DNS over HTTPS (DoH) Explained

Direct Answer

DNS over HTTPS (DoH) is a security protocol that encrypts your DNS queries by sending them over a standard HTTPS connection. This prevents third parties, including your Internet Service Provider (ISP), from seeing, tracking, or altering the websites you attempt to visit.

Overview

Traditional DNS queries are sent in “plain text” over port 53. This means anyone sitting between your computer and the DNS server—such as your ISP or a hacker on a public Wi-Fi—can see every domain you look up. DoH solves this by wrapping the DNS request inside an encrypted HTTPS packet. By using port 443 (the standard port for secure web traffic), DoH traffic is indistinguishable from regular web browsing, making it extremely difficult to block or hijack.

DNS over TLS (DoT) Explained

Direct Answer

DNS over TLS (DoT) is a protocol used to encrypt DNS queries to ensure they remain private and secure from interception. Unlike DoH, which hides DNS traffic inside web traffic, DoT uses a dedicated port (853) and is primarily used for system-wide or router-level encryption.

Overview

The primary goal of DoT is to provide a “clean” encryption layer for DNS. By using the Transport Layer Security (TLS) protocol, it creates a secure tunnel between your device and the DNS resolver. Because it operates on its own port, it is easier for network administrators to monitor and manage, but it is also easier for ISPs to block if they choose to do so.

DNS Propagation: Why Site Updates Take 24-48 Hours

Summary

DNS Propagation is the period of time it takes for changes to DNS records (like switching your website to a new host) to be updated across every DNS server in the world. During this time, some users might see the new site, while others still see the old one.

Overview

When you update a DNS record, the change happens instantly on your domain registrar’s server. However, there are millions of recursive DNS servers globally (owned by ISPs, Google, etc.). These servers do not check for updates every second; they wait for the “cache timer” (TTL) of the old record to expire before asking for the new one.

Direct Answer

To identify whether an internet problem lies with your router, your ISP, or an international cable, you need specialized tools. WinMTR and MTR are the industry standards for analyzing hop-by-hop latency, while WiFi Analyzer helps resolve local wireless interference.

Overview

Standard speed tests (like Speedtest.net) only show your maximum bandwidth. They rarely reveal why your connection “drops” or why gaming is laggy. Diagnostic tools allow you to “see” the path your data takes and identify the exact point of failure.

Home Network Security Guide

Direct Answer

Securing your home network is the first line of defense against cyber threats. This guide provides a checklist for hardening your router, protecting your connected devices, and preventing common attacks used in the local environment.

Overview

Most home networks in Bangladesh are vulnerable due to default configurations provided by ISPs and a lack of awareness about basic security features. By following a few simple steps, you can significantly reduce the risk of unauthorized access to your data.

HTTPS and TLS: Why Encryption Matters

Direct Answer

HTTPS (Hypertext Transfer Protocol Secure) is the secure version of HTTP. It uses TLS (Transport Layer Security) to encrypt the data sent between your browser and a website, ensuring that sensitive information—like passwords, credit card numbers, and private messages—cannot be read or stolen by anyone on the network.

Overview

Whenever you see a “Padlock” icon in your browser’s address bar, you are using HTTPS. In the past, most websites used HTTP, which sent data in plain text. This meant that your ISP, or anyone sharing your Wi-Fi, could “eavesdrop” on your activity. HTTPS encrypts this data, making it unreadable to everyone except the intended recipient.

Direct Answer

The internet is transitioning from IPv4 to IPv6 because we have run out of unique IPv4 addresses. While IPv4 supports only 4.3 billion addresses—nowhere near enough for the world’s devices—IPv6 provides a virtually infinite supply (340 undecillion). For users in Bangladesh, this transition is the long-term solution to problems like CGNAT, high gaming latency, and the need to pay extra for “Real IPs.”

Comparison at a Glance

Why the Transition is Happening

1. IPv4 Exhaustion

When IPv4 was created in the 1980s, 4.3 billion addresses seemed like plenty. However, with the explosion of smartphones, IoT devices, and global internet access, the world officially ran out of unallocated IPv4 “blocks” years ago.

ITC (International Terrestrial Cable)

Definition

An ITC (International Terrestrial Cable) is a fiber-optic cable connection that runs over land across national borders to provide international internet bandwidth. In Bangladesh, ITCs connect our national network to the global internet backbone through India.

Role in Bangladesh

Before ITCs were introduced, Bangladesh was entirely dependent on the BSCCL (now BSCPLC) submarine cables (SMW-4 and SMW-5). If those cables were cut or went under maintenance, the entire country would lose connectivity.

Mesh Wi-Fi: Coverage for Large Concrete Homes

Direct Answer

Mesh Wi-Fi is a whole-home Wi-Fi system designed to eliminate dead zones and provide uninterrupted Wi-Fi throughout your home. Unlike traditional routers and extenders, Mesh systems use multiple interconnected nodes that work together as a single network.

Overview

In a traditional setup, you have one router. As you move away from it, the signal weakens. Wi-Fi extenders can help, but they often create a separate network (e.g., Home_WiFi_EXT) and cut your speed in half. Mesh Wi-Fi replaces this with a seamless system where your devices automatically switch to the strongest node as you move between rooms, all while keeping the same network name (SSID).

Direct Answer

Ping measures the round-trip time (latency) for data to travel from your device to a server and back, while Packet Loss occurs when data units fail to reach their destination. In Bangladesh, high latency in the first three hops usually indicates local WiFi congestion or NTTN fiber faults, rather than international line issues.

Overview

For a smooth internet experience—whether gaming, video conferencing, or browsing—low latency and zero packet loss are critical. While “speed” (bandwidth) determines how much data you can download, ping determines how “responsive” that connection feels.