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Appendix B. Diffie-Hellman Groups

Appendix B. Diffie-Hellman Groups​

There are two Diffie-Hellman groups defined here for use in IKE. These groups were generated by Richard Schroeppel at the University of Arizona. Properties of these primes are described in [OAKLEY].

The strength supplied by group 1 may not be sufficient for typical uses and is here for historic reasons.

Additional Diffie-Hellman groups have been defined in [ADDGROUP].

B.1. Group 1 - 768-bit MODP​

This group is assigned ID 1 (one).

The prime is: 2^768 - 2^704 - 1 + 2^64 * { [2^638 pi] + 149686 }

Its hexadecimal value is:

FFFFFFFF FFFFFFFF C90FDAA2 2168C234 C4C6628B 80DC1CD1
29024E08 8A67CC74 020BBEA6 3B139B22 514A0879 8E3404DD
EF9519B3 CD3A431B 302B0A6D F25F1437 4FE1356D 6D51C245
E485B576 625E7EC6 F44C42E9 A63A3620 FFFFFFFF FFFFFFFF

The generator is 2.

B.2. Group 2 - 1024-bit MODP​

This group is assigned ID 2 (two).

The prime is 2^1024 - 2^960 - 1 + 2^64 * { [2^894 pi] + 129093 }.

Its hexadecimal value is:

FFFFFFFF FFFFFFFF C90FDAA2 2168C234 C4C6628B 80DC1CD1
29024E08 8A67CC74 020BBEA6 3B139B22 514A0879 8E3404DD
EF9519B3 CD3A431B 302B0A6D F25F1437 4FE1356D 6D51C245
E485B576 625E7EC6 F44C42E9 A637ED6B 0BFF5CB6 F406B7ED
EE386BFB 5A899FA5 AE9F2411 7C4B1FE6 49286651 ECE65381
FFFFFFFF FFFFFFFF

The generator is 2.

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