ITPEC FE Morning October 2020 Question 14

Light static requests stay on the web server and heavy dynamic ones go to the AP server — separating the two tiers distributes the load by kind of request.

In a three-tier web system the web server returns static content (HTML files, images, style sheets) and forwards requests that need processing to the application server, which runs the business logic and talks to the database. On separate machines each tier can be sized and scaled for its own load, and cheap static requests never wait behind heavy ones.

Answer (d)

Why not others:

• •(a) — business logic belongs on the AP server, not the web server; placing it there is not what the separation brings
• •(b) — character encoding is settled by the charset declared between browser and server; moving the servers apart does nothing about garbled text
• •(c) — the client's execution environment is the browser, and screens still travel to it for each request; separating the servers does not reduce that traffic

Key rule: Splitting tiers onto separate servers is about distributing load and scaling each tier independently: presentation and static files on the web server, business logic on the AP server, data on the DB server.

System Component · AI-written, may contain errors