Cisco Cisco Packet Data Gateway (PDG) Fehlerbehebungsanleitung
IP Security
Overview ▀
Cisco ASR 5000 Series Enhanced Feature Configuration Guide ▄
OL-22983-01
Overview
IP Security (IPSec) is a suite of protocols that interact with one another to provide secure private communications across
IP networks. These protocols allow the system to establish and maintain secure tunnels with peer security gateways.
IPSec can be implemented on the system for the following applications:
IP networks. These protocols allow the system to establish and maintain secure tunnels with peer security gateways.
IPSec can be implemented on the system for the following applications:
PDN Access: Subscriber IP traffic is routed over an IPSec tunnel from the system to a secure gateway on the packet data
network (PDN) as determined by access control list (ACL) criteria. This application can be implemented for both core
network service and HA-based systems. The following figure shows IPSec configurations.
network (PDN) as determined by access control list (ACL) criteria. This application can be implemented for both core
network service and HA-based systems. The following figure shows IPSec configurations.
Figure 20. IPSec Applications
IPSec Tunnel
L2TP
Application
Core service
or HA
Security
Gateway
Packet Data Network
HA
IPSec Tunnel
IPSec Tunnel
LNS/Security
Gateway
Core
service/FA
Core service/LAC
HA/LAC
Mobile IP
Application
PDN Access
Application
Mobile IP: Mobile IP control signals and subscriber data is encapsulated in IPSec tunnels that are established between
foreign agents (FAs) and home agents (HAs) over the Pi interfaces.
foreign agents (FAs) and home agents (HAs) over the Pi interfaces.
Important:
Once an IPSec tunnel is established between an FA and HA for a particular subscriber, all
new Mobile IP sessions using the same FA and HA are passed over the tunnel regardless of whether or not
IPSec is supported for the new subscriber sessions. Data for existing Mobile IP sessions is unaffected.
IPSec is supported for the new subscriber sessions. Data for existing Mobile IP sessions is unaffected.
L2TP: L2TP-encapsulated packets are routed from the system to an LNS/secure gateway over an IPSec tunnel.