Cisco ASR 5000 Series, Обзор продукта

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Network Address Translation Overview
▀ NAT Feature Overview
▄ Cisco ASR 5000 Series Product Overview
OL-22938-02
bearer ggsn-address: The PGW/GGSN address.
Important:
The NBR attributes: sn-correlation-id, sn-fa-correlation-id, radius-fa-nas-ip-address, radius-fa-nas-
identifier are not applicable for PGW and GGSN.
NAT Binding Updates
Whenever a NAT IP address or NAT port-chunk is allocated/deallocated to/from a subscriber, to update NAT binding
information for that subscriber in the AAA, a NAT Binding Update (NBU) can be sent to the AAA server.
Important:
In the case of P-GW, NBUs is not applicable since it does not use RADIUS.
Since port-chunk allocation/deallocation happens on a per-call basis, this ensures that AAA messaging is reduced to a
great extent. NBUs are sent to the AAA server in accounting-interim messages. To send or not to send NBUs to the
AAA server is configurable in the NAT IP pool configuration.
NBUs are supported for both one-to-one and many-to-one NAT IP pools.
An NBU contains the following attributes:
Alloc-Flag
Binding-Timer
Correlation-Id
Loading-Factor
NAT-IP-Address
NAT-Port-Block-End: In the case of one-to-one NAT, the value is 65535
NAT-Port-Block-Start: In the case of one-to-one NAT, the value is 1
CoA NAT Query
If the NAT binding information is not available at the AAA, the AAA server can query the chassis for the information.
This query uses the Change of Authorization (CoA) format, wherein the AAA sends a one-to-one NAT IP address as a
query, and in the CoA query response the NBU is obtained if available at the time of query.
Important:
In this release, CoA query for NAT binding information is only supported for one-to-one NAT.
The CoA query request must contain the following attributes:
Event-Timestamp
NAS-IP-Address