called "greenfield" deployments. Jitter — (1) Jitter is a small. For the vast majority of enterprises considering running voice traffic over their data infrastructure. A thorough understanding of the potential return on your investment is necessary to ensure that the migration to VoIP is a cost-effective endeavor. It may not take much work to physically move a single phone or to set up a new employee’s voicemail system. here are the three culprits defined: Delay — The amount of time it takes for a signal to transfer or for the time that is required to establish a communication path or circuit. While that has been a problem in the past. it is becoming less of an issue. When the received pulse waveform is displayed on an oscilloscope screen. Any problems that pop up in early phases of deployment can be worked out before migrating the next group of users. Furthermore.By combining separate voice and data networks into one network. and changes. jitter. rapid variation in arrival time of a substantially periodic pulse waveform resulting typically from fluctuations in the wave speed (or delay time) in the transmission medium such as wire. there is no need to run two separate network cables (one each for voice and data). (2) The short-term variation of transmission delay time for data packets Copyright ©2005 Technology Marketing Corporation. in order to maintain a healthy measure of control over the transition. All rights reserved. Let’s take a look at some of the more common problems experienced in a VoIP call: delay. VoIP enables cost savings from a network infrastructure perspective as well. In fact. cable. allowing companies to migrate to VoIP slowly. network administrators need manage only the single converged network. and latency. adds. individual pulses appear to jitter or jump back and forth along the time axis. department by department. Page 4 . The costs add up quickly. adds. a network assessment is in order. Many enterprise VoIP solutions allow administrators to manage the system via a web-based browser interface and enable managers to enact changes to an employee’s phone and voice mail settings remotely. Another benefit of VoIP is that many enterprise telecommunications systems are upgraded in a piecemeal fashion. VoIP also reduces the cost and complexity associated with moves. VoIP practically eliminates that expense. According to Tehrani’s IP Telephony Dictionary. or optical fiber. many VoIP deployments claim to have voice quality of service that is in some respects better quality than legacy communications. Still the problem does not simply go away. All without the need to call the phone system’s manufacturer to send a representative to make those moves. There are still impediments to voice quality that need to be addressed. Potential Pitfalls and How to Overcome Them Voice Quality A serious reservation most people have is the belief that the quality of VoIP is inferior to that of traditional telecommunications. In fact most businesses will need to spend some capital to upgrade their networks to be capable of delivering a consistent high-quality voice experience. and changes. but imagine an organization that employs thousands of people across multiple locations.

As you can see. Toll quality telephone service is generally granted a MOS score of 4. Unacceptable! According to the International Telecommunications Union. the variance of interpacket arrival times. Some industry professionals believe that VoIP in the context of network security needs to be addressed as simply another data application on that network. Voice quality is calculated by a measurement called MOS. The MOS rating system is judged on a five-point scale where a score of 1 implies poor quality. (3) In IP telephony. Still others believe that VoIP has a number of peculiarities that demand more specific attention. This measurement is determined by an actual group of human listeners who rate the quality of audio on samples played to them. Latency — Latency is the amount of time delay between the initiation of a service request for data transmission or when data is initially received for retransmission to the time when the data transmission service request is granted or when the retransmission of data begins.0. All rights reserved. As such. eavesdropping is of great concern to executives who would prefer their phone calls to be as secure as possible. Security Security is another critical issue facing enterprises interested in deploying VoIP. acceptable delay for VoIP calls can be described as follows: • 0 to 150 milliseconds is acceptable for most any application. or mean opinion score. • 150 to 400 milliseconds is acceptable for international connections. Copyright ©2005 Technology Marketing Corporation.that usually results from varying time delays in transmission due to different paths or routing processes used in a packet communication network. If troublemakers were to break into a company’s voice system. it’s important to separate voice equipment behind firewalls—frequently updated with the latest patches and monitored to keep an eye-out for intruders. Certainly this is an area that needs to be addressed in any network deployment of voice. So it is imperative to employ a quality of service solution that keeps the delay to an absolute minimum on the originating side of the call. Other concerns include the "hijacking" of a voice gateway to place unlimited unauthorized free calls across the globe. all of these terms deal with the impediment to transmission of VoIP packets. vast amounts of potentially sensitive data would be at risk. and a score of 5 is excellent. Most VoIP solutions are deployed on servers that run either proprietary operating systems or on commercially available servers such as those offered by Microsoft. Keep in mind that delay can creep in at many points throughout the network that are beyond your control. Now imagine that same delay in the middle of a conversation. That delay is imperceptible to the end user. And delayed or missing packets spell doom to quality VoIP communications. and as such is the goal to strive for. These servers are as susceptible to hacking or denial-of-service attacks as any other servers deployed in an enterprise IT department. Page 5 . Consider that if you send an e-mail that arrives with a two-second delay. Also.

