Every time you open a website, send an email, join a video call or stream a movie, multiple internet protocols begin working behind the scenes.

These protocols determine how your device finds a server, how data is divided into packets, how those packets travel across different networks and how the information is reconstructed when it reaches its destination.

You rarely see these processes. In most cases, everything happens within milliseconds.

However, without internet protocols, devices would not know how to communicate, websites would not load, emails would not reach their recipients and global networks would not be able to exchange traffic.

This guide explains the most important internet protocols, including:

• TCP/IP
• UDP
• DNS
• DHCP
• HTTP and HTTPS
• FTP, FTPS and SFTP
• SSH
• SMTP
• TLS and SSL
• WebSocket
• QUIC
• BGP

Understanding these protocols can help developers, business owners, system administrators and everyday internet users better understand how modern digital services operate.

What Is an Internet Protocol?

An internet protocol is a defined set of rules that devices follow when communicating across a network.

Computers, servers, routers, smartphones and other connected devices may use different hardware and operating systems. Protocols provide a common communication standard that allows these systems to exchange information reliably.

Different protocols handle different responsibilities.

Some protocols identify where data needs to go. Others ensure that the data arrives correctly, encrypt communications, assign network addresses or determine the route traffic should follow across the internet.

Together, these protocols form the communication framework of the modern internet.

Internet Protocols at a Glance

Protocol	Full Name	Main Purpose
TCP	Transmission Control Protocol	Reliable and ordered data delivery
IP	Internet Protocol	Addressing and routing packets
UDP	User Datagram Protocol	Fast, connectionless data transmission
DNS	Domain Name System	Converts domain names into IP addresses
DHCP	Dynamic Host Configuration Protocol	Automatically assigns network settings
HTTP	Hypertext Transfer Protocol	Transfers website and application data
HTTPS	Hypertext Transfer Protocol Secure	Encrypts HTTP communications
FTP	File Transfer Protocol	Transfers and manages files
SSH	Secure Shell	Provides secure remote server access
SMTP	Simple Mail Transfer Protocol	Sends email between clients and servers
TLS	Transport Layer Security	Encrypts network communication
WebSocket	WebSocket Protocol	Enables persistent, real-time communication
QUIC	Quick UDP Internet Connections	Provides fast and secure transport over UDP
BGP	Border Gateway Protocol	Routes traffic between large networks

1. TCP/IP: The Foundation of the Internet

TCP/IP is not a single protocol. It is a collection of communication protocols that forms the foundation of the internet.

The two central components are:

• TCP, which manages reliable data delivery.
• IP, which manages addressing and routing.

In simple terms, IP determines where the data needs to go, while TCP helps ensure that the data arrives correctly.

How TCP Works

TCP stands for Transmission Control Protocol.

It is a connection-oriented protocol, meaning that two devices establish a connection before transferring application data.

TCP commonly begins with a process known as the three-way handshake.

The TCP Three-Way Handshake

The process consists of three messages:

1. SYN: The client sends a synchronisation request to begin the connection.
2. SYN-ACK: The server acknowledges the request and indicates that it is ready.
3. ACK: The client confirms the server’s response.

Once this handshake is complete, data can begin flowing between the two systems.

TCP breaks the data into smaller units called segments. It assigns sequence numbers to these segments so that they can be tracked and reassembled in the correct order.

If a segment is lost during transmission, TCP can request that it be sent again. It also uses acknowledgements, flow control and congestion-control mechanisms to manage communication.

Because of these features, TCP is commonly used for applications where completeness and accuracy are essential, including:

• Website loading
• File downloads
• Email transmission
• Database connections
• Remote server access

How IP Works

IP stands for Internet Protocol.

It handles the addressing and routing of data across networks. Every device participating in an IP network uses an IP address that helps other systems identify where data should be delivered.

An IP address can be compared to a postal address. It provides destination information, while routers help move packets towards that destination.

There are two widely used versions of IP.

IPv4

IPv4 uses 32-bit addresses.

A typical IPv4 address looks like this:

192.168.1.1

IPv4 provides approximately 4.3 billion possible addresses. Although this initially appeared sufficient, the rapid expansion of internet-connected devices created a global address shortage.

