Manual


It is a fast and convenient connecting mode to make sure its privacy and authentication without
encryption. NULL Algorithm doesn’t provide any other safety services but a way to substitute ESP
Encryption.
SHA-1 (Secure Hash Algorithm-1):
 A message-digest hash algorithm that takes a message less than 264 bits and produces a 160-bit
digest.
MD5:
 MD5 is a common message digests algorithm that produces a 128-bit message digest from an
arbitrary length input, developed by Ron Rivest.
GRE/IPSec:
 The device Select GRE/IPSec (Generic Routing Encapsulation) packet seal technology.
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