Customers have an expectation that they can reach you whenever they need to. there are a number of concerns for enterprises that should be addressed. keeping a close eye on your network through the use of an intrusion protection solution. and having that information transmitted to the PSAP. Even if that employee switched offices and took his or her IP phone. All rights reserved. Page 6 . Emergency Services/911 One of the more pressing concerns facing VoIP is the issue of emergency services such as 911. VoIP phones demand a power source within the enterprise. developers are tasked with the challenge of making sure that the speed of innovation does not outstrip the ability to supply emergency services to users of VoIP. Another issue involves funding of emergency 911 infrastructure. When selecting a VoIP phone system for your enterprise. or simply chooses to work from home? If an emergency call is placed to 911 from the caller’s new location.) to make sure no unauthorized users can place calls if they are able to breach the firewall and get inside the network.The use of computer-based softphones. companies that are switching to VoIP have the expectation that their phone system will perform at least as well (if not better) than their legacy systems. who uses a softphone. and even IP handsets. As VoIP enjoys rapid deployment. User access should be controlled through password protection. also leaves an enterprise open to a security breach. There is concern among public agencies that system funding will come under attack as enterprises drop legacy phone services and deploy VoIP. VoIP users can avoid paying appropriate 911 surcharges while still using the service provided by their VoIP service provider. and taking precautions to secure your servers as you would for other critical business infrastructure and applications. But what happens when that employee. While many consider this to be a service provider or residential customer concern. making sure your firewalls are properly configured. it is necessary to factor this into your selection criteria. and it is extremely rare for these phone systems to suffer outages due to problems with supplying electricity. Likewise. travels to another city. If Copyright ©2005 Technology Marketing Corporation. which is not a problem. One current limitation of VoIP is that the caller ’s physical location is not broadcast to the emergency services’ PSAP (public safety answering point). And phones might even be limited as to what type of calls they can place (international. These devices should be encrypted. 900 number restrictions. This way emergency services workers can respond to the exact location of an injured employee. the phone systems will not work. Other general suggestions for protecting your voice traffic from security threats include: making sure to encrypt the voice stream. Enterprises can work around this shortcoming by assigning a physical location to each phone. This is not the case for VoIP phone systems. A business’ phone system is critical. chances are emergency service personnel will respond to the main office location—wasting time and valuable resources deployed to the wrong location. etc. Network Outages Traditional telephone systems are powered over the lines that are drawn from the local phone company’s central office. chances are the physical location would be in the same building. The problem is that when power is interrupted.

Page 7 . high-quality power that will not degrade the telecom equipment. The decision depends on what’s right for your enterprise. This will help response time. With either choice. it amounts to nothing. a remote monitoring system will allow you to see if there are any power issues within your network. Gartner. Furthermore. Service Provider While there are many choices when it comes to enterprise VoIP. With IP Centrex. Other power issues revolve around supplying power to the individual phones that reside on people’s desks. resides at the remote IP Centrex site. whether IP telephone. Individual users probably will not even know or care if their company has IP Centrex or an IP PBX. Lastly. Some of the solutions a business needs to look into are an uninterruptible power supply (UPS). Users do not own the equipment. it is important to make sure that there are no disturbances in the power supply or else the quality may be affected at the branches. These devices come with a varying amount of battery backup power. without the need to modify the existing infrastructure. with either system. Furthermore. and it is imperative that you ask your provider to explain how they work and why they are important. Deployment: In-house vs. They just want to know that their phones work.a new phone system with all the bells and whistles promised by VoIP sits idle for lack of a well thought out power plan. and in fact most of the equipment. users buy the equipment and maintain it at their site. Copyright ©2005 Technology Marketing Corporation. Among the benefits provided by this technology is that it obviates the need to run power and data cabling to each desktop phone location. All rights reserved. predicts that business lines supplied as part of local VoIP carrier services in the United States (which includes IP Centrex) will grow at an 83 percent compound annual growth rate (CAGR) out to 2008. with the exception of the telephones. As with buying or leasing a car. an industry analyst firm based in Stamford. giving users access to the office telephone system remotely or at the company. Power over Ethernet is able to supply power and data to IP phones. or wired phone. redundant systems. you should consider outfitting your branches with UPSs in case localized power outages occur. Gartner also predicts strong growth in the enterprise IP telephony space with a 34 percent CAGR of Pure IP-PBX line shipments out to 2008. the features reach across the network. Essentially. softphone. this solution maintains power to the telephones for as long as the battery backup remains active. If multiple branch offices are served from a central server. in the end the basic decision boils down to deploying the solution in-house versus having a service provider supply the solution in a hosted fashion (IP Centrex). With IP PBX. Both approaches are viable. as well as other devices over existing LAN wiring. not at the user site. and increase the ability to nip any problems in the bud. it is like leasing. you still get phone services and equipment with similar voice quality and reliability. A UPS will continue to supply power to the phone system for a limited time until the main power is restored. regardless of geography or type of telephone. Power over Ethernet solutions abound. CT. when used in conjunction with a UPS. and remote management and monitoring.