Technologies such as Network Address Translation, or NAT, have helped extend the usable life of IPv4.

IPv6

IPv6 uses 128-bit addresses.

A typical IPv6 address looks like this:

2401:2960::2

IPv6 supports approximately 340 undecillion possible addresses. This dramatically larger address space was designed to support the continued growth of the internet, connected devices, data centres and Internet of Things deployments.

TCP and IP Working Together

When TCP and IP operate together:

• TCP divides data and manages reliable delivery.
• IP addresses and routes the packets.
• Routers forward packets through different networks.
• TCP reassembles the received information in the correct order.

This relationship is why TCP/IP is often described as the backbone of internet communication.

2. UDP: Fast Communication Without a Connection

UDP stands for User Datagram Protocol.

Unlike TCP, UDP is connectionless. It does not establish a formal connection or perform a three-way handshake before transmitting data.

UDP sends packets known as datagrams directly to the destination.

It does not automatically:

• Confirm that packets were delivered
• Retransmit lost packets
• Guarantee packet order
• Prevent duplicate packets
• Establish a persistent connection

This reduced overhead makes UDP fast and lightweight.

Where Is UDP Used?

UDP is commonly used when low latency is more important than perfect delivery.

Typical applications include:

• Online gaming
• Voice-over-IP calls
• Live video streaming
• Video conferencing
• DNS queries
• Real-time broadcasts
• Network monitoring

For example, a missing packet during an online game might cause a brief visual inconsistency. Retransmitting that packet could create a more noticeable delay, making the experience feel less responsive.

Similarly, during a live voice or video call, a small drop in quality may be preferable to freezing the entire conversation while waiting for lost data.

TCP vs UDP

Feature	TCP	UDP
Connection	Connection-oriented	Connectionless
Delivery guarantee	Yes	No
Packet ordering	Yes	No
Retransmission	Yes	No
Overhead	Higher	Lower
Speed	Generally slower	Generally faster
Common uses	Websites, email and file transfers	Gaming, streaming and voice calls

The correct choice depends on the application. TCP prioritises reliability, while UDP prioritises speed and reduced latency.

3. DNS: The Internet’s Naming System

DNS stands for Domain Name System.

It converts human-readable domain names into IP addresses.

People find names such as example.com easier to remember than numerical IP addresses. Computers, however, use IP addresses when locating and connecting to servers.

DNS connects these two systems.

How DNS Resolution Works

When you enter a domain name into a browser, your device first checks whether the address is already stored in a local cache.

If the address is not available, the device sends a query to a DNS resolver. The resolver may be operated by an internet service provider, organisation or public DNS service.

When necessary, the resolver may contact several parts of the DNS hierarchy:

1. Root name servers
2. Top-level domain name servers, such as those responsible for .com or .in
3. Authoritative name servers, which contain the DNS records for the requested domain

The resulting IP address is returned to your device, allowing it to connect to the correct web server.

DNS Caching

DNS responses are stored temporarily in caches.

Caching reduces repeated lookups, improves website-loading speed and decreases the workload placed on DNS infrastructure.

The duration for which a DNS record may remain cached is controlled by its Time to Live, commonly called TTL.

Common DNS Record Types

A Record

Maps a domain or hostname to an IPv4 address.

AAAA Record

Maps a domain or hostname to an IPv6 address.

CNAME Record

Creates an alias that points one hostname to another hostname.

MX Record

Identifies the mail servers responsible for receiving email for a domain.

TXT Record

Stores text-based information and is frequently used for domain verification and email-security policies.

NS Record

Identifies the authoritative name servers for a domain.

DNS Security

Traditional DNS queries are generally not encrypted. Depending on the network configuration, they may be visible to network operators or vulnerable to manipulation.

Encrypted DNS technologies include:

• DNS over HTTPS, or DoH
• DNS over TLS, or DoT

DNSSEC serves a different purpose. It helps verify the authenticity of DNS responses and protects against certain forms of DNS manipulation, but it does not encrypt the query itself.

4. DHCP: Automatic Network Configuration

DHCP stands for Dynamic Host Configuration Protocol.

It automatically provides devices with the network configuration they need when they connect to a local network.

