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Comodo Internet Security

Comodo Internet Security

Version 12.2

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Appendix 1 CIS How To... Tutorials > Set Up The Firewall For Maximum Security And Usability
  • Introduction To Comodo Internet Security
    • Special Features
    • Download, Installation And Activation
    • Start Comodo Internet Security
    • The Main Interface
      • The Home Screen
      • The Tasks Interface
      • The Widget
      • The System Tray Icon
    • Understand Security Alerts
  • General Tasks – Introduction
    • Scan And Clean Your Computer
      • Run A Quick Scan
      • Run A Full Computer Scan
      • Run A Rating Scan
      • Run A Custom Scan
        • Scan A Folder
        • Scan A File
        • Create, Schedule And Run A Custom Scan
    • Secure Shopping Settings
    • Manage Virus Database And Program Updates
    • Get Live Support
    • Manage Blocked Items
    • Instantly Scan Files And Folders
    • Process Infected Files
  • Firewall Tasks - Introduction
    • Configure Internet Access Rights For Applications
    • Manage Network Connections
    • Stop All Network Activities
    • Stealth Your Computer Ports
    • View Active Internet Connections
  • Containment Tasks - Introduction
    • Run An Application In The Container
    • Reset The Container
    • Identify And Kill Unsafe Running Processes
    • View Active Process List
    • The Virtual Desktop
      • Start The Virtual Desktop
      • The Main Interface
      • Run Browsers Inside The Virtual Desktop
      • Open Files And Run Applications Inside The Virtual Desktop
      • Configure The Virtual Desktop
      • Close The Virtual Desktop
  • Advanced Tasks – Introduction
    • Create A Rescue Disk
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    • Remove Deeply Hidden Malware
    • Manage CIS Tasks
    • Manage Quarantined Items
    • View CIS Logs
      • Antivirus Logs
      • VirusScope Logs
      • Firewall Logs
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      • Containment Logs
      • Website Filtering Logs
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      • Autorun Event Logs
      • Alerts Logs
      • CIS Tasks Logs
      • File List Changes Logs
      • Vendor List Changes Logs
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      • Search And Filter Logs
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  • CIS Settings
    • General Settings
      • Customize User Interface
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      • Log Settings
      • Manage CIS Configurations
        • Comodo Preset Configurations
        • Personal Configurations
    • Antivirus Configurations
      • Real-time Scan Settings
      • Scan Profiles
    • Firewall Configuration
      • General Firewall Settings
      • Application Rules
      • Global Rules
      • Firewall Rule Sets
      • Network Zones
        • Network Zones
        • Blocked Zones
      • Port Sets
    • HIPS Configuration
      • HIPS Settings
      • Active HIPS Rules
      • HIPS Rule Sets
      • Protected Objects
        • Protected Files
        • Blocked Files
        • Protected Registry Keys
        • Protected COM Interfaces
        • Protected Data Files And Folders
      • HIPS Groups
        • Registry Groups
        • COM Groups
    • Containment Configuration
      • Containment Settings
      • Auto-Containment Rules
      • Containment - An Overview
      • Unknown Files - The Scanning Processes
    • File Rating Configuration
      • File Rating Settings
      • File Groups
      • Submitted Files
    • Advanced Protection Configuration
      • VirusScope Settings
      • Scan Exclusions
      • Device Control Settings
      • Script Analysis Settings
      • Miscellaneous Settings
      • Comodo Secure Shopping
    • Website Filtering Configuration
      • Website Filtering Rules
      • Website Categories
  • Comodo GeekBuddy
    • Download And Install GeekBuddy
    • Overview Of Services
    • Activation Of Service
    • Launch The Client And Use The Service
    • Accept Remote Desktop Requests
    • Uninstall Comodo GeekBuddy
  • TrustConnect Overview
  • Dragon Browser
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  • Comodo Internet Security Essentials
    • What Is Comodo Internet Security Essentials
    • What Is A Man-in-the-middle Attack
    • How Does Comodo Internet Security Essentials Protect Me From A Man-in-the-middle Attack
    • What Is The Install Location Of Comodo Internet Security Essentials
    • How Do I Update CISE
    • Understand Alerts And Configure Exceptions
    • How Do I View CISE Help
    • How Do I View The Version Number And Release Notes
    • How Do I Remove Comodo Internet Security Essentials
  • Appendix 1 CIS How To... Tutorials
    • Enable / Disable AV, Firewall, Auto-Containment, VirusScope And Website Filter Easily
    • Set Up The Firewall For Maximum Security And Usability
    • Block Internet Access While Allowing Local Area Network (LAN) Access
    • Block/Allow Specific Websites To Specific Users
    • Set Up HIPS For Maximum Security And Usability
    • Create Rules To Auto-Contain Applications
    • Password Protect Your CIS Settings
    • Reset Forgotten Password (Advanced)
    • Run An Instant Antivirus Scan On Selected Items
    • Create An Antivirus Scan Schedule
    • Run Untrusted Programs In The Container
    • Run Browsers In The Container
    • Run Untrusted Programs In The Virtual Desktop
    • Run Browsers In The Virtual Desktop
    • Restore Incorrectly Blocked Items
    • Restore Incorrectly Quarantined Items
    • Submit Quarantined Items To Comodo For Analysis
    • Enable File Sharing Applications Like BitTorrent And Emule
    • Block Any Downloads Of A Specific File Type
    • Switch Between Complete CIS Suite And Individual Components (just AV Or FW)
    • Switch Off Automatic Antivirus And Software Updates
    • Suppress CIS Alerts Temporarily While Playing Games
    • Renew Or Upgrade Your License
    • Use CIS Protocol Handlers
    • Configure Secure Shopping
    • Comodo Cloud Backup
    • Give Contained Applications Write Access To Local Folders
    • Use The Comodo Uninstaller Tool
  • Appendix 2 - Comodo Secure DNS Service
    • Router - Enable Comodo Secure DNS Service
    • Windows - Enable Comodo Secure DNS
  • Appendix 3 - Glossary Of Terms
  • Appendix 4 - CIS Versions
  • About Comodo Security Solutions

