Continuing from the previous post which dealt with the core concepts around performing authentication and authorisation in a distributed environment, this post expands upon those concepts, looking at additional factors for authorisation decisions, including supplementary information, authentication challenges and risk assessment. While basic authentication and authorisation requirements can be met through the use of JWTs and OAuth, this post shifts to tackling bespoke requirements, outlining potential services which could provide capabilities above and beyond what is captured in those standards.
In the previous post in this series we examined at a high-level how responsibilities for authentication and authorisation are distributed in a micro-services architecture. In this post, the strategies and technologies that underpin the implementation of authentication and authorisation will be explored further, with the core access management services providing authentication services, which support individual services performing authorisation. This discussion is actually split across two posts, as authentication and authorisation are core parts of the access management services, and require extensive discussion, with this post focusing upon the core capabilities, and the following post focussing upon more advanced authentication and authorisation requirements.
An ongoing trend, as organisations increasingly adopt cloud-native development approaches, is from centralised services, to widely distributed services. This shift requires a rethink about how access management is delivered, in terms of aligning with this model in development practice, as well as accommodating the radical effect that this has on deployment architecture. I have previously alluded to this shift as being from ‘perimeter-based access management’ to ‘centralised access management’, and how this is able to accommodate the increasing adoption of distributed infrastructure and services.
I initially began writing a post which would explore this concept in more detail, though it quickly grew beyond what could be easily captured within a single post. As a result, in order to give the topic justice, I will break this into a number of posts, beginning, in this post, by exploring what Access Management even looks like in this sort of architecture, then going into more detail about strategies for implementing a micro-services approach to access management.
There are no shortage of acronyms in the security space, and shifting towards centralised-security, rather than perimeter-based-security, has added even more. As I have been playing with solutions around centralised identity services, such as Oracle’s Identity Cloud Service, I have found myself spending more and more time in IETF RFCs in order to understand these concepts. While there is a lot of value in the standards documents, they assume a lot of knowledge and I often found myself wishing for a slightly more approachable, high level description of the elements I was dealing with. While there is something tempting about being part of the secret ‘We read the security RFCs’ club, I resisted this, and took it upon myself to provide this higher level overview of these important concepts.