Zte ZXR10 ZSR V2 Series - Ipsec + GRE; Figure 3-3 Ipsec+Gre VPN Schematic Diagram

ZXR10 ZSR V2 Series Router Product Description
ZTE Confidential & Proprietary 29
address and supports DHCP and private address application (RFC1918). Address
distributed for remote user is not Internet address but internal private address of
enterprise network, which facilitates address management and enhances security.
 Network accounting flexibility: accounting could be implemented at LAC (usually is
ISP) and LNS (usually is enterprise) at the same time. The former accounting
generates bills and the latter is for payment and auditing. L2TP can provide
accounting data of data transmission such as incoming and outgoing packets
number, bytes number, beginning and ending time for connection.
 Reliability: L2TP protocol supports LNS backup. When main LNS is unreachable,
LAC (access server) can re-establish connection with backup LNS to improve VPN
service reliability and error tolerance.
 Integrated network management: L2TP protocol has become standard RFC protocol.
Related L2TP standard MIB has been established. In this way SNMP network
management solution can be integrated adopted to implement easy network
maintenance and management.
3.5.5 IPSec + GRE
The IPSec tunnel only supports unicast flow, multicast data can not be protected.GRE can
can encapsulate non-IP packets, IP multicast and broadcast packets, so you can use
GRE over IPSec to protect the data in GRE tunnel, thereby protecting the GRE tunnel
multicast data flow.
Figure 3-3 IPSec+GRE VPN schematic diagram