Search results
Results from the WOW.Com Content Network
Google Public DNS is a Domain Name System (DNS) service offered to Internet users worldwide by Google. It functions as a recursive name server . Google Public DNS was announced on December 3, 2009, [ 1 ] in an effort described as "making the web faster and more secure."
On 16 August 2013, every Google service went down for five minutes; that is from 22:52 to 22:57 UTC. The outage caused internet traffic to drop forty percent worldwide. [9] Between 23:51 and 23:52 UTC, 50–70% of requests to Google received errors. It has been estimated that the blackout could cost Google around £330,000. [9]
Returns all records of all types known to the name server. If the name server does not have any information on the name, the request will be forwarded on. The records returned may not be complete. For example, if there is both an A and an MX for a name, but the name server has only the A record cached, only the A record will be returned.
A DNS name server is a server that stores the DNS records for a domain; a DNS name server responds with answers to queries against its database. The most common types of records stored in the DNS database are for start of authority ( SOA ), IP addresses ( A and AAAA ), SMTP mail exchangers (MX), name servers (NS), pointers for reverse DNS ...
A Domain Name System blocklist, Domain Name System-based blackhole list, Domain Name System blacklist (DNSBL) or real-time blackhole list (RBL) is a service for operation of mail servers to perform a check via a Domain Name System (DNS) query whether a sending host's IP address is blacklisted for email spam. [1]
DNS hijacking, DNS poisoning, or DNS redirection is the practice of subverting the resolution of Domain Name System (DNS) queries. [1] This can be achieved by malware that overrides a computer's TCP/IP configuration to point at a rogue DNS server under the control of an attacker, or through modifying the behaviour of a trusted DNS server so that it does not comply with internet standards.
Google, a major provider of services on the Internet, experimented with using a type of DNS allowlisting on a per-ISP basis to prevent this [9] [10] until the World IPv6 Launch. In the DNS allowlisting approach, ISPs are determined from DNS lookup source IP addresses by correlating them with network prefixes derived from routing tables .
For example, to do a reverse lookup of the IP address 8.8.4.4 the PTR record for the domain name 4.4.8.8.in-addr.arpa would be looked up, and found to point to dns.google. If the A record for dns.google in turn pointed back to 8.8.4.4 then it would be said to be forward-confirmed.