Chapter 19 IPSec VPN
ZyWALL USG 50-H User’s Guide
331
The ZyWALL sends one or more proposals to the remote IPSec router. (In some devices, you
can only set up one proposal.) Each proposal consists of an encryption algorithm,
authentication algorithm, and DH key group that the ZyWALL wants to use in the IKE SA.
The remote IPSec router selects an acceptable proposal and sends the accepted proposal back
to the ZyWALL. If the remote IPSec router rejects all of the proposals, the ZyWALL and
remote IPSec router cannot establish an IKE SA.
"
Both routers must use the same encryption algorithm, authentication
algorithm, and DH key group.
In most ZyWALLs, you can select one of the following encryption algorithms for each
proposal. The algorithms are listed in order from weakest to strongest.
• Data Encryption Standard (DES) is a widely used method of data encryption. It applies a
56-bit key to each 64-bit block of data.
• Triple DES (3DES) is a variant of DES. It iterates three times with three separate keys,
effectively tripling the strength of DES.
• Advanced Encryption Standard (AES) is a newer method of data encryption that also uses
a secret key. AES applies a 128-bit key to 128-bit blocks of data. It is faster than 3DES.
Some ZyWALLs also offer stronger forms of AES that apply 192-bit or 256-bit keys to 128-
bit blocks of data.
In most ZyWALLs, you can select one of the following authentication algorithms for each
proposal. The algorithms are listed in order from weakest to strongest.
• MD5 (Message Digest 5) produces a 128-bit digest to authenticate packet data.
• SHA1 (Secure Hash Algorithm) produces a 160-bit digest to authenticate packet data.
See
Diffie-Hellman (DH) Key Exchange on page 331
for more information about DH key
groups.
Diffie-Hellman (DH) Key Exchange
The ZyWALL and the remote IPSec router use DH public-key cryptography to establish a
shared secret. The shared secret is then used to generate encryption keys for the IKE SA and
IPSec SA. In main mode, this is done in steps 3 and 4, as illustrated next.
Figure 248
IKE SA: Main Negotiation Mode, Steps 3 - 4: DH Key Exchange
1
2
X
Y
Diffie-Hellman key exchange
Содержание ZyWall USG 50-H Series
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Страница 10: ...Safety Warnings ZyWALL USG 50 H User s Guide 10...
Страница 28: ...Table of Contents ZyWALL USG 50 H User s Guide 28...
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Страница 34: ...Chapter 1 Introducing the ZyWALL ZyWALL USG 50 H User s Guide 34...
Страница 40: ...Chapter 2 Features and Applications ZyWALL USG 50 H User s Guide 40...
Страница 92: ...Chapter 5 Configuration Basics ZyWALL USG 50 H User s Guide 92...
Страница 130: ...Chapter 6 Tutorials ZyWALL USG 50 H User s Guide 130...
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Страница 156: ...Chapter 8 Interface ZyWALL USG 50 H User s Guide 156 Figure 128 Network Interface Ethernet Edit wan2...
Страница 157: ...Chapter 8 Interface ZyWALL USG 50 H User s Guide 157 Figure 129 Network Interface Ethernet Edit lan1...
Страница 208: ...Chapter 8 Interface ZyWALL USG 50 H User s Guide 208 Figure 161 Network Interface Bridge Add...
Страница 224: ...Chapter 9 Trunks ZyWALL USG 50 H User s Guide 224...
Страница 250: ...Chapter 12 Zones ZyWALL USG 50 H User s Guide 250...
Страница 280: ...Chapter 16 ALG ZyWALL USG 50 H User s Guide 280...
Страница 286: ...Chapter 17 IP MAC Binding ZyWALL USG 50 H User s Guide 286...
Страница 287: ...287 PART III Firewall Firewall 289...
Страница 288: ...288...
Страница 304: ...Chapter 18 Firewall ZyWALL USG 50 H User s Guide 304...
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Страница 313: ...Chapter 19 IPSec VPN ZyWALL USG 50 H User s Guide 313 Figure 238 VPN IPSec VPN VPN Connection Edit IKE...
Страница 356: ...Chapter 21 SSL User Screens ZyWALL USG 50 H User s Guide 356...
Страница 358: ...Chapter 22 SSL User Application Screens ZyWALL USG 50 H User s Guide 358...
Страница 368: ...Chapter 24 L2TP VPN ZyWALL USG 50 H User s Guide 368...
Страница 394: ...Chapter 25 L2TP VPN Example ZyWALL USG 50 H User s Guide 394...
Страница 395: ...395 PART V Application Patrol Application Patrol BWM 397...
Страница 396: ...396...
Страница 421: ...421 PART VI Anti X ADP 423...
Страница 422: ...422...
Страница 429: ...Chapter 27 ADP ZyWALL USG 50 H User s Guide 429 Figure 359 Profiles Traffic Anomaly...
Страница 432: ...Chapter 27 ADP ZyWALL USG 50 H User s Guide 432 Figure 360 Profiles Protocol Anomaly...
Страница 440: ...Chapter 27 ADP ZyWALL USG 50 H User s Guide 440...
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Страница 462: ...Chapter 29 Addresses ZyWALL USG 50 H User s Guide 462...
Страница 474: ...Chapter 31 Schedules ZyWALL USG 50 H User s Guide 474...
Страница 484: ...Chapter 32 AAA Server ZyWALL USG 50 H User s Guide 484...
Страница 506: ...Chapter 34 Certificates ZyWALL USG 50 H User s Guide 506...
Страница 510: ...Chapter 35 SSL Application ZyWALL USG 50 H User s Guide 510...
Страница 511: ...511 PART VIII System System 513...
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Страница 568: ...Chapter 38 Logs ZyWALL USG 50 H User s Guide 568 Figure 464 Maintenance Log Log Setting Edit System Log...
Страница 584: ...Chapter 40 Diagnostics ZyWALL USG 50 H User s Guide 584...
Страница 586: ...Chapter 41 Reboot ZyWALL USG 50 H User s Guide 586...
Страница 596: ...Chapter 43 Product Specifications ZyWALL USG 50 H User s Guide 596...
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Страница 636: ...Appendix A Log Descriptions ZyWALL USG 50 H User s Guide 636...
Страница 640: ...Appendix B Common Services ZyWALL USG 50 H User s Guide 640...
Страница 646: ...Appendix C Importing Certificates ZyWALL USG 50 H User s Guide 646...