By Aiden Gallagher & Peter Reeves
Introduction
Why do we care?
Definitions
Pattern
Blueprint
Templates
Standards
Reference Architectures
Integration Example
Standardisation
Reusability
Familiarity
Future Proofing for the whole Organisation
Limitations
Complexity
Blocker to change
Stifling Innovation
Conclusion
*Disclaimer: These are our own definitions and might not map to your specific organisation. And, of course, these are our own opinions, and not necessarily those of our employer
Introduction
For the last few weeks, Peter and I have been talking about Integration Patterns, blueprints and architectures to try and boil down a common definition which we can use when talking about these concepts.
We found that halfway through a conversation we would start merging elements and classifying the same integration item as different things.
To remedy this, we decided to write down the definitions as a reference point that we could refer back to. In this blog post you will be able to see these definitions, and when we talk about Patterns, Blueprints, Templates, Standards and Reference Architectures you will know what we mean too.
Why do we care?
Before we share the definitions, it’s important to know why we care about the words themselves. We want to be sure that when we are discussing concepts that we are all referring to the same things and in the same way, related to how artefacts fit into the wider organizational picture and the correct governance procedures when designing systems.
Definitions
Below you will find our definitions and with them an example of how these are applied outside of the computing world. In this example, we will apply them to a housing project and “dwellings”.
Pattern
Definition – A pattern is a refined repeatable concept which is a solution to a common problem.
Example – Given the common problem of a human needing a place to live; have a roof over our heads, running water, sanitation, heat and the ability to cook, a pattern standardises the way we build a ‘dwelling’ that acts as a solution to these problems.
Blueprint
Definition – A blueprint is a detailed design for how to implement a pattern using a certain technology.
Example - A blueprint of the dwelling pattern could be a terraced house which provides dwellings against a limited land space. It could also be a bungalow which provides accessible dwellings for those who cannot use an upstairs.
Templates
Definition – A template is an implementation of a blueprint with further details on the specifications for items of that type. It might be followed exactly, or it might be altered to fit the need of the circumstance.
Example – A terraced house in Darlington was previously built with certain specification. The designer wants to provide more garden space as such they can tweak the template of a terraced house during design. But the template largely remains the same.
Standards
Definition – Standards are an approach, design or method that is applied across all interconnected systems and applications to ensure consistency of approach, and this benefits support, testing, and development.
Example – The plug sockets in all houses are the same size, as that meets the requirements for the majority of household appliances. This means all devices are interchangeable, which in turn means less customisation during build and hence is cheaper to build and more convenient for the end users.
Reference Architectures
Definition – A reference Architecture is a set of documents or information that describe a topology or system that can be used for common and related patterns. The information, if followed, will provide commonality across deployed templates and blueprints.
Example - A large plot of land is bought for building development requiring sewage, electricity, water, gas, and road network. A reference architecture describes how this infrastructure can be setup to accommodate different home styles (patterns) the instructions for building each home (blueprint), and potentially any customisations to the blueprint to fit other requirements (templates, and templated usage). Throughout the whole build process the same style of roofs, doors and windows are purchased (standards).
Integration Example
In the integration world we might apply the above definitions to the following use case.
A hybrid-cloud deployment strategy has been documented which shows how availability, disaster recovery, networking, and deployments of servers, and various business functions might be achieved in a reference architecture for that system.
The cloud deployment has a number of topologies (or building blocks for topologies). These are used as necessary to build integration patterns (e.g. request-reply which needs to solve some high-level problems like: access to a database, transactionality, reliability etc.)
Having selected the reference architecture which will support specific patterns, a blueprints to implement desired patterns using those cloud offerings can be written by the organisation – this could form a high-level design of how the new system will look like, this is further refined and customised in the low-level design.
Looking at a Hybrid Cloud implementation, there are some orchestrated deployments packaged as part of a cloud offerings to solve specific business needs, which is in itself like an off-the-shelf blueprint combined.
To build the system, a series of templates are used for each cloud product with necessary minor tweaks that meet small nuances of the pattern and blueprint requirements. Throughout all these processes the organization’s standards are used to ensure naming conventions are the same, disaster recovery can be performed by any of the support teams, that port mappings follow the same style for easier communication with the network teams, and any other core business procedures are followed.
The end result is a system that was built quickly, in a reusable, extensible, and familiar way and that is now supportable by the wider organization.
Benefits
By using Patterns, Blueprints, Templates, Standards and Reference Architectures there are obvious tangible benefits:
Standardisation
· Less complexity when implementing solutions as everything is known.
· Cost reduction of multiple teams solving the same problems repeatedly (why reinvent the wheel?)
Reusability
· Once the patterns, blueprints etc. have been shaped and refined, it becomes easier to reuse them than to start the building process from scratch- saving time and energy exponentially.
· They are easy to use.
· They are easy to deploy.
· They are easy to support.
Familiarity
· There is less project-specific knowledge required when people switch roles as the core patterns (and blueprints) are the same.
· Individuals are able to get the 'gist' of what is happening in a new project- even for customised docs, build etc- because everything looks and feels the same and was built with the same principles, even if the low-level implementation is slightly different.
· This familiarity makes it easier and quicker to fix, debug and test new projects.
· This leads to a reduction in dependencies on individual resources.
Future Proofing for the whole Organisation
· Improving the pattern by one team improves for all.
· The whole organisation is carried into modern practices together because of the usage of patterns, blueprints etc.
Limitations
There are some limitations to the usage of Patterns, Blueprints, Templates, Standards and Reference Architectures which tie closely together:
Complexity
· Sometimes complexity is required, maybe because something has never been done before, or there are new nuances such as security regulations that make a solution difficult to implement using existing patterns.
· Trying to fit the patterns into these use cases might cause more harm than good e.g. over-engineering, barrier to release time, tendency towards “You aren’t going to need it” (YAGNI) behaviours and a bloated system.
Blocker to change
· It can be hard to change a pattern because it’s a known entity which people are familiar with. The pattern then becomes a tool to block improvements.
· It can be hard to get change because the benefits of a new system might not be understood by the wider organisation who must accept these changes.
· Patterns become tied to governance process. This can undermine the governance process which can be deemed as ‘red tape’.
Stifling Innovation
· Working only to the pattern can stifle the creativity which comes naturally to a lot of people in an organisation. This means that the pattern and its prescriptive, restrictive methods can lead to a lack of innovation and improvements.
· It can be hard to get investment for new ideas because there are no any proven benefits, which is perpetuated by a lack of ability to improve existing patterns.
For all these limitations, it is possible with good organisation practices to be able to work around these requirements. This might be by encouraging minimum viable products (MVPs), allowing colleagues to use new tools in their day to day life, and having governance process that look to solve organisational problems and ongoing reviews of current business processes.
Conclusion
In this blog post, we have given our definition of Patterns, Blueprints, Templates, Standards and Reference Architectures, along with a real-world example and a computing example alongside an exploration of the benefits and limitations of using them.
Have any thoughts? Do you vehemently disagree with our definitions? Have a better computing example? Get in touch to tell us what you think
