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DNS Server Configuration on CentOS 7 (Caching DNS with BIND)
DNS (Domain Name System) Server is an essential part to any computer network. Today web communication cannot imagine without DNS Server. DNS is a client server protocol where DNS Client requests for the domain name resolution and DNS Server response on it. Every network should have a DNS Server because local DNS Server improves network performance by caching DNS information and serving DNS request locally. DNS Server can be configured either Windows or Linux operating system. In this article, I will discuss how to configure a caching DNS Server on CentOS 7/ RedHat 7 Linux with BIND9 Service. Domain Name System (DNS) and How It Works Communication between a workstation (PC) and a Server are always done by IP address. So, to get any information from any Web Server, you have to remember the IP address of that Server. But remembering a huge number of public IP addresses is almost impossible for the human being. To solve this issue, DNS technique is introduced in computer networking. The DNS technique can be best compared to a phone book where a user finds a phone number listed by the easier-to-remember name. So, the DNS can be defined as a mapper between human [...]
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MikroTik Blocking Websites with TLS Host Firewall Matcher | April 29, 2019
Most of the websites now use https and blocking https websites is so much harder with the MikroTik RouterOS version less than 6.41. But from RouterOS v6.41, MikroTik Firewall introduces a new property named TLS Host that is capable to match https websites so easily. So, blocking https websites like Facebook, YouTube etc. can be easily done with MikroTik Router if RouterOS version is greater than 6.41. In my previous article, I discussed how to block websites with MikroTik Router [...]
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What Are the 7 Layers of OSI Model and How Do They Work | October 5, 2021
The OSI Model stands for Open Systems Interconnection Model, a conceptualized framework used to describe the seven layers of a telecommunication system or network. It was established as an international standard in the year 1984 by the International Organization for Standardization. This model helps visualize how networks operate and is still used today to figure out and solve network problems, such as by a web development company. In this article, we will talk about the 7 layers of the OSI [...]
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How to Separate MikroTik Hotspot and DHCP IP Pool | October 9, 2020
MikroTik default Hotspot Setup comes with a DHCP Server (which uses same IP Pool of Hotspot Server) to provide IP address and other network information to a connected device. Using this automatic IP address connected device can access Hotspot login page. After successfully login, a one to one NAT IP address is also assigned for the device and this process happens internally in Hotspot Server. User device cannot know this one to one NAT IP assigning. However, Hotspot Server actually [...]
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How to Block Free Proxy Access with MikroTik Router | May 21, 2019
Proxy Server is an alternative to VPN that breaks blocking firewall of a network. If any user uses free web proxy server with web browser, the web request is processed by the proxy server. So, blocking firewall rule is not applied on the proxy enabled PC. For this, system administrators should be careful enough to block free proxy servers along with blocking VPN access. In my previous article, I discussed how to block VPN access with MikroTik Firewall. In this [...]
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MikroTik Hotspot Auto Login by MAC Address | July 1, 2020
Hotspot is an awesome service in MikroTik Router. MikroTik Hotspot is popularly used in ISP, Hotel, Airport, Coffee Shop, Enterprise office and many other organizations. By default MikroTik Hotspot uses HTTP CHAP login method where user must provide username and password to get internet service. Sometimes we may face that some users are not eager to provide username and password to get internet service or we cannot ask some users to put username and password to get internet due to [...]
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MikroTik Hardware Redundancy with VRRP | October 8, 2018
MikroTik VRRP (Virtual Router Redundancy Protocol) ensures high availability internet network. If any organization requires uninterrupted internet connection, MikroTik VRRP implementation will be a vital solution for them. MikroTik VRRP creates a virtual router accumulating two or more physical routers and ensures uninterrupted internet connection keeping activate one physical router always. That means, if any physical router fails to operate due to any hardware failure, MikroTik VRRP uses another backup router for internet gateway until the running router comes back [...]
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How to Get Free SSL Certificate from ZeroSSL | June 13, 2020
SSL/TLS certificate is an essential part in today internet communication. Online communication cannot imagine without SSL/TLS certificate. SSL/TLS certificate makes online communication secure by encrypting data transmitted over public internet. So, most of the applications (Web, Email and VPN services) those transmit data over public internet use SSL/TLS certificate to secure communication. SSL/TLS certificate requires to be signed by Certificate Authority (CA). It is possible to create self-signed certificate with SSL certificate creation tools such as OpenSSL. Some router venders [...]
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MikroTik Hotspot Login by HTTP CHAP, HTTP PAP and HTTPS | July 25, 2020
MikroTik Hotspot uses various types of login methods. Among these login methods HTTP CHAP, HTTP PAP and HTTPS are basic and important login methods. So, a MikroTik system administrator should have proper understanding on Hotspot HTTP CHAP, HTTP PAP and HTTPS login methods. In my previous article I discussed how to configure MikroTik Hotspot using Winbox. In this article I will discuss how to use HTTP CHAP, HTTP PAP and HTTPS login methods properly in MikroTik Hotspot Server. MikroTik Hotspot [...]
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Why ISPs Should Embrace TR-069 ACS to Stay Ahead of Competitors | May 22, 2023
As the telecommunications industry becomes more competitive, local ISPs need to find ways to stay ahead of larger telcos and offer services that meet the changing demands of their customers. One of the solutions to this challenge is to implement TR-069 ACS server to help streamline network management, reduce costs, and increase efficiency. In this article, we’ll explore why the TR-069 ACS server is essential for medium-sized ISPs to stay competitive in today’s market. We’ll examine the challenges these ISPs [...]
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