A CHAPTER 17 NETWORK MANAGEMENT 17-4 TYPES OF THREATS Security threats to a network can be divided into those that involve some sort of unauthorized access and all others www.gxmu.edu.cn
17-4 TYPES OF THREATS Security threats to a network can be divided into those that involve some sort of unauthorized access and all others. www.gxmu.edu.cn CHAPTER 17 NETWORK MANAGEMENT
A CHAPTER 17 NETWORK MANAGEMENT 17-4 5 type of security threats 5 types of security threats to a network are eavesdropping altering message contents Masquerading denial of service planting viruses or worms Eavesdropping: monitor network traffic Altering message contents Masquerading www.gxmu.edu.cn
17-4 5 type of security threats 5 types of security threats to a network are •eavesdropping •altering message contents •Masquerading •denial of service •planting viruses or worms. Eavesdropping: monitor network traffic Altering message contents Masquerading www.gxmu.edu.cn CHAPTER 17 NETWORK MANAGEMENT
A CHAPTER 17 NETWORK MANAGEMENT 17-4 Denial of service(Dos) Attacker System in esten in Systen in System in System in CA NY England Frar Tokyo Victim www.gxmu.edu.cn
17-4 Denial of service (DoS) DoS occurs when someone floods a site with messages faster than they can be handled Distributed Denial of Service, DDoS TCP DoS attack UDP DoS attack SYN flood attack UDP Flood DoS attack Land attack ICMP DoS attack Teardrop attack Ping of Death www.gxmu.edu.cn DDoS CHAPTER 17 NETWORK MANAGEMENT
CHAPTER 17 NETWORK MANAGEMENT 17-4 Dos- Syn Flooding Three-way Handshake A yn 否眼 ack www.gxmu.edu.cn
17-4 DoS - Syn Flooding www.gxmu.edu.cn Three-way Handshake A syn B ack ack, syn CHAPTER 17 NETWORK MANAGEMENT
CHAPTER 17 NETWORK MANAGEMENT 17-4 Planting viruses The most common ways Through an attachment to an e-mail By downloading software containing a virus 中李的网站主 机 水带TP病毒指令 Router 有安装防毒软 件的用户机 www.gxmu.edu.cn
17-4 Planting viruses The most common ways: Through an attachment to an e-mail By downloading software containing a virus. www.gxmu.edu.cn 有安装防毒软 件的用户机 Internet /HTTP 中毒的网站主 机 网页夹带HTTP病毒指令 CHAPTER 17 NETWORK MANAGEMENT