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Traffic Shaping, Bandwidth Shaping, Packet Shaping with Linux tc htb

Denial of service attacks are major nuisance for web hosts, and as a web host you'll have to take every measure to protect your resources from DoS attacks. Our APF, BFD, DDoS and RootKit article describes Linux utilities available to protect from DDoS attack, and also explains installation procedures. This article supplements above article by providing means to control traffic (bandwidth shaping) with Linux "tc" command so that no single machine can waste the entire network bandwidth.


Denial of Service (DoS) and DDoS Attacks

DoS attack, denial-of-service attack, is an explicit attempt to make a computer resource unavailable by either injecting a computer virus or flooding the network with useless traffic. In simple words, it is similar to thousands of people trying to enter a room from a single entrance, ultimately causing havoc. This not only disturbs the normal operations of the network but also results in poor performance and system breakdown due to overwhelming requests. A large-scale DDoS attack (ranges up to 400 GBps) can affect the internet connectivity of an entire geographical region. There are two types of DoS attacks: computer attack and network attack. Common forms of denial of services attacks are:

How do I change a web host without downtime?

Changing a web host is nuisance, but there is no reason to tolerate less then optimum service from your current web host if you're not happy with them. If you plan ahead, changing a web host may not be too bad and can be done without downtime or email disruptions. The most important thing to note is not to cancel your existing account until you're done. Even if you hate your current hosting provider, it's essential that you keep your account active until the transfer is complete. Cancelling the account ahead of time will make the transition difficult.

How do I find a good web host?

When searching for a reliable web host, consider factors like server uptime, loading speed, customer support, scalability, security features, and pricing. Ensure the host aligns with your website's needs, whether it's a personal blog or e-commerce site, and check for user reviews and recommendations to gauge their reputation.


What is IP Spoofing and how to avoid it?

IP Spoofing is a technique used to gain unauthorized access to machines, whereby an attacker illicitly impersonates another machine by manipulating IP packets. IP Spoofing involves modifying the packet header with a forged (spoofed) source IP address, a checksum, and the order value. Internet is a packet switched network, which causes the packets leaving one machine may be arriving at the destination machine in different order. The receiving machine resembles the message based on the order value embedded in the IP header. IP spoofing involves solving the algorithm that is used to select the order sent values, and to modify them correctly.

MS-DOS Ipconfig Command Reference

Ipconfig is a MS-DOS command-line tool used to display and manage the network settings of your computer. Ipconfig is available on Windows machines, and it displays the current network connection details and DHCP client settings.

What is a proxy server?

A Proxy server is a computer that sits between a client computer and the Internet and provides indirect network services to a client. A proxy server intercepts all client requests and provides responses from its cache or forwards the request to the real server.


What is DHCP?

The Dynamic Host Configuration Protocol (DHCP) is a network protocol that functions at the application layer of the Internet Protocol (IP) suite. A server that uses DHCP will be able to dynamically assign IP Addresses and other network configuration parameters to devices on the network; thus, allowing communication to a second network. The protocol can be implemented in networks of any size, ranging from small home area networks (HANs) to large campus area networks (CANs) and even the networks used by Internet Service Providers (ISPs).