User`s manual

P-660 Series Support Notes
142
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Choose Settings button in Remote endpoint section. Please uncheck the boxes of
"Acquire virtual IP address" and "Extended authentication".
Tune IKE proposal to Encryption algorithm as DES, Integrity function as MD5, IKE
mode as main mode, IKE group as MODP 768 (group 1), and IPSec proposal to
Encryption algorithm as DES, Integrity funciton as HMAC-MD5, PFS group as none.