What is difference architectural design vs high-level design

Question

Can some one explain me what is the difference between architectural design vs high-level design.

It will be helpful to me if you explain by example: Lets say I want to build simple android online shopping application, in that case what should I put in my architectural design and high-level design?

I have the following high-level requirements:

Login
Settings
Search
Cart
Billing

Answer 1

Seems you are asking 2 questions:-

1. Difference between the terms architectural design & high-level design
2. What would my android shopping application design look like

I will answer the first but you are unlikely to get someone to give you the second one. Best to google for ideas.

Architectural design

You need to get a basic understanding of these different types of architecture and then you will realise why this question is way too generic

• Enterprise Architecture
• Solution Architecture
• Application Architecture
• Network Architecture
• Security Architecture
• ... there are more...

High-level design

This is a very broad term which you might get an infinite number of definitions for but a common one would be a design which just shows the components in a system (the system could be very large or very small). Since it seems you are asking about Application Architecture with your shopping cart app, this would mean you might have a diagram which shows things like the following but not the details of how each one is implemented:-

• Main classes/interfaces in the code
• Some sort of persistence store
• Cache
• Remote systems your app interracts with

Answer 2

High Level Design (HLD) is more specific than architecture.

Architecture is about considering various constraints and making informed decisions, such as:

• Which technology to use.
• System quality attributes (e.g. performance, availability, security, usability, and so on), and what the relative priority of these is (ties into the non-functional requirements).
• Ensuring the solution can be well supported once it's in operation.
• Aligning the solution with the organizations technology strategy or enterprise architecture, etc.

High Level Design is about starting to make the architecture real:

• Logically defining components of the system, and what their roles are, and how they inter-relate.
• Referring to named technology, e.g. calling out specific parts of your chosen technology stack that need to be used, which specific frameworks or 3rd party libraries you will use.
• Calling out which specific Line of Business systems and their specific APIs that you need to integrate with.

So to take your example, the architecture might define:

• That you're building an android app to do shopping.
• That the data it will surface will come from some online services.
• What data is stored on the device, if any - e.g. user preferences.
• That users can authenticate using social media, e.g. Google.

...therefore the HLD should define:

• The specific android version your will target / support, specific dependencies etc.
• Exactly where the data services are located, exactly which ones, what data objects & values they will be providing.
• The logical data design (probably field level) for any data you need to store on the device.
• Specifics regarding how you will perform the authentication with social media providers, the code libraries to be used, etc.