ZyXEL Communications Broadband Security Gateway P-312, Руководство пользователя, Страница: 14 / 254

P312 Broadband Security Gateway
xiv Table Of Contents
15.3 E-Mail .......................................................................................................................................15-3
15.3.1 What are Alerts?................................................................................................................15-3
15.3.2 What are Logs? .................................................................................................................15-4
15.3.3 SMTP Error Messages ......................................................................................................15-6
15.3.4 Example E-Mail Log.........................................................................................................15-6
15.4 Attack Alert...............................................................................................................................15-7
15.4.1 Threshold Values: .............................................................................................................15-8
15.4.2 Half-Open Sessions ...........................................................................................................15-8
Chapter 16
Creating Custom Rules.............................................................................................16-1
16.1 Rules Overview.........................................................................................................................16-1
16.2 Rule Logic Overview ................................................................................................................16-1
16.2.1 Rule Checklist ...................................................................................................................16-1
16.2.2 Security Ramifications ......................................................................................................16-2
16.2.3 Key Fields For Configuring Rules ....................................................................................16-2
16.3 Connection Direction ................................................................................................................16-3
16.3.1 LAN to WAN Rules..........................................................................................................16-3
16.3.2 WAN to LAN Rules..........................................................................................................16-3
16.4 Services Supported....................................................................................................................16-4
16.5 Rule Summary...........................................................................................................................16-6
16.5.1 Creating/Editing Firewall Rules........................................................................................16-8
16.5.2 Source & Destination Addresses.....................................................................................16-10
16.6 Timeout ...................................................................................................................................16-12
16.6.1 Factors Influencing Choices for Timeout Values:...........................................................16-12
Chapter 17 Custom Ports ............................................................................................................17-1
17.1 Introduction...............................................................................................................................17-1
17.2 Creating/Editing A Custom Port ...............................................................................................17-2
Chapter 18
Logs ..........................................................................................................................18-1
18.1 Log Screen ................................................................................................................................18-1
Chapter 19 Example Firewall Rules ............................................................................................19-1
19.1 Examples...................................................................................................................................19-1
19.1.1 Example 1 - Firewall Rule To Allow Web Service From The Internet.............................19-1
19.1.2 Example 2 – Small Office With Mail, FTP and Web Servers...........................................19-6
19.1.3 Example 3: DHCP Negotiation and Syslog Connection from the Internet .....................19-11
Chapter 20
Content Filtering........................................................................................................20-1