Connection Direction, LAN to WAN Rules | ZyXEL Communications P-312

P312 Broadband Security Gateway

16.3 Connection Direction

This section talks about configuring firewall rules for connections going from LAN to WAN and WAN to LAN in your firewall.

16.3.1 LAN to WAN Rules

The default rule for LAN to WAN traffic is that all users on the LAN are allowed non-restricted access to the WAN. When you configure Policy -> LAN to WAN -> Rules, you in essence want to limit some or all users from accessing certain services on the WAN. See the following figure.

Figure 16-1 LAN to WAN Traffic

16.3.2 WAN to LAN Rules

By default NO incoming connections (WAN to LAN) are allowed unless you create rules allowing certain WAN users access to your LAN. See the following figure.

Creating Custom Rules

16-3

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ZyXEL Communications P-312 manual Connection Direction, LAN to WAN Rules, WAN to LAN Rules

Contents

Prestige Copyright DisclaimerTrademarks Federal Communications Commission FCC Interference Statement Information for Canadian Users Version Declaration of Conformity P312 Broadband Security Gateway CE Doc ZyXEL Limited Warranty Information in Menu 24.2.1 -System Information Customer Support Table of Contents LAN Port Filter Setup Chapter Advanced Management 12-1 13-1 Firewall and Content Filters 17-1 Pptp 21-1 Menu 11.1 Remote Node Profile for Ethernet Encapsulation List of Figures List Of Figures Xvii Xviii List Of Figures Xix Menu 21 Filter and Firewall Setup 14-1 List Of Figures Xxi Page List Of Tables Xxiv List of Tables Xxv Page Preface About Your RouterStructure of this Manual Syntax Conventions Related Documentation Part Page Features of The Prestige Getting to Know Your PrestigePrestige 312 Broadband Security Gateway IP Multicast Dhcp Dynamic Host Configuration ProtocolTime and Date Setting Dynamic DNS Support Logging and Tracing Broadband Internet Access via Cable or xDSL ModemUpgrade Prestige Firmware via LAN Applications for Prestige Secure Internet Access via DSL LED functions Hardware Installation & Initial SetupFront Panel LEDs and Back Panel Ports Front Panel LEDs WAN Prestige 312 Rear Panel and Connections Additional Installation Requirements Initial Screen HousingPower Up Your Prestige Entering Password Enter Main Menu CommandsNavigating the SMT Interface Operation Keystrokes Description Main Menu Summary Main MenuSystem Management Terminal Interface Summary Prestige 312 Main Menu Resetting the Prestige Changing the System Password General Setup Dynamic DNSDyndns Wildcard Field Description Example Configuring Dynamic DNSGeneral Setup Menu Field Configure Menu 1.1 Configure Dynamic DNS discussed next Me.ddns.org WAN SetupConfigure Dynamic DNS Menu Fields Yes WAN Setup Menu Fields LAN Setup 10 Menu 3 LAN Setup LAN Port Filter Setup IP Address and Subnet Mask Internet AccessFactory LAN Defaults TCP/IP and Dhcp for LAN Private IP Addresses RIP Setup DNS Server Address Dhcp ConfigurationIP Pool Setup IP Multicast TCP/IP and Dhcp Ethernet Setup IP AliasPhysical Network Partitioned Logical Networks Menu 3 LAN Setup 10/100 Mbps Ethernet LAN TCP/IP Setup Menu Fields LAN Dhcp Setup Menu Fields IP Alias Setup Menu 3.2.1 IP Alias SetupIP Alias Setup Menu Fields RIP-1 Internet Access SetupEthernet Encapsulation Only/Out Only Pptp Encapsulation Internet Access Setup Menu Fields Prestige automatically disconnects from the Pptp server Configuring the Pptp ClientPPPoE Encapsulation New Fields in Menu 4 Pptp screen Internet Access Setup PPPoE New Fields in Menu 4 PPPoE screen Basic Setup Complete Advanced Applications Remote Node Profile Remote Node Setup Fields in Menu Nailed-Up Connection Fields in Menu 11.1 PPPoE Encapsulation Specific Fields in Menu 11.1 Pptp Encapsulation Remote Node Network Layer Options Menu Fields Editing TCP/IP Options with Ethernet Encapsulation 2B/RIP-2M and None Multicast Editing TCP/IP Options with Pptp EncapsulationPrivate Version Remote Node Network Layer Options None/In Only/Out Only and None Remote Node FilterEditing TCP/IP Options with PPPoE Encapsulation Yes/No Remote