Lemonjar mTier Implementation


Lemonjar mTier is a multi tier architecture to implement Koha ILS. It is a multi-tier application architecture, a modular client-server architecture that consists of a web service tier, an application tier and a data tier, or also known as Web – Application – Database.
The data tier stores information, the application tier handles logic and the web service tier is handling the load balancing and web service that communicates with the other two tiers.

The three tiers are logical, not physical, and may or may not run on the same physical server. It can be running in 3 separated servers/ virtual servers.

Web Service Tier

web server which can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache for Koha ILS. The Web Service Tier is a high-performance HTTP server and reverse proxy, as well as an IMAP/POP3 proxy server. The Web Service Tier is known for its high performance, stability, rich feature set, simple configuration, and low resource consumption.

Application Tier

The application tier, which may also be referred to as the logic tier, the Koha ILS engines the application’s core functions. This application tier can either be hosted on distributed servers in the cloud or on a dedicated in-house server, depending on the requirement of the library, such as how many concurrent users and what is the response time, to identify the processing power for the application.

Data Tier

The data tier consists the Koha ILS database. This tier may also be referred to as the storage tier and can be hosted on-premises or in the cloud. Koha ILS is adopting MySQL or MariaDB. Please refer also Lemonjar DB Policy for storing/async/sync the data from the main database to another backup server to achieve 0 data loss.