D-Link NetDefendOS User Manual page 7

6.2.5. The TFTP ALG ............................................................................ 447
6.2.6. The SMTP ALG ........................................................................... 448
6.2.7. The POP3 ALG ........................................................................... 457
6.2.8. The PPTP ALG ............................................................................ 461
6.2.9. The SIP ALG .............................................................................. 463
6.2.10. The H.323 ALG ......................................................................... 479
6.2.11. The TLS ALG ............................................................................ 500
6.3. Web Content Filtering ........................................................................... 503
6.3.1. Overview .................................................................................. 503
6.3.2. Active Content Handling ............................................................. 503
6.3.3. Static Content Filtering ............................................................... 504
6.3.4. Dynamic Web Content Filtering ................................................... 507
6.4. Email Filtering and Anti-Spam ................................................................ 526
6.4.1. IP Policy Based Email Filtering ...................................................... 526
6.4.2. ALG Based Email Filtering ............................................................ 534
6.4.3. DNSBL Databases ...................................................................... 539
6.5. Anti-Virus Scanning .............................................................................. 541
6.5.1. Overview .................................................................................. 541
6.5.2. Implementation ........................................................................ 542
6.5.3. Anti-Virus Options ..................................................................... 545
6.5.4. Activating Anti-Virus Scanning ..................................................... 546
6.5.5. The Anti-Virus Cache .................................................................. 550
6.6. Intrusion Detection and Prevention ........................................................ 552
6.6.1. Overview .................................................................................. 552
6.6.2. IDP Subscriptions ....................................................................... 553
6.6.3. IDP Rules .................................................................................. 554
6.6.4. Insertion/Evasion Attack Prevention ............................................. 556
6.6.5. IDP Pattern Matching ................................................................. 557
6.6.6. IDP Signature Groups ................................................................. 558
6.6.7. Setting Up IDP ........................................................................... 559
6.6.8. SMTP Log Receiver for IDP Events ................................................. 562
6.6.9. Best Practice Deployment ........................................................... 564
6.7. Denial-of-Service Attacks ....................................................................... 566
6.7.1. Overview .................................................................................. 566
6.7.2. DoS Attack Mechanisms .............................................................. 566
6.7.3. Ping of Death Attacks .................................................................. 566
6.7.4. Fragmentation Overlap Attacks .................................................... 567
6.7.5. The Land and LaTierra Attacks ...................................................... 567
6.7.6. The WinNuke attack .................................................................... 567
6.7.7. Amplification Attacks ................................................................. 568
6.7.8. TCP SYN Flood Attacks ................................................................ 569
6.7.9. The Jolt2 Attack ......................................................................... 569
6.7.10. Distributed DoS Attacks ............................................................ 570
6.8. Blacklisting Hosts and Networks ............................................................. 571
7. Address Translation ........................................................................................ 574
7.1. Overview ............................................................................................ 574
7.2. NAT ................................................................................................... 576
7.3. NAT Pools ........................................................................................... 584
7.4. SAT .................................................................................................... 588
7.4.1. Introduction ............................................................................. 588
7.4.2. One-to-One IP Translation ........................................................... 590
7.4.3. Many-to-Many IP Translation ....................................................... 593
7.4.4. All-to-One IP Translation ............................................................. 596
7.4.5. Port Translation ......................................................................... 599
7.4.6. SAT with FwdFast Rules ............................................................... 600
7.4.7. Using an IP Policy for SAT ............................................................ 601
7.4.8. Protocols Handled by SAT ........................................................... 602
7.4.9. SAT with NAT ............................................................................ 603
8. User Authentication ........................................................................................ 608
8.1. Overview ............................................................................................ 608
8.2. Authentication Setup ............................................................................ 610
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User Manual