SIP For Enterprise:White Paperand What It Can Do For YouWritten by Steven Shepard, President, Shepard Communications Group, LLCxo.com
SIP for the EnterpriseAnd What Can it Do For YouAuthored by: Table of ContentsSteve Shepard, PresidentShepard Communications Group, LLC SIP for the Enterprise — How Did We Get Here? 1Commissioned by XO Communications What Exactly is SIP? 1 The Combination for Success — The New Age is Here 2 What is Enterprise SIP (ESIP)? 2 Key Advantages and Business Benefits of Enterprise SIP 5 Advantages 5 Key Business Benefits 5 Options When You Have a Private Network Already in Place 6 Added Business Continuity 6 Is an Enterprise SIP Solution Right for You? 6 Summary 72 Solutions you want. Support you need.
XO Communications SIP for the Enterprise — How Did We Get Here? Over the last ten years, telephony as a service has evolved. How it works, what it does, and how it is used by both consumers and businesses has changed. The telephone network was originally designed to transport voice calls, something it did well. Over time, the mar- ket demanded much more. In response, and thanks to the signaling network known as SS7, the Public Switched Telephone Network (PSTN) was enhanced to deliver a broader array of supplementary services. Enter the debut of the Private Branch Exchange (PBX) which put more control into the hands of the enterprise’s technical support personnel. The Internet and Internet Protocol (IP) became accepted and pervasive. With the introduction of Voice over IP (VoIP), the cost and complexity of operating the network declined (a boon to the service provider) and the range and richness“When SIP is deployed in the of services available to the customer increased.network, telephony becomes a The diversity of the telecommunications services demand profile forced a redefinition of theWeb application. It integrates network architecture by which services are delivered. Instead of delivering services from deepseamlessly with other Internet within the core of the network, it became more efficient to move the point of delivery out to the edge, particularly for enterprise companies. But because SS7 was designed as a core-services, and the convergence based protocol, it could not meet the new demands being placed on the network. A new solu-of voice and data including tion was required; that solution is the Session Initiation Protocol, commonly known as SIP.video, audio and image transferbecomes real.” What Exactly is SIP? Like SS7, SIP is a signaling protocol designed to set up communication sessions in a net- work, but this time, in an IP network. These sessions include everything from a simple phone call to a multi-location, multimedia conference. Because SIP was designed to support a wide array of service types, new and innovative capabilities become possible such as Web page click-to-call, Instant Messaging with incor- porated buddy list access, and IP PBX support. SIP is a simple, command-response protocol that is operationally similar to the protocol that governs the functionality of the Web: HTTP. When SIP is deployed in the network, telephony becomes a Web application. It integrates seamlessly with other Internet services, and the convergence of voice and data including video, audio and image transfer becomes real. SIP has become the basis for the next-generation network. It undoubtedly will be deployed by all service providers, from traditional wireline players, to mobile providers, to cable compa- nies offering VoIP, to ISPs. SIP facilitates the delivery of everything from traditional voice services to a host of capabilities such as convergence, IMS, femtocell deployment, online gaming, voice and video conferencing, among many others. And SIP is an internationally recognized standard (a subset of the IP protocol suite), meaning that interoperability is a non-issue. 3
SIP for the Enterprise The Combination for Success — The New Age is Here The flexibility and richness of IP is combined with the highly customizable nature of the PBX, creating the IP-PBX. The result is extraordinary. Now we have technology emerging with the power to redefine the way businesses communicate. The flexibility and richness of IP, the power and control of the PBX, and the breadth that SIP brings to the table shine a bright light for Enterprise businesses. Enterprise SIP is the optimal result. What is Enterprise SIP (ESIP)? Network gurus for multi-location businesses know the process of interconnecting the“In addition to hosted unified branches to facilitate effective site-to-site communications is complicated, expensive andcommunications, SIP trunking time-consuming.and its offspring like XO In many cases companies rely on several service providers to provide full connectivity acrossEnterprise SIP will be the their entire enterprise geography. As service demands change, whentransport with which unified more bandwidth is required to a particular site, for example – the modifications required tocommunications is carried.” make that happen can be costly in terms of both money and time. To further complicate matters, many multi-location businesses have grown through acquisi- tions and mergers, resulting in an inherited mix of on-premise equipment types and local~ Rebecca Swensen, IDC services. This collage of premise configurations makes seamless site to site communications and a unified customer experience next to impossible. The solution? Enterprise SIP. Enterprise SIP is a powerful new solution designed for multi-location businesses that enables the business to serve its distributed branches with telephone service through one or a hand- ful of centralized PBXs. It can provide centralized trunking and eliminate the need for PRIs or business lines at each location. Enterprise SIP also enables the business to carry all voice and data over its private Wide Area Network (WAN), resulting in more efficient use of the network. It does all of this with built-in load-sharing capabilities to provide bandwidth where and when it’s needed to fully satisfy demand. Some SIP for the Enterprise services also provide bursting capabilities to accommodate seasonal demands or catastrophic network events.4 Solutions you want. Support you need.