The jury is still out on what the best solution is for a company with multiple sites. Page 8 . There is not a steep upfront cost—but the cost is ongoing. What it really comes down to is preference: • If you want to own it a long time. or changes. IP Centrex can usually reroute calls very swiftly. However. users can be connected very quickly in the event of a disaster. The one advantage IP PBX systems have is that because users can set it up themselves. For users concerned with disaster recovery and survivability. billing a contracted monthly rate plus a variable rate for additional services. the upfront cost can be significant or it can be financed to make it more affordable. There is no doubt that ownership equates control. Geography does not matter. For maximum survivability. whether it’s an IP PBX or IP Centrex. With an IP PBX. buying an IP PBX may make more sense. Copyright ©2005 Technology Marketing Corporation. the IP PBX might be cheaper in the long run. it is typically less expensive to add new users than with IP Centrex. IP Centrex providers charge much like a wireless provider. the system. if it occurs at the client site. users can move the phones wherever there is Internet access without the traditional service charges for moves. Choosing a vendor plays a key role. but it also means that there is a learning curve. there isn’t a clear winner. What does matter is the vendor’s reputation and track record for quality. say more than five years. it becomes a major issue for the enterprise. they can basically function as nodes off the home office’s IP PBX or from the IP Centrex. needs to be redundant and not physically co-located. The upside is that once the system is running smoothly. and because the IP phones can be plugged in anywhere. IP Centrex may be the best way for them to get the benefits of IP telephony. they have the control to establish the level of potential disaster recovery that is a priority for their business. Since IP phones or softphones can be plugged in anywhere there is Internet access. reliability. adds. it should stay that way for a very long time.With IP Centrex. and learn how to use the system. As well. both IP Centrex and IP PBX are very reliable systems. Today. security features have become a major consideration in today’s telecom decision. For companies that do not have the staff or bandwidth to implement an IP PBX. Owning an IP PBX means there is a significant up-front commitment to install. and overall feature set. especially if it comes with the ability to migrate to future systems and/or grow to accommodate the company’s growth. Calls need to be automatically rerouted when the system goes down. In fact. without any geographic limitations. With either IP Centrex or IP PBX. maintain. With either system. It all depends on where the disaster takes place. companies can have IP telephony in as many offices or home offices as they’d like. if the disaster happens at the IP Centrex Switch. All rights reserved. For IP PBX systems. All these considerations should be factored into the total cost of ownership. IP Centrex systems are also very reliable during a disaster. As with leasing cars. because the provider of IP Centrex services can be based anywhere and still provide services. the user pays on a periodic basis. because all the data and infrastructure is already built into the telephone system. if a company plans to keep its system for a while.

IP Centrex might not cost you as much up front and you can contract for less time.com or call 1-800-COURSES to speak with a sales representative. Summary VoIP is proving to be a viable new alternative to traditional telecommunications solutions in the enterprise. VoIP offers many benefits. one needs to do some research before deciding on how to proceed. hands-on labs offer practical skills and tips that you can immediately put to use. and many potential pitfalls that you need to be aware of before making the final move to VoIP. • If you want special services or customization. calls out) use IP Centrex. your migration to VoIP should be a positive experience. • If you want basic services (calls in. visit www. Choose from our more Copyright ©2005 Technology Marketing Corporation. and sharpen your competitive edge. buy the IP PBX. Both approaches are viable. yet both have their drawbacks. The decision depends on what’s right for your situation. and as with any major decision. Consider the trade-offs and be clear on what you really must have in your system today and into the future. which approach works best: hosted or in-house. Check out the following Global Knowledge courses: Voice over IP Deploying VoIP in the Enterprise Converging Voice and Data Networks Cisco Voice over IP Telecommunications Fundamentals I Telecommunications Fundamentals II For more information or to register. Enterprises need to figure out if VoIP is right for them. Page 9 . VoIP is the future of enterprise telecommunications. If you arm yourself with the right questions and a thorough understanding of your needs. enhance efficiency. Our courses and enhanced. And if so. as businesses who are shopping for phone systems are increasingly turning to VoIP as their first choice. Learn More Learn more about how you can improve productivity.globalknowledge. But there are many elements to consider when selecting an enterprise VoIP phone system. But telecommunications is the lifeblood of an enterprise. All rights reserved. from lower ongoing telecommunications bills to soft benefits such as increased worker productivity and the ability to conduct ad hoc collaborative sessions across multiple locations. Our expert instructors draw upon their experiences to help you understand key concepts and how to apply them to your specific work situation.• If you want to keep the system a shorter time.

