The information contained in the domain name space should be stored. However, it is not efficient as well as unreliable to store information on a single computer system. Inefficient because requests for all over the world would put heavy load on a system. It is not reliable because any failiure makes the data unavailable.
DNS Servers
The solution of above problem is to distribute the information among many computers called DNS Servers. One way to do this is to divide the whole name space into many domains based on the first level. In other words, we let the root stand alone and create as many domains (subtrees) as there are first-level nodes. Because a domain created this way could be very large, DNS allows domains to be divided further into smaller domains (subdomains). Each server can be responsible (authoritative) for either a large or small domain. In other words, we have a hierarchy of servers in the same way that we have a hierarchy of names.
Zone
What a server is responsible for or has authority over it is called a zone. If a server accepts responsibility for a domain and does not divide the domain into smaller domains (subdomains), the "domain" and the 'zone" refers to the same thing. the server makes a database called a zone file and keeps all the information for every noe under that domain. However, if a server divides its domain into subdomains and delegates part of its authority to other servers, "domain" and "zone" refer to different things. The information about the nodes in the subdomains is stored in the servers at the lower levels, with the original server keeping some sort of reference to these lower-level servers. Of course the original server does not free itself from responsibility totally: It still has a zone, but the detailed information is kept by lower level servers.
A server can also dividepart of its domain and delegate responsibility but still keep part of domain for itself. In this case, its zone is made of detailed information for the part of the domain that is not delegated and references to those parts that are delegated.
Root Server
A root server is a server whose zone consists of whole tree. A root server usually does not store any information abotdomains but delegates its authority to other servers , keeping references to those servers. Currently there are more than 13 root serverscovering th whole domain space. The servers are distributed all around the world.
Primary and Secondary Servers
DNS defines two types of servers, primary and secondary. A primary server is a server taht stores the file about the zone for whih it is an authority. It is responsible for creating, maintaining, and updating the zone file. It store sthe zone file on a local disk.
A secondary server is a server that transfers the complete information about a zone from another server (primary or secondary) and stores the file on its local disk. the secondary server neither creates nor updates the zone files. If udating is required, it must be done by primary server, which sends the updated version to secondary.
The primary and secondary servers are both authoritative for the zone they serve. The idea is not to put the seconadary server at alower level of authority but to create redundancy for data so that if one server fails, the other can continue serving clients. Note also that a server can be a primary server for a specific zone and a secondary server for another zone
Zone Transfer
A primary server loads all information from the disk file; the secondary DNS Server loads all information from the primary server. When the primary DNS server downloads information from the secondary, it is called zone transfer.
Related Posts:
DNS Servers
The solution of above problem is to distribute the information among many computers called DNS Servers. One way to do this is to divide the whole name space into many domains based on the first level. In other words, we let the root stand alone and create as many domains (subtrees) as there are first-level nodes. Because a domain created this way could be very large, DNS allows domains to be divided further into smaller domains (subdomains). Each server can be responsible (authoritative) for either a large or small domain. In other words, we have a hierarchy of servers in the same way that we have a hierarchy of names.
Zone
What a server is responsible for or has authority over it is called a zone. If a server accepts responsibility for a domain and does not divide the domain into smaller domains (subdomains), the "domain" and the 'zone" refers to the same thing. the server makes a database called a zone file and keeps all the information for every noe under that domain. However, if a server divides its domain into subdomains and delegates part of its authority to other servers, "domain" and "zone" refer to different things. The information about the nodes in the subdomains is stored in the servers at the lower levels, with the original server keeping some sort of reference to these lower-level servers. Of course the original server does not free itself from responsibility totally: It still has a zone, but the detailed information is kept by lower level servers.
A server can also dividepart of its domain and delegate responsibility but still keep part of domain for itself. In this case, its zone is made of detailed information for the part of the domain that is not delegated and references to those parts that are delegated.
Root Server
A root server is a server whose zone consists of whole tree. A root server usually does not store any information abotdomains but delegates its authority to other servers , keeping references to those servers. Currently there are more than 13 root serverscovering th whole domain space. The servers are distributed all around the world.
Primary and Secondary Servers
DNS defines two types of servers, primary and secondary. A primary server is a server taht stores the file about the zone for whih it is an authority. It is responsible for creating, maintaining, and updating the zone file. It store sthe zone file on a local disk.
A secondary server is a server that transfers the complete information about a zone from another server (primary or secondary) and stores the file on its local disk. the secondary server neither creates nor updates the zone files. If udating is required, it must be done by primary server, which sends the updated version to secondary.
The primary and secondary servers are both authoritative for the zone they serve. The idea is not to put the seconadary server at alower level of authority but to create redundancy for data so that if one server fails, the other can continue serving clients. Note also that a server can be a primary server for a specific zone and a secondary server for another zone
Zone Transfer
A primary server loads all information from the disk file; the secondary DNS Server loads all information from the primary server. When the primary DNS server downloads information from the secondary, it is called zone transfer.
Related Posts:
- Domain Name Space
- DNS In The Internet
A DNS server is any computer registered to join the Domain Name System. A DNS server runs special-purpose networking software, features a public IP address, and contains a database of network names and addresses for other Internet hosts. If any queries regarding website DNS use Whoisxy.com
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DNS servers communicate with each other using private network protocols. All DNS servers are organized in a hierarchy. At the top level of the hierarchy, so-called root servers store the complete database of Internet domain names and their corresponding IP addresses.
The gamers have observed that a wrong DNS server can lower down the gaming speed and disrupt the usual functioning of a smooth gaming experience. So we have created a list of fast dns servers for ps4 to enjoy thier game hassle free.
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