Estimating Maintenance Cost for Web Applications

Abstract

(ProQuest: ... denotes formulae omitted.)1 Research Premises and HypothesisMaintenance costs have a consistent weight in the total costs generated by an application during its entire lifecycle. Previously conducted research and studies that focus on software maintenance support this claim. In [2], the 60/60 rule of software is depicted. The rule claims that maintenance accounts for 60% of the total costs generated by a software in its entire lifecycle. Enhancement or perfective [3] maintenance tasks account for 60% of all the costs generated by maintenance [2], whereas error correction or corrective [3] maintenance tasks account only for 17% of total maintenance costs [2]. In [4] it's stated that software applications evolve over time to meet the changing needs which leads to maintenance generating 67% of the applications total lifecycle costs. In [5] it is argued that maintenance typically accounts for 75% or more of the total software workload. Other relevant research place maintenance costs at 90% [6], 75% [7], 90% [8] or at 60% to 70% [9] of the overall application's lifecycle cost. It is therefore of paramount importance to accurately estimate maintenance cost before implementing a software project in order to better comprehend the total costs associated with developing and owing a software application. Better understanding maintenance costs will provide valuable information regarding resource planning and the appropriate time to decommission the application.The cost of maintenance is directly determined by the number of people involved in the maintenance process and the number of hours each person invests in the maintenance tasks. Thus in order to estimate maintenance cost one needs to estimate the effort invested in the maintenance process. The maintenance effort is expressed in man-hours which entails the number of ours dedicated by the maintenance team to implementing maintenance tasks. Maintenance in web applications has two main components: content maintenance and technical maintenance.Content maintenance requires performing tasks of a non-technical nature like updating product inventory and information, adding news or articles, managing blog posts, updating contact or brand and visual identity information and moderating user comments or messages. Content maintenance team staffing and therefore content maintenance effort is determined by the web application's size [1].According to [1] and as presented in Table 1, content maintenance cost is determined by the number of hours required to keep the web application up to date in terms of content. The larger the application the more hours need to be invested in keeping it up to date in terms of content. The more content changes in an application the more technical maintenance tasks are generated. Technical maintenance tasks are generated because content managers spot bugs or request new functionality to help keep the content up to date. Therefore, content update frequency is a factor that impacts maintenance effort and cost.Technical maintenance requires adding new functionality, performing regular back-ups, monitoring website outages, checking IP reputation, checking DNS configuration, test website speed, check for broken links, perform software updates if third party software was used when developing the web application, monitor traffic statistics and review search engine indexing.According to [1] and as presented in Table 2, technical team stuffing is determined by the level of complexity built into the web application. Thus, a Basic web application which is characterized by static content build mainly using front-end technologies like HTML, CSS and JavaScript will require no more than 1 person to perform maintenance tasks. A Dynamic web application which stores its content in a database and has functionality which is powered by PHP, Java, ASP.NET, Python, Ruby or any other high-level programming language will require 1 to 2 persons to perform maintenance tasks. …