XO Communications Before Enterprise SIP, it has been common for a multi-location business to have a telecom infrastructure similar to the network illustrated in Figure 1. Because of the company’s many locations, it was often necessary to engage multiple service providers to ensure connectivity between each location’s PBX and the Public Switched Telephone Network (PSTN). In most cases, these connections were either ISDN PRI connections or IP trunks.Figure 1: Typical SIPConfiguration before anEnterprise SIP deployment. Branch 2 Provider 2 Branch 4 Branch 1 Branch 3 Provider ILEC Provider 1 Provider 3 4 #1 PRI DIA #1 + + + + + Provider Headquarters 5 Provider Provider 8 7 DIA #2 Provider 6 ILEC #2 + PRI + + + + Branch 5 Regional Ofﬁce Branch 6 Branch 8 Branch 7 5
SIP for the Enterprise With the arrival of Enterprise SIP, things change. Instead of connections to each branch and through multiple carriers, it is now possible to provide an increased level of connectivity, with added redundancy – by consolidating those connections through a small number of locations and with a single carrier, while saving costs and streamlining telecom operations, as shown in Figure 2.Figure 2: Simplifiedconnectivity following theintroduction of an EnterpriseSIP deployment. MPLS IP-VPN Network Branch 2 Branch 1 Branch 3 Branch 4 Headquarters Failover XO Communications Branch 5 Regional Ofﬁce Branch 8 Branch 6 Branch 76 Solutions you want. Support you need.
XO Communications Key Advantages and Business Benefits of Enterprise SIP Not only does Enterprise SIP eliminate the need to buy and manage lines for each and every location, it also streamlines the operation of the telecommunications infrastructure using a centralized PBX, rather than managing multiple, disparate systems at the premise. Key Advantages: • Lower operating costs through centralizing communications facilities • Reduce location equipment needs and connectivity requirements • Enable flexible redundancy • Allow bursting: capacity can be shared seamlessly and fluidly across the entire enterprise when needed“Not only does Enterprise • Use existing WAN for voice communications, resulting in more dynamic and efficient network resource utilizationSIP eliminate the need tobuy and manage lines for Business Benefitseach and every location, italso streamlines the operation A primary and most important benefit that comes from Enterprise SIP is the degree of control that a customer enjoys, and the flexibility that it makes possible.of the telecommunicationsinfrastructure using a centralized 1. Consolidating voice and data over a single, converged IP network greatly reduces the cost andPBX, rather than managing complexity of administration and management. Fundamentally, costs are reduced as the capacity required for voice and data sessions is shared across the entire network.multiple, disparate systems at thepremise.” 2. Centralizing the PBX equipment in one or a few sites results in capital savings, greater control over site to site calling, and a unified customer experience. The headache of trying to control communications across a myriad of premise configurations is gone, leaving only a router and phones at the premise. 3. Enterprise SIP allows for the consolidation of local and long distance inbound and outbound call- ing across the entire enterprise, regardless of the calling and called parties’ physical locations. 4. Enterprise SIP makes bandwidth management easy. By allowing for instantaneously available bandwidth on a demand basis, inbound and outbound calls always have adequate resources avail- able to them. 5. And finally, Enterprise SIP allows for traffic prioritization: Voice can always be assigned the highest priority among the various traffic types using the connection, thus guaranteeing assured quality- of-service (QoS). Of course these provide just a taste of benefits apparent to a business with Enterprise SIP. 7
SIP for the Enterprise Options When You Have a Private Network Already in Place In many cases, companies have already invested in their own private networks, typically MPLS IP VPNs, but sometimes Private Lines or even Dedicated Internet Access. Enterprise SIP allows a company to take advantage of that investment by overlaying voice calling on the existing network, further stretching the investment made. For example, XO even allows SIP to be used with another carriers data network. Those same companies may have also invested in VoIP as part of their evolution and now Enterprise SIP allows them to take advantage of those investments through seamless integration of those assets into the mix. And because the enterprise most likely has its own highly-skilled IT department with deep knowledge of network and system performance, discrete control of network availability and service performance can be conducted in-house. This results in differentiable quality-of-service and assured business-class call quality across the enterprise. Added Business Continuity Network Survivability is critical to most companies, and because Enterprise SIP relies on IP, a broad array of business continuity options become possible. These options are much more difficult – and expensive – to deliver over the legacy switched network. If one route becomes unusable or excessively congested, Enterprise SIP re-routes the connection across an alternate route, with no change in quality of service. Finally, because the service can be delivered by a single provider, far more flexible pricing is available due to the consolidation of resources. The power accrues to the customer. It doesn’t get much better than that. Is an Enterprise SIP Solution Right for You? So how do you know whether Enterprise SIP is an optimal solution for your business? Ask yourself these questions: 1. Do you have more than five operating locations? 2. Does the geographically-dispersed nature of your company have you using more than one carrier for your telecommunications needs? 3. Do you have inadequate leverage with your carriers? 4. Are you spending too much for long-distance connections and voice calling? 5. Are you spending too much capital on media gateways and PBX network connections? 6. Are you uncomfortable with the level of survivability available in your network? 7. Could you get more value out of your IP-PBX installation? If you answered ‘yes’ to one or more of these questions, then your business may be a viable candidate for an Enterprise SIP solution. The cost savings, added functionality and survivability alone make it a technology progression that is worth serious consideration.8 Solutions you want. Support you need.