ZyXEL Communications 320W User Manual

 

All contents copyright (c) 2005 ZyXEL Communications Corporation.   

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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 address, known as the 'victim' 

network. This flood of broadcast traffic consumes all available bandwidth, making communications 

impossible.  

Many DoS attacks also use IP Spoofing as part of their attack. IP Spoofing may be used to break into 

systems, to hide the hacker's identity, or to magnify the effect of the DoS attack. IP Spoofing is a 

technique used to gain unauthorized access to computers by tricking a router or firewall into thinking that 

the communications are coming from within the trusted network. To engage in IP Spoofing, a hacker 

must modify the packet headers so that it appears that the packets originate from a trusted host and should 

be allowed through the router or firewall.   

 

 

 

Wireless FAQ 

 

Wireless LANs provide all the functionality of wired LANs, without the need for physical connections 

(wires). Data is modulated onto a radio frequency carrier and transmitted through the ether. Typical 

bit-rates are 11Mbps and 54Mbps, although in practice data throughput is half of this. Wireless LANs can 

be formed simply by equipping PC's with wireless NICs.   If connectivity to a wired LAN is required an 

Access Point (AP) is used as a bridging device. AP's are typically located close to the centre of the 

wireless client population.   

a. Mobility: 

Wireless LAN systems can provide LAN users with access to real-time information anywhere in their 

organization. This mobility supports productivity and service opportunities not possible with wired 

networks.   

b. Installation Speed and Simplicity: 

Installing a wireless LAN system can be fast and easy and can eliminate the need to pull cable through 

walls and ceilings.