SonicWALL TZ 190 Manuale Utente

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SonicOS Enhanced 4.0 Administrator Guide
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UDP
Detection Prevention
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Enable Stealth Mode - By default, the security appliance responds to incoming connection 
requests as either “blocked” or “open.” If you enable Stealth Mode, your security appliance 
does not respond to blocked inbound connection requests. Stealth Mode makes your 
security appliance essentially invisible to hackers.
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Randomize IP ID - Select Randomize IP ID to prevent hackers using various detection 
tools from detecting the presence of a security appliance. IP packets are given random IP 
IDs, which makes it more difficult for hackers to “fingerprint” the security appliance. 
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Decrement IP TTL for forwarded traffic - Time-to-live (TTL) is a value in an IP packet that 
tells a network router whether or not the packet has been in the network too long and should 
be discarded. Select this option to decrease the TTL value for packets that have been 
forwarded and therefore have already been in the network for some time. 
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Never generate ICMP Time-Exceeded packets - The SonicWALL appliance generates 
Time-Exceeded packets to report when it has dropped a packet because its TTL value has 
decreased to zero. Select this option if you don’t want the SonicWALL appliance to 
generate these reporting packets. 
Dynamic Ports
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Enable support for Oracle (SQLNet) - Select if you have Oracle applications on your 
network.
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Enable support for Windows Messenger - Select this option to support special SIP 
messaging used in Windows Messenger on the Windows XP.
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Enable RTSP Transformations - Select this option to support on-demand delivery of real-
time data, such as audio and video. RTSP (Real Time Streaming Protocol) is an 
application-level protocol for control over delivery of data with real-time properties.
Source Routed Packets
Drop Source Routed Packets is selected by default. Clear the check box if you are testing 
traffic between two specific hosts and you are using source routing.
Connections
Check Disable Anti-Spyware, Gateway AV and IPS Engine (increases maximum SPI 
connections)
 if you want to enable more connections at the expense of the Gateway Anti-Virus 
and Intrusion Prevention services.