What Is Ping Of Death Attack; What Is Teardrop Attack; What Is Syn Flood Attack; What Is Land Attack - ZyXEL Communications P-660R-T1 Support Notes

P-660 series Support Notes
4. IP Spoofing

7. What is Ping of Death attack?

Ping of Death uses a 'PING' utility to create an IP packet that exceeds the maximum
65535 bytes of data allowed by the IP specification. The oversize packet is then sent
to an unsuspecting system. Systems may crash, hang, or reboot.

8. What is Teardrop attack?

Teardrop attack exploits weakness in the reassemble of the IP packet fragments. As
data is transmitted through a network, IP packets are often broken up into smaller
chunks. Each fragment looks like the original packet except that it contains an offset
field. The Teardrop program creates a series of IP fragments with overlapping offset
fields. When these fragments are reassembled at the destination, some systems will
crash, hang, or reboot.

9. What is SYN Flood attack?

SYN attack floods a targeted system with a series of SYN packets. Each packet
causes the targeted system to issue a SYN-ACK response, While the targeted system
waits for the ACK that follows the SYN-ACK, it queues up all outstanding
SYN-ACK responses on what is known as a backlog queue. SYN-ACKs are moved
off the queue only when an ACK comes back or when an internal timer (which is set a
relatively long intervals) terminates the TCP three-way handshake. Once the queue is
full, the system will ignore all incoming SYN requests, making the system
unavailable for legitimate users.

10. What is LAND attack?

In a LAN attack, hackers flood SYN packets to the network with a spoofed source IP
address of the targeted system. This makes it appear as if the host computer sent the
packets to itself, making the system unavailable while the target system tries to
respond to itself.

11 What is Brute-force attack?

A Brute-force attack, such as 'Smurf' attack, targets a feature in the IP specification
known as directed or subnet broadcasting, to quickly flood the target network with
useless data. A Smurf hacker flood a destination IP address of each packet is the
broadcast address of the network, the router will broadcast the ICMP echo request
packet to all hosts on the network. If there are numerous hosts, this will create a large
amount of ICMP echo request packet, the resulting ICMP traffic will not only clog up
the 'intermediary' network, but will also congest the network of the spoofed source IP
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