Editing Denial-of-service attack (section)

===Internet Control Message Protocol (ICMP) flood===
A [[smurf attack]] relies on misconfigured network devices that allow packets to be sent to all computer hosts on a particular network via the [[broadcast address]] of the network, rather than a specific machine. The attacker will send large numbers of [[Internet Protocol|IP]] packets with the source address faked to appear to be the address of the victim.<ref>{{Cite journal |last=Sun |first=Fei Xian |date=2011 |title=Danger Theory Based Risk Evaluation Model for Smurf Attacks |url=https://www.scientific.net/KEM.467-469.515 |journal=Key Engineering Materials |language=en |volume=467-469 |pages=515–521 |doi=10.4028/www.scientific.net/KEM.467-469.515 |s2cid=110045205 |issn=1662-9795}}</ref> Most devices on a network will, by default, respond to this by sending a reply to the source IP address. If the number of machines on the network that receive and respond to these packets is very large, the victim's computer will be flooded with traffic. This overloads the victim's computer and can even make it unusable during such an attack.<ref name="ANML-DDoS">{{cite web|url=http://anml.iu.edu/ddos/types.html|title=Types of DDoS Attacks |publisher=Advanced Networking Management Lab (ANML) |work=Distributed Denial of Service Attacks(DDoS) Resources, Pervasive Technology Labs at Indiana University |date=December 3, 2009 |archive-url=https://web.archive.org/web/20100914222536/http://anml.iu.edu/ddos/types.html |archive-date=2010-09-14 |access-date=December 11, 2013 }}</ref>

[[Ping flood]] is based on sending the victim an overwhelming number of [[ping (networking utility)|ping]] packets, usually using the ''ping'' command from [[Unix-like]] hosts.{{Efn|The -t flag on [[Microsoft Windows|Windows]] systems is much less capable of overwhelming a target, also the -l (size) flag does not allow sent packet size greater than 65500 in Windows.}} It is very simple to launch, the primary requirement being access to greater [[bandwidth (computing)|bandwidth]] than the victim. [[Ping of death]] is based on sending the victim a malformed ping packet, which will lead to a system crash on a vulnerable system. The [[BlackNurse (Computer Security)|BlackNurse]] attack is an example of an attack taking advantage of the required Destination Port Unreachable ICMP packets.