VPN
Setting Up a Gateway to Gateway (Site to Site) VPN
Cisco Small Business RV0xx Series Routers Administration Guide
134
9
Preshared Key, page 135
and
Advanced settings for IKE with
Preshared Key, page 136
.
•
Required fields for Manual mode
Enter the settings for manual mode. Be sure to enter the same settings when
configuring other router for this tunnel. The Incoming / Outgoing SPI settings
must be mirrored on the other router.
-
Incoming
/
Outgoing SPI:
The Security Parameter Index is carried in the
ESP (Encapsulating Security Payload Protocol) header and enables the
receiver and sender to select the security association, under which a
packet should be processed. You can enter hexadecimal values from
100~ffffffff. Each tunnel must have a unique Incoming SPI and Outgoing
SPI. No two tunnels share the same SPI. The Incoming SPI here must
match the Outgoing SPI value at the other end of the tunnel, and vice
versa.
-
Encryption:
Select a method of encryption: DES or 3DES. This setting
determines the length of the key used to encrypt or decrypt ESP
packets. DES is 56-bit encryption and 3DES is 168-bit encryption. 3DES
is recommended because it is more secure.
-
Authentication:
Select a method of authentication: MD5 or SHA1. The
authentication method determines how the ESP packets are validated.
MD5 is a one-way hashing algorithm that produces a 128-bit digest.
SHA1 is a one-way hashing algorithm that produces a 160-bit digest.
SHA1 is recommended because it is more secure. Make sure that both
ends of the VPN tunnel use the same authentication method.
-
Encryption Key:
Enter a key to use to encrypt and decrypt IP traffic. If
you selected DES encryption, enter 16 hexadecimal values. If you
selected 3DES encryption enter 40 hexadecimal values. If you do not
enter enough hexadecimal values, then zeroes will be appended to the
key to meet the required length.
-
Authentication Key:
Enter a key to use to authenticate IP traffic. If you
selected MD5 authentication, enter 32 hexadecimal values. If you
selected SHA1, enter 40 hexadecimal values. If you do not enter enough
hexadecimal values, then zeroes will be appended to the key to meet
the required length.