audio. CLEC — Competitive Local Exchange Carrier. and subsequently recovering the original data (decoding). The service pedestal is said to be "at the subscriber's curb. Firewalls vary in the amount of buffering and filtering they are capable of providing. IP Contact Center Summit. WiFi Telephony Magazine. TMCnet. and Internet Telephony.g. The fiber optic transmission is used to provide broadband services beyond the central office. the Internet). e-Learning. and it usually refers to lossy compression. TMC is also the first publisher to test new products in its own on-site laboratories. FCC — Federal Communications Commission Firewall — A firewall is a data filtering device that is installed between a computer server or data communication device and a public network (e. Speech-World Conference. Alternative Power.tmcnet. Page 10 . Speech-World. or video. The fiber optic transmis- Copyright ©2005 Technology Marketing Corporation. and On-site sessions." FTTH — Fiber to the home. and The Global Call Center Outsourcing Summit. TMC also produces The VoIP Developer Conference. FTTC — Fiber to the curb. SIP Magazine. Codec — Coder/Decoder A technique for compressing information to a fewer number of bits for more efficient transmission and storage (coding).com. Delay — The amount of time it takes for a signal to transfer or for the time that is required to establish a communication path or circuit. A distribution system that uses fiber optic cable to connect telephone networks to nodes that are located near homes or any business environment (near the curb). WiMAX Magazine. Glossary CAGR — Compound annual growth rate. A firewall continuously looks for data patterns that indicate unauthorized use or unwanted communications to the server. TMCnet. For more information about TMC. About Technology Marketing Corporation Technology Marketing Corporation (TMC) publishes two magazines: Customer Inter@ction Solutions. all the way to the last 50-100 feet from the subscriber. Normally the term codec applies only to compression of human-perceived signals such as speech.com publishes more than 25 topical online newsletters. Planet PDA Magazine. CTI — Computer Telephony Integration. to meet your IT and professional skills training needs. TMC Labs.than 700 courses. and BiometriTech. The year over year growth rate of an investment over a specified period of time. delivered through Classrooms. and the online publications. images. A distribution system that uses fiber optic cable to connect telephone networks to nodes that are located in the homes of customers. visit its web site at www. A telephone service company that provides local telephone service that competes with the incumbent local exchange carrier (ILEC).com. All rights reserved. WiFi Revolution. VoIP Developer.

whereas their successor is designed for converged applications. MEGACO.711 — A standard analog to digital coding system (coded) that converts analog audio signals into pulse code modulated (PCM) 64 kbps digital signals. and data between a pair of videoconferencing workstations. IPBX systems use a IP telephone server to provide for call processing functions and to control gateways access that allows the IPBX to communicate with the public switched telephone network and other IPBX's that are part of its network.729 — A low bit rate speech coder that was developed in 1995.323. The G. and potentially a richer feature set. A telephone carrier (service provider) that was operating a local telephone system prior to the divestiture of the AT&T bell system. There are two versions of G.729: G. Current IP PBX offerings vary in their range of features and network configurations. call transfer. G.729 and G. IP PBX represents the evolution of enterprise telephony from circuit to packet. IP Centrex allows customer to have and use features that are typically associated with a private branch exchange (PBX) without the purchase of PBX switching systems.711 is an International Telecommunications Union (ITU) standard for audio codecs. H. The G. ILEC — Incumbent local exchange carrier. G.711 standard allows for different weighting processes of digital bits using mu-law and A-law coding. voice mail waiting indication and others. as well as procedures for breaking data into packets and synchronizing transmissions across communications channels. Page 11 . These features include 3 or 4 digit dialing. The G.723 — An International Telecommunication Union (ITU) standard for audio codecs that provides for compressed digital audio over standard analog telephone lines. Copyright ©2005 Technology Marketing Corporation. all the way through the drop wire to the optical node that is located in the customers home.sion is used to provide broadband services beyond the central office. mainly in terms of reduce Opex (operating expenses). IP Centrex — IP Centrex is the providing of Centrex services to customers via Internet protocol (IP) connections. IP PBX — A private local telephone system that uses Internet protocol (IP) to provide telephone service within a building or group of buildings in a small geographic area. video.729 A. Traditional PBX systems are voice-based. All rights reserved.323 specifies techniques for compressing and transmitting real-time voice. It has a relatively high voice quality level for the low 8 kbps data transmission rate. but offer clear advantages over TDM-based PBX. G.711 standard was approved in 1965.323 — H. intercom features. IPBX systems are often local area network (LAN) systems that interconnect IP telephones. H. IP PBX supports both voice and data. MGCP. distinctive line ringing for inside and outside lines.323 is an umbrella recommendation from the International Telecommunications Union (ITU) that sets standards for multimedia communications over Local Area Networks (LANs) that may not provide a guaranteed Quality of Service (QoS). IPBX systems can provide advanced call processing features such as speed dialing. It has low delay due to a small frame size of 10 msec and look ahead of 5 msec. and SIP. and voice mail along with integrating computer telephony applications. Some of the IPBX standards include H. It also describes signaling protocols for managing audio and video streams.

