Architetture IT per il Retail ai tempi del Cloud.

Introduction

Even today, IT for Retail is struggling inside the dilemma between Centralized architectures, with a single database (db) to which all stores access in real time, and Departmental architectures, with a db in every store replicated periodically to the center. The Centralized architecture strengths are the general availability of current data and technical simplicity, while the defects are vulnerability to failures in central system or in communication lines and limited scalability. The Departmental architecture offers specular advantages and disadvantages: good resilience but increased management complexity and lack of a “single truth”. To decrease the Centralized architectures shortcomings, each workstation may be coupled with a local Back-up system, but with a complexity and cost increase. In the case of Departmental solutions, replications frequency can be increased, but reducing efficiency and without reaching a constantly updated view of the entire chain. For these reasons, we are witnessing the transition from a traditional architecture to another. After experiencing the limitations of one, it is changed but soon new restrictions are discovered.

The importance of architecture

The architecture, whether applied to IT or buildings, is the meeting point between aspirations and technology, both in constant evolution. The passage from first to second industrial revolution has been also a shift from vertical to horizontal factories triggered by the change from steam/hydraulic power to electric motors embedded in each machine. Internet and cloud computing have triggered the third industrial revolution, so it’s inevitable moving to new IT architectures. The traditional ones are focused inside of the company and for this reason can be defined “introverted”, while in the new millennium requires “extroverted” architectures in order to facilitate cooperation with product/service suppliers and especially with customers, massively on the Cloud with their Tablets and SmartPhones.

The Distributed and Services Oriented Architecture

The Distributed architecture in the Cloud age is based on services running both inside the Cloud and in peripheral devices (PC, Tablet, SmartPhone), cooperating together in order to achieve performance and efficiency otherwise impossible with traditional architectures.

With “distributed” we mean something different from Parallel Computing as the Map-Reduce in Big Data or Load Balancing in Web sites, where the central service is only meant to distribute the tasks to the subsystems working in parallel and, finally, to consolidate the results. It is not even meant to indicate the absence of any central system as for the Internet, designed with no “single point failure” to be invulnerable. Rather we mean “cooperation” where every system performs the most appropriate tasks for its context and exchanges messages according to a predefined orchestration. The Apps popularized by SmartPhones are a perfect example of this new distributed intelligence that fully exploits both local and Cloud processing capabilities. According to this architecture, the POS (Point od Sale) manage locally price look-up, promotions and customers data in order to issue sales documents at full speed and without depending on external faults, while Cloud services manage, among others, Stock, Coupons and Gift Cards balance.

The word “service” in the previous definition indicates a software component specialized in a specific functionality, with its own processing and data management capability, cooperating with other services by means of high-level and business-oriented standard messages. XML or JSON data formats and REST or SOAP protocols are independent from any particular SW technology or language in order to facilitate reuse and integration. These messages are asynchronous (like eMail) in order to improve scalability, being queued at peak times and immediately processed during the valleys. This is why the SOA (Service Oriented Architecture) and Cloud Computing makes true the dream of IT systems tailored to each company need, built by putting together standard services through APIs (Application Programming Interfaces), as if they were Lego blocks.