Node Filter Ethernet Encapsulation Example of Static Routing Topology IP Static Route Setup Menu 12 IP Static Route Setup IP Static Route Setup Field Description IP Static Route Menu FieldsPage What NAT Does Network Address Translation NATIntroduction NAT Definitions NAT Mapping Types How NAT works SUA Single User Account Versus NAT NAT Mapping TypesType IP Mapping SMT abbreviation SMT Menus NAT ApplicationApplying NAT in the SMT Menus Applying NAT for Internet Access Applying NAT in Menus 4 Configuring NATField Options Description Network Full Feature Address Mapping Sets and NAT Server Sets Menu 15.1 Address Mapping Sets Server Field Description Options/Example Menu Ordering Your Rules Editing an Individual Rule in a Set Menu 15.1.1.1 configuring an individual rule Multiple Servers behind NAT NAT Server Sets 10 Multiple Servers Behind NAT Configuring a Server behind NAT Internet Access Only Services Port NumberExamples NAT Example 13 Internet Access & NAT Example Example 3 General Case Example 2 Internet Access with an Inside Server 16 NAT Example 17 Example 3 Menu 19 Example 3 Final Menu 21 NAT Example Example 4 -NAT Unfriendly Application Programs 22 Example 4- Menu 15.1.1.1 Address Mapping Rule Advanced Management Page About Filtering Filter Configuration Filter Structure of the Prestige Rule Forward Drop Filter Rule Process Menu 21 Filter and Firewall Setup Configuring a Filter Set NetBIOSWAN Filter Rules Summary Action Not Matched will be N/A Refers to Action Matched Filter Rules Summary MenuAbbreviations Used in the Filter Rules Summary Menu Abbreviations Description Display Abbreviations Used If Filter Type Is GEN Configuring a Filter Rule3 TCP/IP Filter Rule Abbreviations Used If Filter Type Is IP TCP/IP Filter Rule Menu Fields Menu 21.1.1.1 TCP/IP Filter Rule Action Matched None/Less/GreaterEqual/Not Equal Yes / No Following diagram illustrates the logic flow of an IP filter 10 Executing an IP Filter 11 Menu 21.4.1.1 Generic Filter Rule Generic Filter Rule Generic Filter Rule Menu Fields 12 Telnet Filter Example Example Filter 13 Example Filter Menu 14 Example Filter Rules Summary Menu Filter Types and NAT Applying a Filter and Factory Defaults FirewallLAN traffic 16 Filtering LAN Traffic Remote Node Filters Snmp Configuration Configuring SnmpAbout Snmp Field Description Default Snmp Configuration Menu Fields System Information & Diagnosis Menu 24 System Maintenance System Status Menu 24.1 System Maintenance Status Dhcp System Maintenance Status Menu FieldsPPPoE Encapsulation LAN System Information System Information and Console Port Speed Fields in System Maintenance Log and TraceConsole Port Speed Unix Syslog Viewing Error Log System Maintenance Menu Syslog Parameters Parameter DescriptionCDR CDR PPP log Call-Triggering Packet Diagnostic WAN Dhcp 10 Menu 24.4 System Maintenance Diagnostic System Maintenance Menu Diagnostic Internet Setup in Menu 4 Internet AccessNumber Field Description Filename conventions Transferring Files Filename Conventions Backup ConfigurationCommand Firmware Development Restore Configuration Upload FirmwareUploading the Router Firmware Menu 24.7.1 System Maintenance Upload Router Firmware Uploading Router Configuration File Tftp File Transfer Third Party Tftp Clients -General fields Example Tftp Command Telnet into Menu FTP File Transfer Telnet into Menu 24.7.2 System Maintenance Using the FTP command from the DOS Prompt Third Party FTP Clients -General fields Page System Maintenance & Information Command Interpreter ModeValid Commands Call Control Support Budget ManagementCall Control Call History Call History Time and Date Setting How often does the Prestige update the time?Call History Fields System Maintenance & Information 11-5 Menu 24.11 Remote Management Control Remote Management Setup Option to Enter Debug Mode Boot Commands Boot Module Commands Telnet Under NAT Telnet Configuration and CapabilitiesAbout Telnet Configuration Single Administrator Telnet Under the Firewall System Timeout Firewall and Content Filters Application-level Firewalls What is a FirewallTypes of Firewalls Packet Filtering Firewalls Stateful Inspection firewalls Introduction to ZyXEL’s Firewall Basics Denial of Service Common IP Ports Types of DoS attacks SYN Flood Smurf Attack Stateful Inspection Stateful Inspection Stateful Inspection Process TCP Security Stateful Inspection & the Prestige Guidelines For Enhancing Security With Your Firewall 13.4.4 UDP/ICMP SecurityUpper Layer Protocols Security In General What Is a Firewall? 