LAN — Local-area network Latency — Latency is the amount of time delay between the initiation of a service request for data transmission or when data is initially received for retransmission to the to the time when the data transmission service request is granted or when the retransmission of data begins. maximum bit error rate (BER). MOS — Mean opinion score (MOS) is a measurement of the level of audio quality. RBOC — Regional Bell Operating Company. PBX — Private Branch eXchange. rapid variation in arrival time of a substantially periodic pulse waveform resulting typically from fluctuations in the wave speed (or delay time) in the transmission medium such as wire. QoS — Quality of service (QoS) is one or more measurements of desired performance and priorities of a communications system. PSTN — Public switched telephone networks are communication systems that are available for public to allow users to interconnect communication devices. When the received pulse waveform is displayed on an oscilloscope screen. and associated operations support systems that allow communication devices to communicate with each other when they operate. A private telephone network used within an enterprise. A United States telephone company that is one of Copyright ©2005 Technology Marketing Corporation. (2-packet) The short-term variation of transmission delay time for data packets that usually results from varying time delays in transmission due to different paths or routing processes used in a packet communication network. The PSAP usually receives the calling number identification information that can be used to determine the location of the caller.0. minimum committed bit rate (CBR) and other measurements that are used to ensure quality communications service. Public telephone networks within countries and regions are standard integrated systems of transmission and switching facilities. Some IP Telephones create a dialtone that allows the user to know that IP telephone service is available.IP Phone — An Internet protocol phone (IP phone) is a device (a telephone set) that converts audio signals and telephony control signals into Internet protocol packets. individual pulses appear to jitter or jump back and forth along the time axis. All rights reserved. PSAP — Public safety answering point. ISP — Internet service provider Jitter — (1-general) Jitter is a small. (3-IP Telephony) The variance of interpacket arrival times. cable or optical fiber. QoS measures may include service availability. The MOS is number that is determined by a panel of listeners who subjectively rate the quality of audio on various samples. Good quality telephone service (called "toll quality") has a MOS level of 4. These stand alone devices plug into (connect to) data networks (such as the Ethernet) and operate like traditional telephone sets. Page 12 . The rating level varies from 1 (bad) to 5 (excellent). signaling processors. An agency that receives and processes emergency calls.

home office UPS — A battery backup system designed to provide continuous power in the event of a commercial power failure or fluctuation. SIP is defined in RFC 2543. and gateways. SIP — SIP is an application layer protocol that uses text format messages to setup. the signal is first converted to a digital form. RBOCs are also known as the Baby Bells. The RBOCs were Ameritech. WAN — Wide-area network Copyright ©2005 Technology Marketing Corporation. If the telephone signal is in analog form (voice or fax). All rights reserved. ROI evaluates the impact of an investment on the telephone company's profitability or operational efficiency: dollars spent compared to benefits gained. SIP is a simplified version of the ITU H. Bell Atlantic.323 packet multimedia system.the seven telephone companies that were created as a result from the division of AT&T in 1983. A UPS system is particularly important for network servers. VoIP — A process of sending voice telephone signals over the Internet or other data network. ROI — Return on Investment is a financial measurement that compares the profit with the original investment. BellSouth. manage. Pacific Telesis. bridges. Southwestern Bell Corporation. Nynex. SMB — Small and medium businesses SOHO — Small office. Page 13 . and US West. and terminate multimedia communication sessions. Packet routing information is then added to the digital voice signal so it can be routed through the Internet or data network.