The Domain Name System (DNS) is the phonebook of the internet — it translates human-readable domain names like kaptaindevops.com into IP addresses that computers use to communicate, such as 13.248.155.104.
Without DNS, we’d have to remember long numeric addresses instead of easy-to-read names.
DNS is one of the core foundations of how the internet operates — and AWS’s Route 53 service brings DNS management into the cloud era.
DNS is a distributed, hierarchical naming system that helps locate computers and services on the internet or private networks.
When you type a URL in your browser:
This all happens in milliseconds.
| Component | Description |
|---|---|
| DNS Resolver | The server (often from your ISP or cloud) that starts the DNS lookup process. |
| Root Server | Top of the DNS hierarchy. Directs queries to TLD servers. |
| TLD (Top-Level Domain) Server | Stores info for domain suffixes like .com, .org, .in, etc. |
| Authoritative Name Server | Holds the actual DNS records for a domain (managed by Route 53 or other providers). |
| DNS Cache | Temporary local storage to reduce repeated lookups and speed up resolution. |
Each domain has DNS records, which define how traffic should be routed.
| Record Type | Description | Example |
|---|---|---|
| A | Maps a domain to an IPv4 address | api.kaptaindevops.com → 192.0.2.44 |
| AAAA | Maps a domain to an IPv6 address | api.kaptaindevops.com → 2001:db8::1 |
| CNAME | Alias to another domain name | www.kaptaindevops.com → kaptaindevops.com |
| MX | Mail exchanger for email routing | kaptaindevops.com → mail.protection.outlook.com |
| TXT | Stores text info (e.g., SPF, DKIM, domain verification) | "v=spf1 include:_spf.google.com ~all" |
| NS | Lists authoritative name servers | ns-110.awsdns-10.com |
| PTR | Reverse DNS (IP → Domain) | 13.248.155.104 → kaptaindevops.com |
| SRV | Defines service and port for specific protocols | _sip._tcp.example.com → sipserver.com:5060 |
| SOA | Start of Authority — contains zone metadata | Serial, refresh rate, TTL values |