How can an organization defend itself from DoS attacks?

Distributed denial-of-service attacks can paralyze even the most well-structured network for days, costing millions of dollars in lost sales to a company. The IT department and Administrators of the server needs to prevent a DOS to save the company money. There are different strategies to minimize and even prevent a denial of service attack.  First, a micro block could be installed in the server. A micro block works by simply giving a micro-record instead of a complete connection to the user. It will only allocate a small amount, making it almost impossible to overflow the system. Second, SYN Cookies could be used in the servers.  SYN Cookies is method of using cookies to communicate with the user before making a connection.  The server will send an acknowledgement signal to see if it will have a respond. If the server gets a respond then the user is legitimate. Finally, Stack Tweaking can be used in TCP. Stack Tweaking involves altering the TCP stack on the server so that it will take less time to timeout when a SYN connection is left incomplete. It makes it almost impossible for a DOS attack to happen.