A potential solution to this underlying weakness of DAS is the Community Fiber-Optic Network (CFN) projects that are growing in popularity. Whether being built by an RBOC like Verizon or SBC, or by an underserved community itself, these networks entail a fiber deployment of a density never before seen. A very dense fiber network with many nodes is the perfect backbone for an outdoor DAS. By renting part of someone else’s network rather than building his own, a potential DAS builder has eliminated the major economic stumbling block for the project.

The gains of a DAS/CFN partnership are not one-sided. The economic stumbling block faced by a potential CFN builder is the uncertainty of relying on many small churn-prone customers as the primary revenue source. By signing up a DAS as a customer, the CFN has gained the churn-proof equivalent of hundreds of residential customers. Now, the CFN has a far better chance of making or beating time to payback projections.

This basic concept of a CFN leasing dark fiber for use in a DAS can be taken a step farther by incorporating the concept of Neutral Hosting into the CFN. In this model, the DAS becomes an integral part of the CFN rather than just an adjunct to it. Not only does the CFN operator provide client carriers with equipment to transform their traditional network into a DAS, or build a new network with a DAS topology, but also makes available hotel and remote antenna locations. Ideally these locations are part of the infrastructure used to create the CFN or are already owned by the CFN operator. A further evolution of this concept uses software-defined base-stations to allow the Neutral Host to offer a completely turnkey solution, using generic equipment at the hotels, to the carriers. When considering how many potential clients a Neutral Host DAS could have, remember that this solution is applicable to any wireless carrier, not just mobile telephony companies.

While DAS and CFN is a match made in heaven, the two must still find a way to come together. The simplest cases involve wireless carriers soliciting CFN operators for fiber to use in constructing their own DAS or the CFN operators soliciting carriers to rent their fiber for that same reason. The case of the CFN operator becoming a Neutral Host is more complicated, but also a much larger business opportunity. Then, there is the case of a third-party renting fiber to, become in turn, a Neutral Host. In any case, making the deal happen requires the right expertise – expertise that neither a wireless carrier nor a CFN operator is likely to possess. Clearly, finding the right partner to aid in the identification and evaluation of potential opportunities is key. Stratum Broadband specializes in finding the right solution for each client’s needs.

]]> Wireless Solutions http://www.stratumbroadband.com/index.php?itemid=7 Fri, 7 Jul 2006 14:43:40 -0400 http://www.stratumbroadband.com/index.php?itemid=8 Sample Consulting Engagement The following scenario is based on a composite of actual Stratum Broadband engagements.

A city or town is interested in implementing a broadband wireless data network for various city personnel, including first responders. The committee knows what they want the network to do and who they want it to serve, but has no idea how to begin building it. They must design, build, and deploy the network, select equipment vendors and wireless carriers, and determine the software platforms needed. They need to know how to pay for the network. They need help!The city engages Stratum Broadband to provide the technical expertise to get the project done. Stratum Broadband assesses the requirements and defines the project’s scope and feasibility. Their objectives are to design the appropriate high-level architecture for the wireless network, present a general budget for building and maintaining the network, and provide an implementation plan for deploying the network. Stratum Broadband employs a tested methodology to successfully get through all the steps involved in implementing the city’s new wireless network.

Stratum Broadband begins with a kickoff meeting for key stakeholders, such as the wireless project committee, the city CIO, and representatives of the police, fire, and EMS departments. The meeting creates an atmosphere of participation and buy-in to the process by:

• Clarifying the scope and objectives for the wireless network project.
• Describing the activities for the project and listing the overall schedule of events.
• Outlining the interview process and defining the data types that need to be gathered – either by survey or by copies of relevant engineering drawings, documents, or listings.
• Clarifying the dependencies on the stakeholders.

After the kickoff meeting, the Stratum Broadband team conducts interviews and surveys to gather all necessary information to design and build the best network solution. To work out any gaps and misunderstandings, the team makes quick calls or sends email requests for clarifications or additional information. Now, Stratum Broadband is ready to answer the city’s questions.

The team determines the city has the necessary infrastructure to implement either a WiFi Mesh or a WiMax network topology. The city must make a decision on how to proceed. Research indicates that the nearby university already has the wireless licenses necessary for an efficient WiMax implementation. However, partnering with the university would add complexity to the project. Research also indicates that a WiFi Mesh would be significantly less expensive to build (although both topologies have about the same net present value over five years). Since supporting first responders is crucial to the city, they decide against unlicensed WiFi and in favor of a partnership with the university to use its licensed WiMax.

With the decision in place, Stratum Broadband returns to the university to learn more about their requirements in the partnership. They want to provide intranet access to students that live off-campus. After factoring in the equipment required to support the campus users, it appears that the proposed system will be able to offer ISP service to a large portion of the city’s residents. Stratum Broadband can now create financial models based on the city wholesaling service to a local ISP.

