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.