Different Types of Servers

In the realm of eCommerce architecture, the deployment and management of various types of servers are fundamental to ensuring the robustness, scalability, and security of online retail platforms. These servers, each with its distinct function, work in concert to deliver a seamless shopping experience. Here, we delineate the primary categories of servers utilized within an eCommerce framework and elucidate their respective roles:

1. Web Servers:
   • Function: Web servers are pivotal in handling incoming HTTP requests from clients, such as web browsers, and serving them with the requested web pages or resources. They act as the gateway through which end-users interact with an eCommerce website.
   • Examples: Apache HTTP Server, Nginx, Microsoft Internet Information Services (IIS).
2. Application Servers:
   • Function: Application servers provide a runtime environment for eCommerce applications to execute. They manage the business logic and facilitate the interaction between the user interface on the front end and the database on the back end. This includes processing product searches, transactions, and user authentication.
   • Examples: Apache Tomcat, Microsoft ASP.NET, Red Hat JBoss.
3. Database Servers:
   • Function: Database servers are the backbone of any eCommerce platform, responsible for storing and managing critical data such as product catalogs, customer information, and transaction records. They ensure data integrity, security, and fast retrieval of information.
   • Examples: MySQL, Microsoft SQL Server, Oracle Database.
4. File Servers:
   • Function: File servers store and manage the static content of an eCommerce site, such as product images, videos, and documents. They enable efficient management and delivery of these resources to the web and application servers.
   • Examples: Network Attached Storage (NAS) devices, Microsoft Windows Server with file services.
5. Mail Servers:
   • Function: Mail servers are essential for handling the email communications of an eCommerce operation. This includes sending transactional emails, marketing newsletters, and customer service correspondences.
   • Examples: Postfix, Microsoft Exchange Server, Exim.
6. Cache Servers:
   • Function: Cache servers are employed to speed up the delivery of frequently accessed information by temporarily storing copies of files and data. This reduces the load on application and database servers and improves site performance.
   • Examples: Memcached, Redis, Varnish.
7. Search Servers:
   • Function: Search servers enhance the search functionality of an eCommerce site by indexing the site content and providing fast, relevant search results to user queries. They are optimized for handling complex search operations across vast product catalogs.
   • Examples: Elasticsearch, Apache Solr, Sphinx.
8. Security Servers:
   • Function: Security servers protect the eCommerce ecosystem from various cyber threats. They manage firewalls, SSL certificates for secure transactions, and perform intrusion detection and prevention.
   • Examples: Hardware-based firewall appliances, Unified Threat Management (UTM) systems, SSL certificate managers.
9. Content Delivery Network (CDN) Servers:
   • Function: Although not servers in the traditional sense, CDNs comprise a network of servers distributed globally to deliver content to users from the nearest geographical location. They are crucial for enhancing the speed and reliability of content delivery on a global scale.
   • Examples: Akamai, Cloudflare, Amazon CloudFront.

Each type of server plays a critical role in the architecture of an eCommerce system, ensuring efficient operations, enhanced performance, and a secure environment for both the business and its customers. Integrating and optimizing these servers in alignment with the specific needs of an eCommerce platform is fundamental to its success.

A server is a computer that stores content and then delivers that content when it's requested by a client. The term "server" can refer both to a program that performs these operations and to the machine that runs server programs.
The primary function of the server is to coordinate the exchange of data between the users (called nodes) or other networks. Because all data must pass through the server, the more data that is passed, the slower the server becomes. To off-load some of the more demanding tasks, general purpose servers pass these tasks to specialized servers for processing. These 'specialized' servers are optimized to perform one particular task, thereby improving the throughput of the general server.
As an example, when calling for information through your local telephone, you dial 411 for local information, or (Area Code) 555-1212 for information outside your area. This system is more efficient than requiring the local operator to handle all information calls. The same is true for servers. Whenever the general purpose server receives a special request, it routes that request to a specialized server to handle. Let's see what some of these special servers do.

A directory server is similar to a DNS server, but instead of translating Internet domain names to a number, it is used to translate user names to a LAN address. The protocal used is LDAP (Lightweight Directory Access Protocol).
An LDAP is essentially a two-column list:

1. user names on one side and
2. network card addresses for each PC on the LAN, on the other.

Like DNS, a directory server permits users to send files to a LAN destination by name, rather than using numbers.

A file server simply stores thousands of files and is especially designed to locate and transmit those files as rapidly as possible.

Like a file server, an FTP server is dedicated to transferring files also, but to transfer those files via the Internet. The primary difference between these servers is that special security and transport capabilities are required on the FTP server.
In the next lesson, the additional types of servers and their features and functions will be discussed.