![]() ![]() Root NS then responds with the respective NS address. ![]() browser asks the DNS root NS for resolution of top level domain i.e. Suppose the user is requesting a resource named so in the figure we can see that first the end user client i.e. The below figure outlines how double flux networks actually work and how they are different from single flux networks.įirst let’s just revise how the single flux networks work. Both the DNS A record sets and the authoritative NS records for a malicious domain are continually changed in a round robin manner and advertised into the Fast Flux service network. ![]() For example, along with DNS and HTTP services, it also includes services such as SMTP, IMAP, POP, etc.ĭouble flux networks: These networks are characterized by multiple nodes registering and deregistering as a part of DNS NS records. Because Fast Flux techniques utilize blind TCP and UDP redirects, any directional service protocol with a single target port would likely encounter few problems being served via a Fast Flux service network. Single flux service networks change the DNS records for their front end node IP address as often as every 3-10 minutes, so even if one flux-agent redirector node is shut down, many other infected redirector hosts are standing by and available to quickly take its place. The request thus gets redirected to the target website. For example, the below figure shows that the victim request for and the browser are actually communicating with the flux network. For example, in the figure below we can see that in the case of normal client server communication, a normal end user agent like a web browser requests the server and the server fulfils the request of the client, whereas in a single flux network, the end user agent like a web browser communication with the server is proxied via a redirector normally called a flux-bot. Single flux networks: These are networks in which a set of compromised nodes register and deregister their address as a part of DNS address record list for a single DNS name. Types of Flux Networksįast Flux networks are classified under 2 major categories: They often use a load-distribution scheme which takes into account node health-check results, so that unresponsive nodes are taken out of flux and content availability is always maintained. In addition, the attackers ensure that the compromised systems they are using to host their scams have the best possible bandwidth and service availability. Essentially, the domain names and URLs for advertised content no longer resolve to the IP address of a specific server, but instead fluctuate amongst many front end redirectors or proxies, which then in turn forward content to another group of backend servers. Instead, compromised front end systems are merely deployed as redirectors called as flux agents funnel requests and data to and from other backend servers, which actually serve the content. The large pool of rotating IP addresses are not the final destination of the request for the content. browser connecting to the same website every 3 minutes would actually be connecting to a different infected computer each time. Website hostnames may be associated with a new set of IP addresses as often as every 3 minutes, which means that the end user client i.e. These IP addresses are swapped in and out of flux with extreme frequency, using a combination of round-robin IP addresses and a very short Time-To-Live (TTL) for any given particular DNS Resource Record (RR). All rights reserved.The basic idea behind Fast Flux is to have numerous IP addresses associated with a single fully qualified domain name, where the IP addresses are swapped in and out with extremely high frequency through changing DNS records. Published by Houghton Mifflin Harcourt Publishing Company. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. The American Heritage® Student Science Dictionary, Second Edition.
0 Comments
Leave a Reply. |