Firewall; Chapter 12 Firewall; Overview; What You Can Do In This Chapter - ZyXEL Communications LTE5121 User Manual

12.1 Overview

Use the LTE Device firewall screens to enable and configure the firewall that protects your LTE
Device and network from attacks by hackers on the Internet and control access to it. By default the

firewall:

• Allows traffic that originates from your LAN computers to go to all other networks.
• Blocks traffic that originates on other networks from going to the LAN.
The following figure illustrates the default firewall action. User A can initiate an IM (Instant
Messaging) session from the LAN to the WAN (1). Return traffic for this session is also allowed (2).
However other traffic initiated from the WAN is blocked (3 and 4).
Figure 84 Default Firewall Action
LAN
A

12.1.1 What You Can Do in this Chapter

• Use the General screen to enable or disable the LTE Device's firewall and set the security level
(Section 12.2 on page
• Use the Services screen to view the configured firewall rules and add, edit or remove a firewall
rule (Section 12.3 on page
• Use the Access Control screen to view and configure incoming/outgoing filtering rules
12.4 on page
• Use the DoS screen to enable or disable Denial of Service (DoS) protection
page 131).
LTE-5121 User's Guide
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