Reverse Domain Name System (DNS) Lookup

Reverse Domain Name System (DNS) Lookup refers to the reverse of what happens in a Domain Name System (DNS) Lookup. To elaborate, the DNS or hostname is queried to get the corresponding IP address in Domain Name System (DNS) lookup. The opposite of this happens in Reverse Domain Name System (DNS) lookup, where the IP address is queried to find the hostname.

Domain Name System (DNS)

Domain Name System’s abbreviation is DNS. It refers to a hierarchical and decentralized nomenclature of computers, services or other resources that are connected to either the Internet or to a private network. The DNS delegates the task that assigns domain names and maps those to Internet resources. It translates domain names that are more easily memorized, to numerical IP addresses. These IP addresses are used to locate and identify computer services and devices. The DNS specifies the technical functionality of the service related to a database. A DNS database stores most commonly the following types of records, IP addresses (A and AAAA), Start of Authority (SOA), name servers (NS), SMTP mail exchangers (MX), domain name aliases (CNAME) and pointers for reverse DNS lookups (PTR). The Reverse DNS records are stored in a PTR record which is a type of a DNS record. A pointer (PTR) record aids in resolving an IP address to a hostname.

In the context of the Internet, the first thing that comes to mind are the various websites that we browse on the Internet. These websites are accessible due to the server space and the services that are provided by web hosting companies, through the wide range of paid packages that these offer. There are different types of hosting services that are provided by web hosts. These are shared, dedicated, cloud, VPS, reseller and WordPress. When terms such as, “Windows Shared Hosting” or “Linux Dedicated Hosting” or even the “Best Linux Web Hosting in India” are used, these refer to various types of web hosting services.

What are the Uses of Reverse Domain Name System (DNS) Lookup?

Reverse Domain Name System (DNS) Lookup is advantageous in many situations. These will be touched upon as we progress. The first use that needs to be mentioned is how Reverse Domain Name System (DNS) Lookup aids in finding spam emails. It is challenging to discern licit mail servers from spam servers with the aid of nothing more than the IP addresses. Potential clues are provided by certain generic Reverse Domain Name System (DNS) names for a mail server that is spam. This is one of the many ways in which the Reverse Domain Name System (DNS) Lookup can come in handy.

It also helps in acquiring information about the visitors of a particular website. IP addresses are usually maintained in the website visit logs. Reverse Domain Name System (DNS) Lookup can be used for finding the hostname of the visitors of any website. This can prove to be very advantageous for businesses.

It is extremely useful with regard to one’s outgoing emails when one is hosting one’s own email server. With the help of Reverse DNS record the origin of an email can be traced. This adds to the email server’s credibility. Often incoming emails are not granted entry in the email boxes of certain incoming email servers unless one has Reverse DNS record set up. This is an important point to bear in mind, if one is using one’s own mail server.

Last but not the least, Reverse Domain Name System (DNS) Lookup can prove to be very beneficial when a cybercrime investigation is being carried out. Moreover, Reverse DNS records can help to identify potential dangers that lurk in the cyberspace.

Final Thoughts

Reverse DNS Lookup, which is essentially the opposite of a traditional DNS Lookup, queries DNS servers for a PTR (pointer) record. It proves to be very useful in many ways and for various purposes, as is evident from all the information that has been provided here.