Without DHCP, users or administrators would need to manually configure details such as:

• IP address
• Subnet mask
• Default gateway
• DNS server
• Lease duration

At home, the Wi-Fi router normally functions as the DHCP server. In larger offices, schools and data centres, dedicated DHCP systems may manage hundreds or thousands of devices.

The DHCP DORA Process

The standard DHCP allocation process is commonly remembered as DORA:

Discover

The device broadcasts a DHCP Discover message to locate an available DHCP server.

Offer

A DHCP server responds with an available IP address and configuration information.

Request

The device requests the offered address.

Acknowledge

The server confirms the lease and provides the final network settings.

This process usually completes automatically within seconds.

DHCP Lease Time

A DHCP-assigned IP address is normally provided for a limited period known as a lease.

The device can attempt to renew the lease before it expires. Leasing allows the network to reuse addresses after devices disconnect and prevents unnecessary address exhaustion.

DHCP also helps reduce IP-address conflicts by keeping track of the addresses allocated to connected devices.

5. HTTP and HTTPS: How Websites Communicate

HTTP stands for Hypertext Transfer Protocol.

It is an application-layer protocol used to transfer information between web clients and servers.

When you open a website, your browser sends an HTTP request. The server processes that request and returns an HTTP response containing content or instructions.

That response may include:

• HTML
• CSS
• JavaScript
• Images
• Videos
• Fonts
• API data

HTTP follows a request-and-response model. The client requests a resource, and the server returns a response.

Why Basic HTTP Is Not Secure

Traditional HTTP does not encrypt the transmitted information.

Anyone capable of intercepting the connection may potentially view or modify unencrypted traffic. This makes plain HTTP unsuitable for passwords, payment information, private messages and other sensitive data.

How HTTPS Protects Data

HTTPS stands for Hypertext Transfer Protocol Secure.

HTTPS uses TLS to encrypt communication between the client and server.

It provides three important protections:

Encryption

The transmitted data is converted into a form that unauthorised parties cannot easily read.

Authentication

A digital certificate helps verify that the client is communicating with the intended website or service.

Integrity

TLS helps detect whether the data has been modified during transmission.

The padlock displayed by modern browsers indicates that the browser has established an encrypted HTTPS connection. It does not, by itself, guarantee that the website or business is trustworthy.

Today, HTTPS should be considered essential for every production website, not only ecommerce and banking platforms.

6. FTP, FTPS and SFTP: Transferring Files

FTP stands for File Transfer Protocol.

It is one of the oldest protocols used for transferring and managing files across a network.

FTP allows authorised users to:

• Upload files
• Download files
• Rename files
• Delete files
• Create directories
• Browse remote server storage

FTP uses a client-server model and commonly operates with separate control and data connections.

The control connection handles commands and authentication, while the data connection transfers directory listings and files.

Active and Passive FTP

FTP can operate in active or passive mode.

In active mode, the server creates the data connection back to the client. This can cause difficulties when the client is behind a firewall or NAT system.

In passive mode, the client initiates both connections. Passive FTP is therefore more common in modern network environments.

The Security Problem With FTP

Standard FTP does not encrypt usernames, passwords or file contents.

For secure file transfers, organisations generally use FTPS or SFTP.

FTPS

FTPS is FTP secured using TLS encryption.

SFTP

SFTP stands for SSH File Transfer Protocol.

Despite the similar name, SFTP is not simply FTP with security added. It is a separate file-transfer protocol that operates through SSH.

For most server-management environments, SFTP is preferred because it provides encrypted authentication and file transmission through a single secure connection.

7. SSH: Secure Remote Server Access

SSH stands for Secure Shell.

It provides encrypted remote access to computers and servers over a network.

System administrators, developers, DevOps engineers and hosting providers use SSH to manage infrastructure without requiring physical access to the machine.

SSH can be used to:

• Log in to a remote server
• Execute commands
• Manage services
• Edit configuration files
• Install software
• Transfer files
• Forward ports
• Create secure tunnels

SSH Authentication

Users can authenticate through passwords or cryptographic key pairs.

An SSH key pair contains:

• A private key stored securely on the user’s device
• A public key installed on the remote server

The private key should never be shared. When correctly configured, key-based authentication is generally more resistant to password guessing and credential theft.

