NetComm NB712 manual Ping of death, SYN Flood, Icmp Flood, UDP Flood, Land attack, Smurf attack

Ping of death	On the Internet, ping of death is a kind of denial of service
	(DoS) attack caused by an attacker deliberately sending an
	IP packet larger than the 65,536 bytes allowed by the IP
	protocol. One of the features of TCP/IP is fragmentation; it
	allows a single IP packet to be broken down into smaller
	segments. Attackers began to take advantage of that feature
	when they found that a packet broken down into fragments
	could add up to more than the allowed 65,536 bytes.
	Many operating systems didn’t know what to do when they
	received an oversized packet, so they froze, crashed, or
	rebooted. Other known variants of the ping of death include
	teardrop, bonk and nestea.
SYN Flood	The attacker sends TCP connections faster than the
	victim machine can process them, causing it to run out
	of resources and dropping legitimate connections. A new
	defence against this is to create “SYN cookies”. Each side
	of a connection has its own sequence number. In response
	to a SYN, the attacked machine creates a special sequence
	number that is a “cookie” of the connection and forgets
	everything it knows about the connection. It can then
	recreate the forgotten information about the connection
	where the next packets come in from a legitimate
	connection.
ICMP Flood	The attacker transmits a volume of ICMP request packets to
	cause all CPU resources to be consumed serving the phony
	requests.
UDP Flood	The attacker transmits a volume of requests for UDP
	diagnostic services which cause all CPU resources to be
	consumed serving the phony requests.
Land attack	The attacker attempts to slow your network down by sending
	a packet with identical source and destination addresses
	originating from your network.
Smurf attack	Where the source address of a broadcast ping is forged so
	that a huge number of machines respond back to the victim
	indicated by the address, thereby overloading it.
Fraggle Attack	A perpetrator sends a large amount of UDP echo packets
	at IP broadcast addresses, all of it having a spoofed source
	address of a victim.
IP Spoofing	IP Spoofing is a method of masking the identity of an
	intrusion by making it appear that the traffic came from a
	different computer. This is used by intruders to keep their
	anonymity and can be used in a Denial of Service attack.

NB712 /	NB714 User Guide	11
YML829	Rev1