Spam is usually sent in bulk. A bulk mailing consists of many copies of the same original spam message, each sent to a different recipient. The copies are usually obfuscated, i.e. modified a bit in order to look different from each other. In collaborative spam filtering it is important to determine which emails belong to the same bulk. This allows, after observing an initial portion of a bulk, ...

Spam doesn't really need an introduction—anyone who owns an email address likely receives spam emails every day. However, spam is much more than just an annoyance. Spam's hidden economic cost for companies in wasted storage, bandwidth, technical support, and most important, the loss of employee productivity, is astronomical. The annual cost of spam for a company with 12,000 employees is approxi...

To circumvent spam filters, many spammers attempt to obfuscate their emails by deliberately misspelling words or introducing other errors into the text. For example viagra may be written vigra, or mortgage written m0rt gage. Even though humans have little difficulty reading obfuscated emails, most content-based filters are unable to recognize these obfuscated spam words. In this paper, we prese...

Spam has become an important problem for computer security because it is a channel for spreading threats, including computer viruses, worms and phishing. Currently, more than 85% of received emails are spam. Historical approaches to combating these messages, including simple techniques such as sender blacklisting or using email signatures, are no longer completely reliable on their own. Many so...

We provide an automated graph theoretic method for identifying individual users’ trusted networks of friends in cyberspace. We routinely use our social networks to judge the trustworthiness of outsiders, i.e., to decide where to buy our next car, or to find a good mechanic for it. In this work, we show that an email user may similarly use his email network, constructed solely from sender and re...

Nowadays most of Internet users surfer from spam emails. Filtering technique is one of the effective methods which help us to get rid of the spam emails. One of the problems of filtering is that it cannot detect spam emails accurately when the concepts change or drift happens as time goes by. Therefore, it is required to handle concept drift accurately and quickly. This paper proposes a new alg...

Unsolicited emails, known as spam, are one of the fast growing and costly problems associated with the Internet today. Among the many proposed solutions, a technique using Bayesian filtering is considered as the most effective weapon against spam. Bayesian filtering works by evaluating the probability of different words appearing in legitimate and spam mails and then classifying them based on t...

Unsolicited emails, known as spam, are one of the fast growing and costly problems associated with the Internet today. Among the many proposed solutions, a technique using Bayesian filtering is considered as the most effective weapon against spam. Bayesian filtering works by evaluating the probability of different words appearing in legitimate and spam mails and then classifying them based on t...

Email spam is a word that we come across in our daily life. The word spam means junk mails. The unsolicited emails that are received by any person in his/her mailbox are called spam. These junk mails are usually sent in bulk for advertising and marketing some products. This work presents a neural network approach to intrusion detection. A Multi-Layer Perceptron using Back Propagation Algorithm ...