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Security Portal: Filling Network Holes

Mar 07, 2000, 04:28 (0 Talkback[s])
(Other stories by John D. Johnson)

"Understanding Internet Protocol (IP) packets, other network protocols, and how networks communicate bring forth both the strengths and vulnerabilities of Internet use. Intruders such as hackers and insiders with questionable intentions use network scanners and packet sniffers to analyze the components of networks in order to reveal open connections on networks, through virtual ports, and find unguarded ports to exploit. They also employ spoofing (masquerading as an authorized IP address to conceal their true IP address identity) to fool a network that a message originated from a known and trusted system."

"Protocols (rules that computers use to communicate between systems and networks) are open, well documented and supported by a wide variety of applications, programs, utilities and management tools, making them both essential for network communications and exploitable avenues for intruders. The basic structure of network protocols must remain standard, documented and visible in order to support software, hardware and methods to interoperate properly. This openness required for network communication and Internet growth also leaves network structures open to be taken advantage of by those attempting to gain unauthorized access to data. This includes interception of IP packets and extraction of data such as logon user names and/or passwords within those messages."

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