Functional:

• User should be able to enter a link and receive and shortened one
• Link should persist
• No two links should share the same

Non-Functional:

• Scalable system
• fault tolerant for link redirection

Capacity estimation

• Say we have 1 billion links stored, if 10% of them are used a day that's 70,000 redirects a minute.

API design

• Some sort of REST API where we can retrieve the links from our database, perhaps a request system where we pass a link and are returned

Database design

Fragmented data base with horizontal expansion using keys to sort data into sharded servers.

High-level design

see chart

Request flows

Two scenarios. Client creating a link and client referencing one. In each path we move through a load balancer then depending on if we're creating or generating, we pass through a generator/decoder. We then store our link in the key store and then port forward if we're clicking on the link.

Detailed component design

see chart

Trade offs/Tech choices

ignore

Failure scenarios/bottlenecks

key store speed could be an issue - caches could be a solution to this

Future improvements

Ignore