Set up the Firewall For Maximum Security and Usability

 

This page outlines the functions of Comodo's Firewall and helps you to set up a secure connection to the internet.


Stealth Ports Settings


Port stealthing is a security feature whereby ports on an internet connected PC are hidden from sight, sending no response to opportunistic port scans.


1. Click 'Tasks' > 'Firewall Tasks'


2. Click 'Stealth Ports'




3. Select 'Block Incoming Connections' to make computer's ports are invisible to all networks

Click here for more information about port stealthing

 

Network Zones Settings

 

'Network Zones' settings allow you to configure the protection level for connections to a router/home network (this is usually done automatically for you).

 

View the configurations

  1. Click 'Settings' on the CIS home screen

  2. Click 'Firewall' > 'Network Zones'

  3. Click the 'Network Zones' tab





4. Inspect the 'Loopback zone' and 'Local Area Network #1' (exact name may vary) by clicking the '+' button beside the zone name
  • In most cases, the loopback zone IP address should be 127.0.01/255.0.0.0
  • In most cases, the IP address of the auto -detected Network zone should be 10.nnn.nnn.nnn/255.255.255.0

5. Click 'OK'.

     

Click here for more details on Network Zones settings

 

Firewall Settings


The firewall settings option lets you configure the protection level for your internet connection, and the frequency of alerts generated.

  1. Click 'Settings' at the top of the CIS home screen

  2. Click 'Firewall' > 'Firewall Settings'

  3. Select 'Enable Firewall' and choose 'Safe Mode' from the drop-down




Safe Mode: While filtering network traffic, the firewall will automatically create rules which allow traffic for application components certified as 'Safe' by Comodo. For non-certified, new, applications, you will receive an alert whenever that application attempts to access the network. Should you choose, you can grant that application internet access by choosing 'Treat this application as a Trusted Application' at the alert. This will deploy the predefined firewall policy 'Trusted Application' onto the application.

 

Alert Settings

 

Under 'Alert Settings' in the same interface:

  • Deselect 'Do not show popup alerts'

  • Select 'Set alert frequency level' option and choose 'Low' from the drop-down. At the 'Low' setting, the firewall shows alerts for outgoing and incoming connection requests for an application. This is the setting recommended by Comodo and is suitable for the majority of users.




Advanced Settings

 

When launching a denial of service or 'flood' attack, an attacker bombards a target machine with so many connection requests that your computer is unable to accept legitimate connections, effectively shutting down your web, email, FTP or VPN server. To protect from such attacks, make the following settings under 'Advanced' in the 'Firewall Settings' interface:

  • Select 'Filter loopback traffic'
  • Ensure that the 'Block fragmented IP traffic' is selected
  • Block fragmented IP traffic - When a connection is opened between two computers, they must agree on a Maximum Transmission Unit (MTU). IP Datagram fragmentation occurs when data passes through a router with an MTU less than the MTU you are using i.e when a datagram is larger than the MTU of the network over which it must be sent, it is divided into smaller 'fragments' which are each sent separately. Fragmented IP packets can create threats similar to a DOS attack. Moreover, these fragmentations can double the amount of time it takes to send a single packet and slow down your download time.
  • Select the 'Do Protocol Analysis' checkbox to detect fake packets used in denial of service attacks
  • Select 'Enable anti-ARP spoofing'



     
4. Click 'OK' for your settings to take effect.
Click here for more details on Firewall Settings


Set-up Application Rules, Global Rules and Predefined Firewall Rulesets


You can configure and deploy traffic filtering rules and policies on an application-specific and global basis.

 

View the Application Rules


1. Click 'Settings on the CIS home screen

2. Click 'Firewall' > 'Application Rules'



3. Click 'Add' to create a new application rule

4. Select a rule and click 'Edit' to edit the rules for a specific application manually or click 'Remove' to remove them.

5. Click 'OK' for your settings to take effect.

Click here for more details on Application Rules

 

View the Global Rules


1. Click 'Settings' on the CIS home screen

2. Click 'Firewall' > 'Global Rules'.




3. Click 'Add' to create a new global rule.

4. Select a rule and click 'Edit' to edit the a rule manually or click 'Remove' to remove them.

5. Click 'OK' for your settings to take effect.

Click here for more details on Global Rules

 

View Predefined Firewall rulesets


1. Click 'Settings' on the CIS home screen

2. Click 'Firewall' > 'Rulesets'



 

3. Click 'Add' to add a new ruleset.


4. Select a ruleset and click 'Edit' to edit the rules manually or click 'Remove' to remove them.

5. Click 'OK' for your settings to take effect.


You need not make your own rulesets, the defaults are usually enough.


Click here for more details on pre-defined firewall rulesets

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