How to remove duplicate queries on Google DNS

[Santiaago]

What are the ways to remove duplicate queries online. I have to work on the data inter generation part of my site which is going to moved to a new server. So this need a lot of work. Also I need some best tips to remove the duplicate queries. The other thing which I am trying to to is rate the limited number of queries.

[Jackson2]

DNS resolvers are susceptible to "birthday attacks", so called for the reason that they misuse the mathematical "birthday paradox", in which the probability of a competition does not necessitate a huge amount of inputs. Birthday attacks include flooding the victim server not merely with forged answers but also with preliminary queries, counting on the resolver to problem multiple requests for a single name resolution.

[Techno01]

The bigger the amount of problem outgoing requests, the bigger the possibility that the invader will competition one of those requests with a forged replies or answers: an invader only requirements on the order of 300 in-flight demand for a 50% success opportunity at matching a forged replies or answer, and 700 requests for secure to 100% success. To guard against this attack approach, you be supposed to be sure to discard all duplicate queries from the outbound get in line. For illustration, Google Public DNS never permits more than a single outstanding demand for the similar query name, query type, and destination IP address.

[Trio]

Protecting denial-of-service attacks poses more than a few specific challenges for open recursive DNS resolvers: Open recursive resolvers are striking objectives for introduction of an intensification attacks. They are high-capability, high-dependability servers and can generate huge responses than a characteristic dependable nameserver — particularly if an attacker can inject a huge response into their accumulation. It is incumbent on any developer of an open DNS service to protect their servers from being used to commence attacks on other systems.

[deveritt]

Amplification assault can be complicated to remove while they are happening. Attackers can commence an assault via thousands of open resolvers, so that every resolver only sees a diminutive portion of the overall query volume and cannot obtain a clear signal that it has been negotiation. Malevolent traffic must be barren without any disturbance or degration of the DNS service to regular users. DNS is an important network service, so you have to turn off the servers to cut off an attack is not an alternative, nor is denying service to any given client IP for too long. Resolvers must be capable to fast block an attack as soon as it starts, and reinstate fully operational service as soon as the attack ends.

[Techguru01]

The most excellent method for struggle DoS attacks is to impress a rate-limiting or "throttling" apparatus. Google Public DNS put into practice two kinds of rate control: Rate control of outgoing demands to additional nameservers. To prevent additional DNS nameservers from the DoS attacks you can be commence from our resolver servers, Google Public DNS enforces per-nameserver QPS restrictions on outgoing requests from every serving cluster. Rate control of outgoing reactions to clients. To prevent any additional systems against amplification and traditional disseminated DoS (botnet) attacks that could be commenced from our resolver servers.