13-11 Page SMT Main Menu Introducing the Prestige Firewall IP Spoofing View Firewall LogAttack Types Land Legal Smtp Commands Icmp Commands That Trigger AlertsIllegal Commands NetBIOS and Smtp Legal NetBIOS Commands Teardrop Traceroute Big Picture Filtering, Firewall and NAT Packet Filtering Packet Filtering Vs Firewall When To Use Filtering When To Use The FirewallFirewall Page Web Configurator Login and Welcome Screens Introducing the Prestige Web Configurator Enabling the Firewall Prestige Web Configurator Welcome Screen What are Alerts? Mail Mail Screen What are Logs? Mail Smtp Error Messages Smtp Error MessagesExample E-Mail Log Mail Log Attack Alert Threshold Values Half-Open SessionsTCP Maximum Incomplete And Blocking Time Attack Alert Existing half-open sessions Field Description Default Values Do not set Maximum Incomplete High to When TCP Maximum Incomplete isPage Rule Logic Overview Rule ChecklistCreating Custom Rules Rules Overview Security Ramifications Key Fields For Configuring Rules Connection Direction LAN to WAN RulesWAN to LAN Rules WAN to LAN Traffic Services Supported Service Description Services Supported Firewall Rules Summary First Screen Rule Summary Match Block Field Description Option Creating/Editing Firewall Rules Creating/Editing a Firewall Rule Source & Destination Addresses Subnet Address Adding/Editing Source & Destination AddressesSingle Address Range Address Factors Influencing Choices for Timeout Values Timeout Timeout Screen Timeout Menu Field Description Default ValueHour Custom Ports Custom Ports Creating/Editing a Custom Port Creating/Editing a Custom Port Range Single Logs Log ScreenLog Screen Src IP, dest port, src port and protocol Vulnerability, NetBIOS, smtp illegalCommand, traceroute, teardrop, or syn Jan 1 Logs 18-3 Page Example Firewall Rules Activate The Firewall Example 1 E-Mail Screen Example 1 Configuring a Rule Example Firewall Rules 19-5 Example 1 Rule Summary Screen Example 2 Small Office With Mail, FTP and Web Servers Send Alerts When Attacked Configuring a POP Custom Port Example 2 Local Network Rule 1 Configuration Example 2 Local Network Rule Summary 10 Example 2 Internet to Local Network Rule Summary 11 Custom Port for Syslog 12 Syslog Rule Configuration 13 Example 3 Rule Summary Java Content FilteringRestrict Web Features ActiveX Web Proxy Content Filtering Using the Web ConfiguratorBlocking URLs Cookies Content Filtering Fields Field Description Restrict Web FeaturesBlock Web URLs Troubleshooting, Appendices, Glossary and Index Page Problem Corrective Action TroubleshootingProblems Starting Up the Prestige Troubleshooting the Start-Up of your Prestige Troubleshooting the WAN interface Problems with the LAN InterfaceProblems with the WAN interface Troubleshooting the LAN Interface Problems with Internet Access Problems with the FirewallTroubleshooting Internet Access Page Benefits of PPPoE Diagram 1 Single-PC per Modem Hardware ConfigurationAppendix a PPPoE PPPoE in Action Diagram 2 Prestige as a PPPoE Client How PPPoE WorksPrestige as a PPPoE Client Pptp Protocol Overview What is PPTP?Appendix B Pptp and the Prestige Control & PPP connections Appendix C Hardware Specifications MtbfIRD + OTD + Appendix D Important Safety Instructions Function CLI Syntax Appendix E Firewall CLI Commands Sets Function CLI Syntax Description P312 Broadband Security Gateway Delete AC Power Adapter Specifications Appendix F Power Adapter Specs P312 Broadband Security Gateway Glossary of Terms ARPCDR Chap CSU/DSU DCE EMI Dram DSLDslam DTE Hdlc FAQFCC FTP Ipcp PPP IPX IRC ISPMAC PAP NATNdis NIC POP Pots PPPPstn SAP PVCRFC RIP Tftp SpamSTP SUA TCP VPN Page Ddns Index Encapsulation 2-11, 2-12, 3-4 13-6 15-1 ZyNOS