One speaks of Vendor lock-in when a company makes itself dependent on a product from an external manufacturer (vendor). In addition to specialist systems(inventory management, claims system, collection and disbursement, etc.), this also frequently occurs with middleware products. An Enterprise Service Bus (ESB), for example, is a very complex product that requires a highly specialized support team. Due to proprietary (i.e., vendor-specific) technology and methods, switching to another product can be extremely difficult and expensive. In many cases, open-source based solutions offer a way out of this trap.
Hub-and-spoke architecture
The integration paradigm of a hub-and-spoke architecture drastically reduces the number of connections between systems or components to that of the systems involved.
Advantages of a hub-and-spoke architecture
A hub-and-spoke architecture consistently implements the integration paradigms - "integration needs a place" and "loose coupling." The so-called bus architectures are also very similar to the hub-and-spoke architecture.
Disadvantages of a hub-and-spoke architecture
The disadvantages of a hub-and-spoke architecture or ESB are the centralized, heavyweight, and proprietary infrastructure. This is accompanied by a corresponding vendor lock-in and an often very high TCO (Total Cost of Ownership). The centralization of technology also massively limits the flexibility of a hub-and-spoke architecture.