Security Problem/Threat

security is a major concern of  all the administrator sitting in their cabin.There r various ways through which network based threat or problem exist.Here I will discuss about some of them in short to give u some idea......

Man-in-the-middle-attack
In this,when a user (taking u as example ) communicate with any other user over the net than there is a possibility of someone listening/sniffing your  data packets which u r sending to your friends.This attacker will come in between u & your  friend.but u won't be able to identify this.whatever communication u do it will be with the attacker.

phishing attack
This sort of attack r generally performed by sending email on behalf of any organization generally from banks.the email appears to be legitimate to a normal user.This mail will most probably ask u  to send certain information normally your user name & password . & the reason for asking such detail may be like Some of our records have been deleted,sorry for inconvenience or it can be any other reason.if u ever get such mails,immediately contact your bank or go directly to your bank site & never open the link given in your mail to visit your bank site.