Esloc Conversion Factors

Commercial

0%

0%

0%

0%

New

40%

20%

40%

100%

Reused

20%

5%

30%

55%

Automated

0%

0%

40%

40%

Tool input

30%

10%

10%

50%

The rationale for these conversion factors included many factors:

• Commercial off-the-shelf components do not result in any contribution to the ESLOC count. The integration of these components scales up with the amount of newly developed interfacing software.

• New software must be developed from scratch. It requires complete design, implementation, and test efforts, and has an ESLOC multiplier of 100% (one-for-one conversion).

• Reused components represent code that was previously developed for a different application but is applicable to the component with some modification. While there are many ways to assess the relative cost of reuse, and each instance is best handled individually, this conversion provides a simple rule of thumb as a default. In general, reused software requires 50% of the design effort, 25% of the implementation effort, and 75% of the test effort. Normalized across the 40/20/40 allocations of new software, this results in a total of 55%.

• Automated components usually require a separate source notation (the tool input format below) as input to a tool that then automatically produces the resulting SLOC. Because automated source code becomes part of the end product, it needs to be fully tested. However, the design and implementation effort is set to zero. If the tool that automates the source code production must be developed, its SLOC count should be included in the new category. The resulting conversion factor is a 40% SLOC-to-ESLOC ratio.

• Tool input can take on many diverse forms. CCPDS-R had input files for the architecture definition (a long but straightforward table of names, attributes, and relationships), display definitions (display object types, locations, and attributes), and message validation. These higher level abstraction formats were converted using 75% of the design effort (simple, high-level notations), 50% of the implementation effort (repetitive, high-level syntax and semantics), and 25% of the test effort (which focused on the generated code, not this code). The resulting conversion factor is a 50% SLOC-to-ESLOC ratio.

All in all, the development of a few code production tools reduced the total ESLOC of the Common Subsystem by 78,000 lines, as summarized in Table D-12. ESLOC was analyzed solely to ensure that the overall staffing and budget allocations, negotiated with each CSCI lead, were relatively fair. These ESLOC estimates were input to cost modeling analyses that incorporated the relative complexity of each CSCI and the other COCOMO effort adjustment factors.

Table D-12. Common Subsystem CSC1 sizes in ESLOC
Project Management Made Easy

Project Management Made Easy

What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.

Get My Free Ebook


Post a comment