GIS data is the merger of geographical details and collected information. Geographical detail consists of co-ordinates and geometries of the elements, such as points (e.g. address locations), lines (e.g. streets) or polygons (e.g. city borders). Collected information includes names and details about the element, e.g. street name, address, number of housing units in the address, residential or commercial, etc.
Web maps services use GIS information about the address location, streets information and traffic information to give you different routing options with the expected time associated with those routes. In a similar way automated network planning and design tools use address information, street data, pole locations and other geographic information to route the cables and design the network with the cost associated with that network design.
Automation tools are quickly replacing the traditional methods of planning and designing networks by hand as they are far more efficient. GIS data is a crucial requirement for these tools, therefore users need to know how to gather this data effectively.
We have compiled a list of different GIS data sources and techniques to acquire this data. Every source or technique has its strengths and limitations, so it is important to understand their characteristics, costs, and benefits before using them.
Open source data is by definition data that can be used for free. These projects typically are an initiative of a community of volunteers, so the quality cannot be guaranteed. However, in general if there is a strong community working on the project, the quality can be very high.
Data sources we frequently use:
|Use of data is absolutely free.||Data can be inaccurate or information might be missing so a bit of user editing might be required.|
|Available data is constantly being updated by 2 million members, who use GPS tools, satellite photographs, and their own knowledge of the area. Community members verify new entries and correct mistakes as well.||Data is not available for all communities and varies significantly by nation. Availability and quality of the data depends on how active the local community is.|
Local government (cities, counties, etc.) bodies collect and provide data. But data is usually not readily available on the internet and coverage can vary greatly. This changes rapidly as more and more government bodies are making data available online. Contact local municipalities and development authorities or check their website for the available data.
|Available data is accurate and detailed.||Different government agencies organise their structure and data in different ways, which means the data format can vary from place to place. The available data might not be in your preferred format. This requires some conversion work.|
|One strong suit of getting information from government agencies is that most info is in the public domain, and can be used for free. Occasionally, a small transfer cost is charged.||As states and cities vary so greatly in their systems of organisation, it might take some time to discover which agency holds the information you want. This means that finding information can be time-consuming and could involve making phone calls, writing letters, asking questions, and visiting the agencies in person.|
Paid GIS providers
There are many private sources of GIS information, with commercial mapmaking firms among the largest providers. Nevertheless, there are plenty of other firms that have also supplied this information for years now. These providers can also help you to find publicly available data or convert existing data as per user needs.
|Detailed demographic and socioeconomic information usually available.||This information can be expensive to purchase. It can vary depending on the technology they use to gather the data: data collection, desktop survey or street survey.|
|Highly accurate because the data is usually checked and corrected as it is repackaged. These datasets are built to the user’s specifications and preferred format.||This can be a time-consuming effort as the data is not always readily available.|
Mobile mapping is when you collect geospatial data from a mobile vehicle, typically fitted with a range of photographic, radar, LiDAR or any number of remote sensing systems. The primary output from such systems include GIS data, digital maps, and georeferenced images and video. This technique you can use yourself, or hire through data providers in your area.
|This process provides a rich dataset with high data density for close range acquisition.||Acquiring data through this method can be expensive.|
|The data is extremely accurate, up to a few millimeters depending on the hardware used.||This is a strictly line-of-sight technology. In general terms, if you can not visually see the feature from the acquisition platform, it will not be processed e.g. if you want to count the number of doorbells to estimate the home count, they need to be visible from the street.|
One of the great leaps forward due to technology is the advancement of field survey tools. Not so long ago, a field surveyor would use sheets of paper to fill out pre-defined questionnaires and use an expensive GPS device to geo-locate his location or write it down. These days, the surveyor uses a tablet or a smartphone to process his information.
|Full control over which data is captured.||It is time-consuming to collect data as you need to walk every single street.|
|You are sure the data is up-to-date.||It is possible to occasionally miss information. This might only be discovered at a later stage.|
There are many ways to acquire GIS data for your fiber network deployment project. Each have their pros and cons, depending on different variables. It often makes sense to combine the listed sources. For example, in the early planning phase free data from open sources can be enough to make decisions like whether or where to rollout. Once you made these decisions, you can opt for paid sources to obtain more details and to verify the information in the field.