What is the function of a domain name server? After reading it, you will understand it all

in the huge system of the Internet, we access various websites and APPs through domain names every day, but few people pay attention to the core support behind it. As the invisible "translator" and "navigator" of the online world, the domain name server silently assumes the key role of connection and is an important infrastructure to ensure smooth and safe network access. This article will dismantle the role of the domain name server for you from multiple core dimensions, and take you to see the operation logic behind Internet access.

, the role of the name server is the basic support of network access?

to understand the access logic of the Internet, we must first clarify the correspondence between the domain name and the Internet Protocol Address, which is also the most basic embodiment of the role of the domain name server.

1 Translation of Domain Name and Internet Protocol Address

devices in the Internet are identified and communicated through the Internet Protocol Address, but the pure digital Internet Protocol Address is difficult to remember, so the domain name came into being. The function of the domain name server is to store the mapping relationship between the domain name and the corresponding Internet Protocol Address. When the user enters the domain name to initiate an access request, the domain name server will quickly query and return the corresponding Internet Protocol Address, so that the user's device can accurately find the target server and complete the first step of access.

2, build a hierarchical domain name resolution system

domain name system is a hierarchical structure, from the root domain name server to the top-level domain server, and then to the authoritative domain name server, forming a complete chain of resolution. The role of the domain name server is to perform their duties in this chain. The root domain name server manages the records of the top-level domain, the authoritative domain name server stores the IP mapping of the specific domain name, and the recursive domain name server is responsible for completing the whole process query from the root to the authority for the user to ensure that the resolution request can be responded to efficiently and accurately.

2, the role of the name server includes load balancing and fault tolerance?

In addition to the basic resolution function, the role of the domain name server also extends to the stability of the network service level, especially for high-traffic platforms.

1, intelligent load balancing

when a domain name corresponds to multiple servers, the function of the domain name server is to assign the user's access request to different servers according to the preset policy. For example, according to the real-time load of the server, the user's geographical location and other factors, the request is directed to the server with less pressure and closer distance, which can not only avoid the overload and collapse of a single server, but also improve the user's access speed, so that the service capacity of large platforms can be fully released.

2, provide automatic switching of failed servers

when the server fails and cannot respond normally, the role of the domain name server is reflected in fault tolerance. By monitoring the running status of the server in real time, the domain name server will automatically remove the Internet Protocol Address of the failed server from the mapping list, and direct subsequent access requests to the normal running server to ensure that the user's access will not be interrupted due to the failure of a single server, which improves the availability of network services.

Third, the role of the domain name server involves security protection and rights management?

in today's increasingly prominent cyber security issues, the role of domain name servers is no longer limited to resolution and scheduling, but also bears important security protection and authority control responsibilities.

1, defend against domain name hijacking and phishing attacks

domain name hijacking is a common means of network attacks. Attackers guide users to malicious servers by tampering with domain name resolution records. The function of domain name servers is to add digital signatures to parse records through security protocols such as DNSSEC to ensure that the Internet Protocol Address obtained by users is real and effective to avoid malicious tampering. At the same time, domain name servers can also intercept known phishing domains through blacklist mechanisms to protect user information security.

2, control access to domain names

for the internal network of the enterprise, the role of the domain name server also includes the management of access rights. Administrators can set access rules through the domain name server, restrict internal users' access to certain domain names, or only allow specific devices to access designated servers through domain names, which can not only ensure the security of the internal network, but also avoid irrelevant traffic occupying network resources.

4, the role of the name server is to optimize the network access experience?

In addition to the support of the functional level, the role of the domain name server is also reflected in improving the user's network access experience, making the entire access process smoother and more efficient.

1, through the cache mechanism to accelerate the parsing speed

domain name server is to store the cache of resolution records. When multiple users request the same domain name, the domain name server can directly return the Internet Protocol Address in the cache without initiating the whole process of resolution query again, which greatly shortens the resolution time and improves the response speed of access. The valid period of the cache can be set according to the update frequency of the domain name, which not only ensures the efficiency, but also takes into account the accuracy of the record.

2, intelligent scheduling to improve cross-regional access speed

for platforms with global server nodes, the role of the domain name server is to direct access requests to the nearest server node according to the user's geographical location. For example, when a Chinese user visits an international website, the domain name server will automatically return the Internet Protocol Address of the domestic node, so that the user's access data does not need to be transmitted across oceans, greatly reducing network latency and improving the speed of page loading and data transmission.

To sum up, the role of the domain name server runs through the whole process of network access, from basic address translation to traffic scheduling, from security protection to experience optimization, which are indispensable core supports in the Internet system. Understanding the role of the domain name server can not only help us see the underlying logic of network access, but also allow us to more clearly understand the technical guarantee behind the stable operation of the Internet, and provide us with a cognitive basis for using the network more safely and efficiently.