Session 1: 21st July 2022

Deatiled topics and the corresponding reference links

Connect to GITHUB and create a Repository

• Set up GITHUB account through authorization along with Password protection / Repositories for practice
• Create README.md file for reference purpose and index html for the initial sync
• Create the Repository for 'Private' usage and choose all the default settings

Overview of Vercel & Set up Vercel Account

1. Vercel enables developers to host websites and web services that deploy instantly, scale automatically, and require no supervision.
2. Deploying website in Vercel through GitHub is super easy and it takes care of the below features:

• Deploying the site to a global CDN
• Ensuring your site is always online by intelligently monitoring and automatically scaling frontend capacity
• Taking care of SSL certificates (Secure Sockets Layer) or HTTPS on your behalf

a. SSL certificates make SSL/TLS encryption possible for the websites to make them more secured, and they contain the website's public key and the website's identity, along with related information.
b. SSL certificate is required to maintain Encryption, Authentication & Https features


• Types of SSL Certificates:
  I. Single Domain : applies to only one domain
  II.Wildcard : applies to one domain and it's corresponding sub-domains
  III.Multi Domain : applies to multiple unrelated domains including Domain-Validation, Organization - Validation & Extended - Validation

Overview of CDN

Content Delivery Network (CDN) is a system of distributed servers that accelerates internet content delivery and helps to reduce latency while accessing websites.
CDN’s job is to virtually shorten the distance between the server and the user by caching the static contents (images, videos, CSS, JavaScript files) based on the geographic location.

To minimise the distance between the origin server and the user making a request, CDNs store cached content in various areas or points of presence (PoPs).
Each PoP is equipped with several caching servers for content delivery.

• Push CDN
• Pull CDN

CDN & it's benefits

Overview of DNS

CDN basically archives through DNS- Domain Name System which translates domain names to IP addresses so browsers can load Internet resources.
4 DNS servers involved in loading a webpage

• DNS Recursor
• Root Nameserver
• TLD Nameserver
• Authoritative Nameserver

Recursive DNS Resolver : The recursive resolver is the computer that responds to a recursive request from a client and takes the time to track down the DNS record.
Authoritative DNS Server: Holds actual DNS resource records
an additional nameserver will be added to the sequence after the authoritative nameserver, which is responsible for storing the subdomain’s CNAME Records.

DNS look up contains several steps. DNS Steps
There are three types of DNS Queries:

• Recursive Query
• Iterative Query
• Non-Recursive Query