This document discusses different integration architectures: point-to-point, hub-and-spoke, distributed, and service-oriented. It notes the advantages and disadvantages of each. Hub-and-spoke was an early formal integration technology but does not scale well. Distributed integration addresses scalability by distributing work across multiple agents. Service-oriented architecture uses loosely coupled web services. The document discusses how enterprise service buses have become the standard for creating service-oriented architectures, noting their core features and benefits like scalability, ease of expansion, and support for incremental adoption.