The binary uses a network data encoding process identify the encoding process and develop a decoder
In other words, effects encoding sets up an array of numeric values. The size of the array is the number of possible values, c. The first categorical value has 0. The second categorical value has the single 1. The last categorical value, instead of having a 1. In the demo, the dependent variable, political affiliation, is categorical and has four possible values: In other words, 1-of-C encoding is the same as effects encoding except that that last categorical value has a 1.
Instead of having four possible values, suppose the dependent variable, political affiliation, had just two values, "conservative" or "liberal. In such situations I recommend using a simple 0. It isn't at all obvious why I recommend four different encoding schemes for the four different data cases. And there are several alternatives. You can find many online references that go into a painfully detailed discussion of this topic if you're interested in the theory behind these encoding recommendations.
Normalizing Numeric Data There are two neural network numeric data cases: An example of independent numeric data values are the ages 54, 28, 31, 48, 22, 39 in the demo program. For example, in the demo program, the mean of all six age values is So the normalized age for the first person is In most cases, normalized numeric data will have values that range between The idea behind data normalization is to scale all numeric data to have roughly similar magnitudes.
In the demo, a typical annual income value is 30, Without normalization, the large magnitudes of the income data relative to the age data would make the neural network training process more difficult than with normalized data, because changes to the income-weights would have a much greater effect than changes to the age-weights.
The only way to track down the attacker is to trace the replies from the backdoor to the client. How does the backdoor know where to send the replies to? When the attacker wishes to communicate with the backdoor she sends an init command containing 10 IP addresses, encoded with a proprietary XOR-strength encryption algorithm.
The source of the packet with the init command can be spoofed because the backdoor only uses the IP addresses inside the packet payload. Upon receiving the init command, the backdoor stores the client IP addresses. All replies are sent to all 10 client IP addresses. Only one of them needs to be the real IP address of the attacker. Looking at traffic generated by the backdoor it's impossible to the tell which address is the real one.
If a system administrator or the authorities decide to go through the logs and track down the attacker, they will get 10 possible addresses, 9 of which are completely unrelated to the incident. Many of the backdoor DDoS commands don't even send back replies and can be triggered with only one spoofed packet. There are 11 different commands that the backdoor can execute.
Each of them has a number of parameters. Here is a list of all commands and their descriptions:. The init command initializes the backdoor address list. If type is 0, only one IP address has to be specified in the ip parameter. All replies from the backdoor are sent to this IP address. If type is 1, the replies will be sent to this address and 9 other random addresses.
If type is 2, the attacker specifies 10 IP addresses and the replies are sent to all of them. The status command causes the backdoor to send a reply packet with the type of the currently running DoS or shell process. Only one such process can be started at a time and it should be kill with the kill command when it is no longer needed.
If no process is running, status return 0 idle. The kill command kills the currently running shell or DoS process. The shell command in the cmd is executed by the backdoor. Its stdout and stderr are discarded.
No reply is sent. Its stdin and stderr are captured and the output is sent to the client as reply packets. The attacker can use telnet or netcat to connect to this port. The first line sent to must match the backdoor password, otherwise the connection is terminated. The password in the binary captured by the honeynet project is "SeNiF". To kill the shell process, use the kill command. Launches a UDP flood attack.
The backdoor forks a new process which sends the packets. To stop the attack, use the kill command to kill this process the same applies to all DoS attacks available in the backdoor.
The victim can be specified with the dst or hostname parameters. If a hostname is used it is resolved again after every packets have been sent, in case the dns record of the victim has changed.
The source of the packets can be spoofed with the src parameter. A variation of this attack is the ICMP smurf attack. If the attacker sends spoofed ICMP echo requests to the broadcast address of a vulnerable network, all hosts on the network will send their responses to the victim. The entire network will act as a traffic amplifier for the attack.
This kind of attack was first reported by Edward Henigin in It is possible to use the backdoor a tool for a ICMP smurf attack, but we'll have to use the IP address of the victim, because the author of the backdoor did not include support for resolving the source IP address of the packet. Launches a SYN flood attack. A good description of the SYN flood atack is the Phrack 48 article by route.
The victim is specified with the dst or the hostname parameters. The source ip address can be specified with src or left empty, in which case a random address is generated for each packet. It should be an open TCP port on the victim's system. If the parameter is not specified, the process sleeps after each packet.
The oldest code of all, originally employed in the landline telegraph during the 19th century, is the Morse code. The terms encoding and decoding are often used in reference to the processes of analog-to-digital conversion and digital-to-analog conversion. In this sense, these terms can apply to any form of data, including text, images, audio, video, multimedia, computer programs, or signals in sensors, telemetry, and control systems.
Encoding should not be confused with encryption , a process in which data is deliberately altered so as to conceal its content. Encryption can be done without changing the particular code that the content is in, and encoding can be done without deliberately concealing the content. How to address automated networking strategically. How to prevent network downtime in the modern enterprise. By submitting you agree to receive email from TechTarget and its partners.
If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. CORD architecture offers service providers a compelling way to combine open hardware and software in the central office, boost The future of SDN could show variations of the technology becoming more prominent among enterprises, as organizations look Figuring out how to calculate bandwidth requirements is vital to ensuring your network runs smoothly, and it's best to get the Learn about the different types of noise in data communication -- including thermal, intermodulation, cross-talk, impulse and This slideshow highlights the best VPNs used in enterprise wide-area networks WANs and offers principles for designing and UC deployment has evolved, and enterprises can now choose from on-premises or cloud-based UC options or a mix of both.
A new Google text-to-speech service generates natural-sounding speech in 32 voices and 12 languages. Developers can integrate the Instant apps are bite-size applications that end users don't need to install to their mobile devices.
Discover the pros and cons With so many mobile users reliant on Office to get work done, it was high time Microsoft and EMM vendors made app management AI technology is growing fast, and end-user computing administrators need to be prepared for the multitude of benefits it can Interxion's Dublin-based data center business continues to grow as an increasing number of American and European companies see Organizations don't necessarily have to decide between using a public or private cloud.
For some companies, the answer is both. An Azure debugging tool gives admins a better handle on problems when VMs don't boot properly, with a familiar feel for those