Additional protections may include:

• Disabling direct root login
• Restricting access by IP address
• Using multi-factor authentication
• Limiting failed login attempts
• Regularly reviewing authorised keys
• Keeping the SSH server updated

8. SMTP: Sending Email Across the Internet

SMTP stands for Simple Mail Transfer Protocol.

It is used to send email from clients to mail servers and to transfer messages between mail servers.

When you send an email, SMTP helps move the message from your email application to the sending mail server and then towards the recipient’s mail system.

SMTP handles sending, but it is not normally responsible for synchronising and reading received messages.

Other protocols are used for that purpose.

IMAP

Internet Message Access Protocol synchronises email while keeping messages stored on the mail server.

POP3

Post Office Protocol version 3 traditionally downloads messages from a mail server to a device.

SMTP Security

The original SMTP design did not include modern encryption and authentication protections.

Today, email services may use:

• STARTTLS to upgrade an existing connection to an encrypted TLS connection
• Implicit TLS, sometimes informally called SMTPS
• SMTP authentication for authorised message submission
• SPF, DKIM and DMARC to reduce spoofing and improve domain-level email authentication

SMTP also provides delivery-status information. When a message cannot be delivered, the sending system may receive a bounce message explaining the reason.

9. TLS and SSL: Protecting Data in Transit

TLS stands for Transport Layer Security.

It protects data travelling between applications, browsers, APIs, email systems and servers.

TLS replaced SSL, or Secure Sockets Layer.

SSL is now obsolete because its versions contain known security weaknesses. However, the term “SSL certificate” is still commonly used when people are actually referring to certificates used with TLS.

What TLS Provides

TLS delivers three core security properties:

• Encryption: Prevents intercepted data from being easily read.
• Authentication: Helps confirm the identity of the server.
• Integrity: Helps ensure that transmitted data has not been altered.

TLS is used in technologies including:

• HTTPS
• Secure email transmission
• FTPS
• API communication
• Database encryption
• Secure application connections

TLS 1.3 reduces unnecessary handshake steps, removes several older cryptographic options and improves both connection speed and security compared with previous versions.

10. WebSocket: Real-Time, Two-Way Communication

Traditional HTTP communication usually follows a request-and-response pattern.

A client sends a request, the server returns a response and the interaction ends unless another request is made.

WebSocket provides a persistent, bidirectional communication channel between a client and server.

Once established, both sides can send data without creating a new HTTP request for every update.

Where WebSocket Is Used

WebSocket is useful for applications that require continuous or near-instant updates, including:

• Live customer-support chat
• Multiplayer games
• Trading dashboards
• Collaborative documents
• Real-time notifications
• Monitoring systems
• Live sports updates

A WebSocket connection normally begins as an HTTP request and then upgrades to the WebSocket protocol.

Secure WebSocket connections use wss://, which protects the connection using TLS. It serves a role similar to HTTPS for standard web traffic.

11. QUIC: Faster and More Resilient Web Transport

QUIC was initially developed by Google and later standardised for wider internet use.

It operates over UDP while implementing important features commonly associated with TCP and TLS, including:

• Reliable delivery
• Congestion control
• Stream management
• Encryption
• Connection establishment

QUIC is the transport protocol used by HTTP/3.

Why QUIC Can Improve Performance

Traditional HTTPS connections using TCP may require a TCP handshake followed by a TLS handshake.

QUIC integrates security into the transport protocol and can reduce the number of round trips needed to establish a secure connection.

It also supports multiple independent streams within one connection.

With HTTP/2 over TCP, packet loss can temporarily delay multiple streams sharing the same TCP connection. QUIC reduces this problem because the loss of data in one stream does not necessarily block unrelated streams.

This can improve performance on:

• Mobile connections
• High-latency networks
• Unstable Wi-Fi
• International connections
• Video-streaming platforms
• Content-heavy websites

QUIC should not be described simply as “HTTP over UDP.” It is a complete transport protocol, while HTTP/3 is the HTTP version that operates over QUIC.

12. BGP: How Traffic Moves Between Global Networks

BGP stands for Border Gateway Protocol.

It is the routing protocol used to exchange reachability information between autonomous systems.

An autonomous system is a large network or group of networks operated under a common routing policy. Internet service providers, cloud companies, telecommunications providers, universities and data-centre operators may each operate an autonomous system.