Stratum Broadband presents their findings to the city in a written document and as a presentation to the wireless committee and other interested parties. The presentation explains why partnership with the university is the city's best choice, presents the high-level architecture for the WiMax network, and defines the budget for deploying it. In addition, the presentation shows that some additional components can be added to the system to support disaster recovery in the face of a natural or manmade catastrophe. The additional cost of such components is explained. Stratum Broadband also describes how offering wholesale services to an ISP can be incorporated into the implementation plan. The team recommends how to provide proper quality service to first responders while supporting wholesale operations and how to incorporate disaster readiness upgrades into the implementation plan. The presentation also outlines a schedule for completing the network buildout and describes the next steps in the process.

With the architecture and budget in place, Stratum Broadband is ready for the next steps in implementing the city’s new wireless network – interviewing the interested equipment vendors and carriers, building a pilot network to demonstrate the required capabilities, and completing the construction and implementation phases of the actual network.

]]> Wireless Solutions http://www.stratumbroadband.com/index.php?itemid=8 Wed, 7 Jun 2006 14:48:00 -0400 http://www.stratumbroadband.com/index.php?itemid=9 Sample Implementation Engagement The following scenario is based on a composite of actual Stratum Broadband engagements.

State University is interested in providing ubiquitous wireless data access the campus. They would also like to improve the availability of commercial wireless services in some of their buildings. They know exactly what capabilities they'll need and how many people they want to eventually have on the network, but don't know what vendors and platforms to use or what architecture to implement. They are also unsure about how to go about improving commercial wireless services. The State U IT staff is too busy to implement new networks, so they are looking for a turn-key solution. State U brings in Stratum Broadband for a consulting engagement. The objectives are to design and implement a campus-wide wireless extension to the existing network and to work with carriers to improve the availability of commercial wireless services.Stratum Broadband begins with a kickoff meeting for key stakeholders (CIO and members of IT and physical plant) to clarify the scope and objectives for the project. The kickoff describes the activities for the project and the overall schedule of events. It outlines the interview process and defines the data types that need to be gathered – either by survey or by copies of relevant engineering drawings, documents, or listings. It clarifies the dependencies on the State U stakeholders and, in general, creates an atmosphere of participation and buy-in to the process. The kickoff meeting also allows some immediate tuning of the process and the sensitivity awareness needed for smooth operation of the project.

After the kickoff meeting, Stratum Broadband researches all necessary information through a series of interviews and surveys. To work out the gaps and misunderstandings, the team makes quick calls or sends email requests for clarifications or additional information.

Now, Stratum Broadband is ready to put together the answers to the State University's questions. From their research, Stratum Broadband has learned that State U has an excellent wired Ethernet network. Therefore, the primary challenge for deploying the desired WiFi network will be proper design of the radio network. Care must be taken in this design to avoid interference¹ so the network can support high user densities. The wired network, which uses fiber optics in many cases, has a good deal of dark fibers. These dark fibers could form the backbone of a distributed antennae system (DAS) that would allow carriers to improve commercial wireless coverage in a very cost-effective manner. Although DAS is a highly effective technique, it is at odds with the cookie cutter technique most carriers use when expanding their networks. Stratum Broadband must determine if the benefits to commercial wireless users on campus are worth convincing multiple carriers to join a DAS. The ad-hoc improvements gained by allowing carriers to place some additional base-stations on campus might be sufficient.

Stratum Broadband returns to State U to learn more about their requirements. Although it is easy to rent some rooftops to carriers, State U is more concerned with getting better use out of their own wireless subscriptions and in solving student complaints about inadequate service in many buildings. They are also concerned with the aesthetic impact of deploying ad-hoc base-stations on campus. To facilitate the decision, Stratum Broadband creates financial models based on varying rents and carrier capital contributions to finance the DAS.

Stratum Broadband presents their findings to State U both as written documents and as a presentation to the wireless committee and other interested parties. Stratum Broadband outlines the best options for deploying a DAS and the various scenarios of carrier involvement. The presentation includes a high-level architecture, implementation plan, and budget for both a WiFi and a DAS deployment.

A few weeks later, State U authorizes Stratum Broadband to proceed with implementing the network. Installing the WiFi system is fairly straightforward and proceeds quickly, but negotiations with wireless carriers are cumbersome. After many conference calls and visits to the campus by engineering staff-members of all carriers, two carriers commit to joining the DAS immediately. A third carrier also commits, but will not be able to join until the next fiscal year for budgetary reasons. Financial models show that even two carriers are sufficient to give DAS deployment a positive five-year net present value, so work commences. In the mean time, the WiFi system is completely installed and commissioned. Commissioning results indicate performance in excess of requirements.

University publications report enthusiastically on the new wireless network and forthcoming enhanced commercial wireless service. Soon the campus is abuzz with news that cell phones finally work in the freshman dorms and other diverse locations. A few hundred pager accounts are retired now that Maintenance can rely on cell phones alone. A few months later, the third carrier is ready to connect to the system in a simple process with no disruption to the existing system. State U receives much publicity about their world-class wireless campus, including an article in the Wall Street Journal.

1. With WiFi, true signal-to-signal interference is usually not a major concern. Interference, in this case, is the increase in latency caused by the WiFi contention system. The effect is similar to the packet retransmission necessitated by high bit error rates occurring due to true signal-to-signal interference. Just like signal-to-signal interference, contention issues are often the result of poor channel reuse.