Windows 7 / Networking

Windows Firewall and the Startup Process

When a computer running Windows 7 starts, boot-time filters are applied to all network interfaces to reduce the attack surface prior to the Windows Firewall service (MpsSvc) starting. The boot-time filters perform the following actions:

  • Block all unsolicited inbound traffic to the computer.
  • Allow all inbound Dynamic Host Configuration Protocol (DHCP) traffic.
  • Allow inbound Internet Control Message Protocol 6 (ICMPv6) Type 135:* Neighbor Discovery traffic.
  • Allow all outbound traffic.
  • Block outbound TCP Resets.
  • Block outbound ICMPv6 Type 1:3 and ICMPv4 Type 3:3 Destination Unreachable / Port Unreachable error messages.

Once the BFE has initialized, Windows switches to using persistent filters until MpsSvc starts. These persistent filters are identical in policy to the boot-time filters. Once MpsSvc starts, Windows Firewall policy is processed and applied to the computer.

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In this tutorial:

  1. Configuring Windows Firewall and IPsec
  2. Understanding Windows Firewall with Advanced Security
  3. Improvements to Windows Firewall Introduced Previously in Windows Vista
  4. Additional Improvements to Windows Firewall in Windows 7
  5. Understanding the Windows Filtering Platform
  6. Windows Firewall and the Startup Process
  7. Understanding Windows Service Hardening
  8. Understanding Service SIDs
  9. Windows Firewall and WSH
  10. Windows Firewall and Service Triggers
  11. Understanding Multiple Active Firewall Profiles
  12. Understanding Rules
  13. Understanding Firewall Rules
  14. Inbound vs . Outbound Rules
  15. Allow vs . Block Rules
  16. Allow If Secure Rules
  17. Authenticated Bypass Rules
  18. Filtering Conditions FOR Firewall RULES
  19. Understanding Connection Security Rules
  20. Types of Connection Security Rules
  21. Supported IPsec Settings for Connection Security Rules
  22. Default IPsec Settings for Connection Security Rules
  23. Windows Firewall and Windows PE
  24. Understanding Default Rules
  25. Understanding WSH Rules
  26. Understanding Rules Processing
  27. Managing Windows Firewall with Advanced Security
  28. Tools for Managing Windows Firewall with Advanced Security
  29. Managing Windows Firewall Using Control Panel
  30. Managing Windows Firewall Using the Windows Firewall with Advanced Security Snap-in
  31. Managing Windows Firewall Using Group Policy
  32. Considerations When Managing Windows Firewall Using Group Policy
  33. Managing Windows Firewall Using the Netsh Command
  34. Common Management Tasks
  35. Enabling or Disabling Windows Firewall
  36. Configuring Firewall Profiles and IPsec Settings by Using Group Policy
  37. Creating and Configuring Firewall Rules
  38. Creating and Configuring Connection Security Rules
  39. Monitoring Windows Firewall
  40. Troubleshooting Windows Firewall
  41. Troubleshooting Windows Firewall Using Firewall Logs
  42. Troubleshooting Windows Firewall Using Event Logs
  43. Troubleshooting Windows Firewall Using Auditing
  44. Troubleshooting IPsec Issues Using Netsh Wfp
  45. Troubleshooting Windows Filtering Platform and IPsec Issues Using Netsh Trace