BGP allows these networks to announce which IP address ranges they can reach.

Other networks evaluate these announcements and select routes based on factors such as:

• AS path
• Local preference
• Routing policies
• Network relationships
• Route availability
• BGP attributes

BGP does not simply choose the geographically shortest or lowest-latency route. Routing decisions are heavily influenced by technical and commercial policies.

BGP Security Risks

Traditional BGP was built around trust between network operators.

An accidental configuration error or malicious route announcement can cause traffic to be redirected, dropped or sent through an unintended network.

These events may result in:

• Website outages
• Service unavailability
• Traffic interception risks
• Regional connectivity problems
• Route leaks
• BGP hijacks

RPKI, or Resource Public Key Infrastructure, helps network operators verify whether an autonomous system is authorised to announce a particular IP prefix.

Route Origin Validation can then be used to accept, reject or deprioritise invalid route announcements according to the operator’s routing policy.

How These Internet Protocols Work Together

Loading a secure website may involve several protocols operating in sequence.

For example:

1. DHCP provides your device with an IP address, gateway and DNS settings.
2. DNS finds the IP address associated with the website’s domain.
3. IP addresses and routes packets towards the destination server.
4. TCP or QUIC establishes and manages transport between the two systems.
5. TLS encrypts the communication and authenticates the server.
6. HTTP or HTTP/3 transfers the website content.
7. BGP helps networks determine how traffic should travel across the wider internet.
8. WebSocket may create a persistent connection when the website includes live chat or real-time features.

No single protocol powers the entire experience. The internet functions because multiple specialised protocols work together in layers.

Why Internet Protocols Matter for Website and Hosting Performance

Internet protocols directly influence website speed, reliability, security and accessibility.

A hosting provider’s infrastructure affects how efficiently these protocols operate.

Important factors include:

Network Latency

The physical and network distance between users and the server affects how long DNS lookups, TCP handshakes, TLS negotiation and data transfers take.

Hosting closer to the intended audience can reduce round-trip time and improve application responsiveness.

Routing Quality

Strong BGP connectivity and reliable upstream network providers help traffic reach the server through stable and efficient routes.

Poor routing can create unnecessary delays even when the server itself is powerful.

DNS Performance

Fast and correctly configured DNS infrastructure helps users locate websites more quickly.

DNS redundancy also reduces the risk of a single DNS failure making a website unreachable.

TLS Configuration

Modern TLS versions, properly configured certificates and secure cipher settings protect user data without creating unnecessary connection overhead.

Protocol Support

Modern web servers can support technologies such as HTTP/2, HTTP/3, IPv6 and WebSocket to improve performance and compatibility.

Infrastructure Reliability

Protocols cannot compensate for unstable electricity, unreliable cooling, overloaded servers or weak network connectivity.

Reliable hosting requires both correctly configured software and dependable physical infrastructure.

Internet Protocols and NCXHost Infrastructure

NCXHost operates data-centre and server infrastructure designed for businesses, developers and organisations that require reliable connectivity, secure server access and low-latency hosting.

Our infrastructure supports services such as:

• Dedicated servers
• Virtual private servers
• GPU servers
• Windows virtual machines
• Colocation
• Custom server deployments
• Secure remote management
• IPv4 and IPv6 connectivity

Choosing the right server location and network infrastructure can improve how efficiently protocols such as TCP, QUIC, DNS, TLS and BGP serve your users.

For organisations serving customers in Assam and Northeast India, locally hosted infrastructure can significantly reduce network distance compared with servers hosted thousands of kilometres away.

Frequently Asked Questions

Conclusion

The internet is not powered by one single technology.

It relies on a layered collection of protocols that address different communication requirements.

TCP manages reliable delivery. IP provides addressing and routing. UDP supports low-latency transmission. DNS translates names into addresses. DHCP configures devices. HTTP transfers web content. TLS protects communication. SSH enables secure server administration. QUIC improves modern web transport, while BGP connects networks across the world.

These protocols remain mostly invisible to users, but they affect nearly every digital interaction.

Understanding how they work provides a clearer picture of why websites load quickly or slowly, why secure connections matter, how servers communicate and how data successfully travels across the global internet.