Enterprise service buses (ESBs) continue to be the backbone of integration infrastructure of many large enterprises. The upcoming Ovum report, 2017 Trends to Watch: API-led and Cloud-based Integration, elaborates on the gradual demise of service-oriented architecture (SOA) as a heavyweight “big bang” solution architectural approach and examines why ESBs continue to enjoy a successful independent existence as a robust piece of middleware.
ESBs are good for heavy lifting
ESBs, which are usually thought of as a key component of an SOA, also have an independent existence. As a robust piece of middleware enabling service integration, ESBs cater for those complex integration and messaging requirements that an iPaaS solution will struggle to meet. Low-latency messaging, data-intensive integration processes, and real-time mediation of varied messaging standards/protocols are use cases where enterprises definitely need an ESB. While these core IT-centric integration capabilities are not marketed as much as those aimed at meeting digital business needs, it is difficult to think of any comprehensive middleware stack without an ESB as its backbone. ESBs will continue to play a key role in all large enterprises as they focus on meeting emerging digital business integration challenges. While this sub-segment of the middleware market will probably never achieve double-digit growth, large enterprises will continue to invest in upgrades of their existing ESBs.
The state of SOA adoption has been a highly debated topic, and these discussions have thrown up apparently contradictory viewpoints. The traditional view of SOA suggests that enterprises have invested a lot of time and money to sort out means to an end, and still failed to realize any significant business value. SOA, in its heyday, promised much more than service integration, but in most of the successful implementations, that is all enterprises could achieve after several years of heavy lifting. If implemented as a “big bang” solution architecture, SOA is overkill in the light of persistent time and IT budget constraints, and the need for agile integration to cater for digital business needs.
Microservices and API-led architectural approaches follow some of the core SOA principles, although with a specific focus on getting things done. Lightweight SOA, with an ESB at its core and web services linked to specific functions, is a “good enough” proposition for meeting relatively complex hybrid integration requirements. Ovum ICT Enterprise Insights survey results show that a fifth of respondent large enterprises have strategic investment planned for ESBs. This is not surprising because enterprises need to upgrade existing versions of ESBs to access new features and capabilities, including better federation with cloud-based integration platforms.
Enterprise and solution architects often face a dilemma when it comes to a choice between "good enough" architecture and a robust architectural approach that meets long-term business needs but calls for significant changes and investments. In the context of SOA, the implementation of an ESB, with all relevant underlying services and APIs, corresponds to a "good enough" architecture that espouses the use of a standards-based flexible infrastructure layer (middleware) for service integration.
Saurabh Sharma, Senior Analyst, Infrastructure Solutions