Proroute
GEM
2M
4G
Router
GEM-2M series User Manual
91
Group 2 (MODP1024), Group 5 (MODP1536) and Group14 ~ 18. Once the PFS
Group is selected in one IPSec proposal, the one in other 3 IPSec proposals
uses the same choice.
4.
Enable:
Check this box to enable the IKE Proposal during tunnel establishing.
3.2.3.2.11 Manual Proposal
When “Manually” key management is used, there are 4 further parameters need to be
specified by you and used in IPSec tunnel establishing.
1.
Outbound SPI:
SPI is an important parameter during hashing. Outbound SPI
will be included in the outbound packet transmitted from local gateway. The
value of outbound SPI should be set in hex formatted.
2.
Inbound SPI:
Inbound SPI will be included in the inbound packet transmitted
from remote VPN peer. It will be used to de-hash the coming packet and check
its integrity. The value of inbound SPI should be set in hex formatted.
3.
Encryption Algorithm:
There are five algorithms can be selected: DES, 3DES,
AES-128, AES-192, and AES-256. Encryption key is used by the encryption
algorithm. Its length is 16 in hex format if encryption algorithm is DES or 48 if
3DES. However, AES-128 uses 32 length of hex format, AES-192 uses 48
length of hex format, and AES-256 uses 64 length of hex format. The key value
should be set in hex formatted here.
4.
Authentication:
There are five algorithms can be selected: None, MD5, SHA1,
SHA2-256 and SHA2-512. Authentication key is used by the authentication
algorithm and its length is 32 in hex format if authentication algorithm is MD5 or
40 if SHA1. However, SHA2-256 uses 64 length of hex format. Certainly, its
length will be 0 if no authentication algorithm is chosen. The key value should be
also set in hex formatted.
3.2.3.3 PPTP
The Point-to-Point Tunneling Protocol (PPTP) is a method for implementing virtual
private networks. PPTP uses a control channel over TCP and a GRE tunnel operating
to encapsulate PPP packets. The PPTP specification does not describe encryption or
authentication features and relies on the Point-to-Point Protocol being tunneled to
