Cisco ASR 5000 Series, Обзор продукта

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CDMA2000 Wireless Data Services
Features and Functionality - Optional Enhanced Software Features ▀
Cisco ASR 5000 Series Product Overview ▄
OL-22938-02
L2TP establishes L2TP control tunnels between LAC and LNS before tunneling the subscriber PPP connections as
L2TP sessions. There can be a maximum of up to 65535 sessions in a single tunnel and up to 500,000 sessions per LNS.
The LNS architecture is similar to the PDSN and utilizes the concept of a de-multiplexer to intelligently assign new
L2TP sessions across the available software and hardware resources on the platform without operator intervention..
Important:
For more information on L2TP LNS support support, refer L2TP Access Concentrator chapter in
System Enhanced Feature Configuration Guide .
Proxy Mobile IP
Mobility for subscriber sessions is provided through the Mobile IP protocol as defined in RFCs 2002-2005. However,
some older Mobile Nodes (MNs) do not support the Mobile IP protocol. The Proxy Mobile IP feature provides a
mobility solution for these MNs.
Description
For IP PDP contexts using Proxy Mobile IP, the MN establishes a session with the PDSN as it normally would.
However, the PDSN/FA performs Mobile IP operations with an HA (identified by information stored in the subscriber's
profile) on behalf of the MN (i.e. the MN is only responsible for maintaining the IP PDP context with the PDSN, no
Agent Advertisement messages are communicated with the MN).
The MN is assigned an IP address by either the HA, an AAA server, or on a static-basis. The address is stored in a
Mobile Binding Record (MBR) stored on the HA. Therefore, as the MN roams through the service provider's network,
each time a hand-off occurs, the MN will continue to use the same IP address stored in the MBR on the HA.
Proxy Mobile IP can be performed on a per-subscriber basis based on information contained in their user profile, or for
all subscribers facilitated by a specific subscriber. In the case of non-transparent IP PDP contexts, attributes returned
from the subscriber's profile take precedence over the configuration of the subscriber.
Important:
For more information on Proxy Mobile IP configuration, refer Proxy Mobile IP chapter in System
Enhanced Feature Configuration Guide.
IP Security (IPSec)
IP Security provides a mechanism for establishing secure tunnels from mobile subscribers to pre-defined endpoints (i.e.
enterprise or home networks) in accordance with the following standards:
RFC 2401, Security Architecture for the Internet Protocol
RFC 2402, IP Authentication Header (AH)
RFC 2406, IP Encapsulating Security Payload (ESP)