Networks are generally mapped with almost no knowledge, from far much away from the actual network we gather information and interpret the network topology is known as Black Box. In this case, cracker initiate with IP address of server or URL of the website of victim organization.
Ethical hacker must aware of Zone Transfer detailing, mail headers reading and some Denial of Service Attacks. From the passive information that is gathered about network is well formatted and records of zone transfers, Route Tracing by breaking mail headers and reverse lookups one can map the topology of network.
Following information gets exposed through such enumerating:
IP addresses of Web servers
IP addresses of Mail servers
IP addresses of DNS servers
Many secure networks create sub-nets their information which is also called as masking IP addresses, which reduces direct exposure of these IP addresses.
Any simple secure gateway of network can be made of following
Secondary security systems, such as IDS.
And Backup servers.
By simply examining the host and network, there are many design characteristics associated with different types of technology which makes it easier for attackers and also ethical hackers to create a perfect network map. Unobtrusive Mapping of Network gives out much information about servers and IP addresses.
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