Info about Domain Names
What is Name Space? Explain with example.
The term namespace can be thought of as "the space of all names" for the particular type of network naming system under consideration. A simple example is Internet Protocol (IP) address space, the space of all possible IP addresses. This space is divided into class A, class B, and so on, which represent disjoint subgroups of the IP address space. Generally, every node on a Transmission Control Protocol/Internet Protocol (TCP/IP) network, internetwork, or the Internet must occupy a unique point in IP address space-that is, it must have a unique IP address. This ensures that a packet addressed to a particular node (such as a computer, network printer, or router interface) can be directed to the node using its IP address as the destination address. If two nodes on a network were to have the same IP address number, a packet intended for one might end up at the other. One exception to this is multicasting, in which a packet is sent to a group of hosts simultaneously and ignored by all other hosts. Another exception is when you have a private network connected to the Internet through a firewall that uses network address translation (NAT) to hide the addresses of hosts on the private network from hosts on the Internet. In this case, if no direct communication is expected between nodes in the two networks (except through the firewall), nodes in the private network can be assigned arbitrary IP addresses, such as 10.x.y.z , and two or more private networks can use the same addressing scheme without fear of confusion or lost packets.
An example of a namespace is the hierarchy of distinguished names (DNs) used to identify objects in a directory based on the Lightweight Directory Access Protocol (LDAP). The LDAP namespace is closely tied to the DNS namespace of the Internet, as the top-level LDAP containers are simply top-level domain names. The Active Directory directory service of Windows 2000 is based on LDAP and uses DNs to name objects stored within its directory.