Abstract
A network is a line coverage that is topology based and consists of connected linear features. A communication network, in its simplest form, is a set of equipment and facilities that provides as service: the transfer of information between the users located at various geographical points. Internet or inter network is no exception to this, which involves the interconnection of multiple networks into a single large area network. Today GIS is used extensively to plan, build and operate communication networks and associated services.
GIS can handle complex network problems, such as road network analysis. There are, of course, other types of network analysis, involving stream networks. For example, GIS could be used to model the flow of water through a river system, to plan a flood warning system.
Shortest path analysis is based on a network with the objective of finding the path with the minimum cumulative cost in either time or distance between points on the network. Familiar networks include road system, railways, public transit, streams and shorelines etc... Another network which is analogous to the above networks is the WAN using cables. However the cable networks are different from the networks mentioned above. Some of the salient features of these networks are
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Need of detailed information of not only topography but also interior of the buildings.
- Cable laying is normally performed at the different elevations. Hence the need of integration and information of details at different elevations is necessary.
- More number of alternatives as compared to the other networks.
- More number of constraints
- Maximum length between the switch to a user is 90m.
- Fiber cables should be mainly underground
- Trenching involves labour cost , so trenching should be minimized
- Cost directly proportional to length of the cable.
- More number of components are involved; switch size, cable size etc…
Due to the aforesaid factors the analysis of cable networks is difficult and need spatial and non spatial information. Hence GIS (Geographical Information System) which is capable of handling both types of information is most suitable tool for such problems. A Geographic Information System (GIS) is a computer system for capturing, storing, querying, analyzing and displaying geographic data.
What distinguishes GIS from other forms of information systems, such as databases and spreadsheets, is that GIS deals with spatial information. GIS has the capability to relate layers of data for the same points in space, combining, analyzing and, finally, mapping out the results. Spatial information uses location, within a coordinate system, as its reference base. The most common representation of spatial information is a map on which the location of any point could be given using latitude and longitude, or local grid references.
Some applications of GIS are obvious, for example water supply companies use GIS as a spatial database of pipes and manholes; local governments can use GIS to manage and update property boundaries, emergency operations and environmental resources.
Till now the application of GIS is limited to such networks. The present paper aims to extend the use of GIS to cable networks integrated with drawing tools such as AUTOCAD.
The paper presents a situation of planning a Wide Area Network (WAN) in technical education campus of Birla Institute of Technology & Science (BITS), Pilani, Rajasthan, INDIA. The aim of the project is to provide net access to around 3500 students and 600 staff’s quarters.
The project aims at providing net access to all rooms of the hostels and staff quarters by WAN. The cables used are the outdoor fiber and indoor copper cable. The basic plan is to take the outdoor fiber from a core (master) switch to a distribution switch from where the access switch can cater to the rooms using indoor copper cables .The number of distribution, access switch varies depending on the need. The project aims to find an optimum path for both the fiber and indoor copper cables and hence reduce the cost
The digital map of the campus is taken and the basic operations such as
geo referencing, digitizing are carried out. The images of the hostels, staff quarters and the interior view of the hostels are created with AUTOCAD RELEASE14 and AUTOCAD 2000 and then imported into ARC VIEW for analysis.
Network analyst and shortest path analysis are used to find the optimum path for the cables so as to reduce the cost. Various constraints are taken care when using cables and few are mentioned before.
We have used ARC VIEW GIS version 3.1 for the whole analysis and AUTOCAD RELEASE14 and AUTOCAD 2000 for creating images of the campus and hostels.
The results indicate a saving of 10% in length of cables with respect to the prior estimations without using GIS. This will not only help in reducing cost but also will help in proper planning of inventory control and in monitoring the contractor’s job.