Virtual vpn in the cloud

2
RELATED WORK .......................................................................................................... 5
2.1 O
PEN
VPN
A
NALYSIS
...................................................................................................... 5 
2.2 IPS
EC PERFORMANCE ON 
F
EDORA AND 
W
INDOWS 
O
PERATING 
S
YSTEMS
.................... 5 
2.3 IPS
EC COMPLEXITIES
...................................................................................................... 5 
2.4 A
NALYSIS OF 
E
NCRYPTION 
A
LGORITHMS ON SITE
-
TO
-
SITE 
VPN
S
................................ 6 
2.5 P
ERFORMANCE EVALUATION OF SOFTWARE 
VPN
S
........................................................ 6 
2.6 P
ERFORMANCE 
E
VALUATION OF 
R
EMOTE 
A
CCESS 
VPN
S
............................................. 6 
2.7 A
NALYSIS OF 
IPS
EC OVERHEADS FOR 
VPN
SERVERS
.................................................... 6 
3
IPSEC VPN ASSOCIATIONS ........................................................................................ 8
3.1 IPS
EC
............................................................................................................................... 8 
3.1.1 IPSec Features ............................................................................................................. 8 
3.1.2 IPSec Functionality ...................................................................................................... 8 
3.1.3 IPSec Modes of Operation ........................................................................................... 8 
3.1.4 Encapsulation Security Payload and Authentication Header ...................................... 9 
3.1.5 Internet Key Exchange .............................................................................................. 10 
3.2 K
EY 
D
ISTRIBUTION 
M
ECHANISMS
................................................................................ 10 
3.2.1 Pre-Shared Keys ........................................................................................................ 11 
3.2.2 Digital Certificates ..................................................................................................... 11 
3.3 C
OMPARATIVE 
A
NALYSIS OF 
D
IFFERENT 
A
RCHITECTURES
......................................... 12 
3.3.1 Site-to-Site VPNs ...................................................................................................... 13 
3.3.2 Remote Access VPNs ................................................................................................ 14 
3.3.3 Host-to-Host VPNs .................................................................................................... 15