Chapter 10 Firewalls
159
Nortel Business Secure Router 252 Configuration — Basics
Figure 47
SYN flood
In a LAND Attack, hackers flood SYN packets into 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.
3
A brute force attack, such as a 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 floods a router with Internet
Control Message Protocol (ICMP) echo request packets (pings). Since the
destination IP address of each packet is the broadcast address of the network,
the router broadcasts the ICMP echo request packet to all hosts on the
network. If there are numerous hosts, this creates a large amount of ICMP
echo request and response traffic. If a hacker chooses to spoof the source IP
address of the ICMP echo request packet, the resulting ICMP traffic not only
clogs up the intermediary network, but also congests 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.
Summary of Contents for BSR252
Page 28: ...28 Tables NN47923 500 ...
Page 44: ...44 Chapter 1 Getting to know your Business Secure Router NN47923 500 ...
Page 52: ...52 Chapter 2 Introducing the WebGUI NN47923 500 ...
Page 70: ...70 Chapter 3 Wizard setup NN47923 500 ...
Page 96: ...96 Chapter 5 System screens NN47923 500 ...
Page 114: ...114 Chapter 7 WAN screens NN47923 500 Figure 27 WAN IP ...
Page 120: ...120 Chapter 7 WAN screens NN47923 500 Figure 31 Dial Backup Setup ...
Page 128: ...128 Chapter 7 WAN screens NN47923 500 ...
Page 152: ...152 Chapter 9 Static Route screens NN47923 500 ...
Page 194: ...194 Chapter 11 Firewall screens NN47923 500 ...
Page 210: ...210 Chapter 13 VPN NN47923 500 Figure 67 Summary IP Policies ...
Page 222: ...222 Chapter 13 VPN NN47923 500 Figure 71 VPN Branch Office rule setup ...
Page 256: ...256 Chapter 13 VPN NN47923 500 Figure 81 VPN Client Termination advanced ...
Page 260: ...260 Chapter 13 VPN NN47923 500 ...
Page 264: ...264 Chapter 14 Certificates NN47923 500 Figure 83 My Certificates ...
Page 270: ...270 Chapter 14 Certificates NN47923 500 Figure 85 My Certificate create ...
Page 274: ...274 Chapter 14 Certificates NN47923 500 Figure 86 My Certificate details ...
Page 282: ...282 Chapter 14 Certificates NN47923 500 Figure 89 Trusted CA details ...
Page 298: ...298 Chapter 14 Certificates NN47923 500 ...
Page 316: ...316 Chapter 16 IEEE 802 1x NN47923 500 ...
Page 320: ...320 Chapter 17 Authentication server NN47923 500 Figure 106 Local User database edit ...
Page 328: ...328 Chapter 17 Authentication server NN47923 500 ...
Page 376: ...376 Chapter 20 Logs Screens NN47923 500 Figure 150 Log settings ...
Page 386: ...386 Chapter 20 Logs Screens NN47923 500 ...
Page 393: ...Chapter 21 Call scheduling screens 393 Nortel Business Secure Router 252 Configuration Basics ...
Page 394: ...394 Chapter 21 Call scheduling screens NN47923 500 ...
Page 410: ...410 Chapter 22 Maintenance NN47923 500 ...