Case:
People with diabetes face a continuous struggle to monitor andcontrol their blood glucose levels (BGLs). Allowing BGLs to falltoo low can result in hypoglycemia with the sufferer fainting,falling into a coma, or even dying. Allowing BGLs to go high hassevere long-term effects such as cardiovascular disease, nervedamage, and kidney damage or failure. High BGLs also cause damageto the blood vessels of the retina potentially leading toblindness. Improving BGL management has huge personal and communitybenefits in terms of long term health outcomes and costs.
Traditionally, diabetes sufferers monitor their BGLs severaltimes a day using a ‘finger pricker’ and blood strips inserted intoa portable BGL reader. However, this mechanism is painful, timeconsuming, inconvenient and expensive. The method provides anaccurate snapshot of blood glucose levels but provides noindication as to whether glucose levels are going up or down or howfast they are rising or falling.
Continuous Glucose Monitoring (CGM) is a huge advance ontraditional BGL monitoring methods. It allows diabetes sufferers togain insight into patterns and trends in glucose levels throughoutthe day and night. This allows them to monitor whether their BGL isrising or falling and to either take insulin or eat something asappropriate to maintain their BGLs in the desired range.
TotalCare were early movers in the field of CGM and offer a CGMsystem based on dedicated hardware and fixed wireless internetconnections.
The TotalCare CGM System consists of a very fine sensor placedunder the skin which measures glucose levels in cellularinterstitial fluid and records BGL readings every 5 minutes. Atransmitter is attached to the sensor and sends data wirelessly toa TotalCare Mobile Receiver carried by the user. Each night, theTotalCare Mobile Receiver connects to the user’s home wirelessnetwork and uploads the user’s daily BGL history to the TotalCareDiabetes Support System. The data is then available for nominatedhealth care providers to access, analyse, and provide advicefrom.
The field of Continuous Glucose is evolving rapidly, and othercompanies are offering more sophisticated products. In particular,systems which communicate with mobile devices via BlueTooth offergreat convenience, and a range of enhanced capabilities.
TotalCare have developed a new sensor with BlueTooth capabilityand sees a need to update their CGM system to communicate withmobile devices in order to maintain and grow their marketshare.
Part 1 – Non-Functional RequirementAnalysis
Conduct an NFR analysis for the given case study (provided tableis a starting point). Add to the checklist as appropriate for thecase study. Present the results in tabular form as shown:
|
NFR |
Question |
Benefits |
Costs |
Response |
Strategy |
Priority |
|
Privacy |
Is Privacy a concern? What sort of different access levels might be necessary? |
Protects the system from unintentional breaches of userdata. etc |
Makes the system harder to use, more expensive to build. Mayhave performance implications. |
Yes, privacy is a concern, we don’t want customers seeing othercustomers data, and we don’t want staff access other staffsrecords. |
Authentication and Authorisation |
1 |
Part 2 – Architectural Analysis
Present this in the form of a Software Architecture Notebookwith the following headings:
1. Goals and Philosophy – identify the keynon-functional requirements (e.g. security, reliability,availability, maintainability, compatibility, etc.) that the systemis attempting to satisfy.
2. Assumptions, Constraints and Dependencies -identify existing or proposed technology environments that willsupport or constrain the system. Identify external systems anddatabases with which the system will interact. Note: assumptions,constraints, and dependencies are pre-existing facts: they areobservations, rather than the result of a choice.
3. Architecturally Significant Requirements -identify key functional/non-functional requirements that haveimportant implications for the technical architecture of the systemand say what the implications are for those requirements.
4. Decisions and Justifications – Identify thedecisions made in determining the technical architecture and userinterface technology. Justify these against the key goals andphilosophies driving the architecture.
5. Architectural Mechanisms – Identify the keystrategies that you will implement to achieve the NFRs critical toyour application.
6. Architectural Style and TechnologicalFramework – state the overall architectural style that youhave chosen as the basis for your application and explain why itmeets the goals of the architecture. Then identify the technicalplatform with which you will implement your design and explain whythat platform is a suitable choice.
