Cisco ASR 5000 Series, Обзор продукта

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Packet Data Interworking Function Overview
▀ Features and Functionality - Licensed Enhanced Feature Support
▄ Cisco ASR 5000 Series Product Overview
OL-22938-02
second is known as the TSr (Traffic Selector-responder). Each traffic selector payload contains one or more traffic
selectors, and each traffic selector can contain an IP address range, a port range, and an IP protocol ID. During traffic
selector negotiation between the UE and the PDIF, the UE assumes the role of the initiator as it initiates an IPSec SA for
its traffic, and the PDIF assumes the role of the responder. The PDIF can use multiple traffic selectors in its role as the
responder.
Traffic selectors are applied to calls via an AAA attribute. During call setup, the PDIF's AAA manager selects the traffic
class to use for a call based on the Radius vendor-specific attribute (VSA) TrafficSelector-class, which is received from
the AAA server. The PDIF's Session Manager passes the selected traffic class configuration from its AAA Manager to
its IPSec Manager, which then sends the traffic selectors to the UE in the TSr for all CHILD SAs in the call. If no
matching traffic selector classes or traffic selectors have been configured on the PDIF, or if the PDIF does not receive
the TrafficSelector-class attribute from the AAA server, or if the value of the received TrafficSelector-class attribute is
0, the PDIF returns the default traffic selector to the UE in the TSr, which allows all inbound traffic.
The PDIF saves the traffic class configuration in each call during call setup. Configuration changes made to the existing
traffic class configuration will apply to new calls only. There is no hard limit to the maximum number of allowed traffic
classes, but the recommended limit is 50.
When incoming traffic from a UE does not match any of the configured traffic selectors, the PDIF does not reject the
traffic. Instead, the PDIF keeps a per-call counter to record the number of packets that do not match the configured
traffic selectors. Outgoing traffic from the PDIF to the UE is not subject to traffic selection or checking.
Selective Diameter Profile Update Request Control
For mobile IP calls, the Selective Diameter Profile Update Request Control feature allows WiFi data-only sessions to
co-exist with VoIP sessions on the PDIF platform.
When the PDIF is accessed by voice-enabled devices, it needs to interact with the HSS in order for a subscriber session
to access the IP core network. When the PDIF is accessed by data-only devices, there is no need to interact with the
HSS.
This feature is used to identify which subscriber sessions need to have the PDIF and the HSS exchange Diameter Profile
Update Request (PUR) and Profile Update Answer (PUA) messages, and allows the PDIF to handle the call setup for a
data-only client without having to interact with the HSS.
Selective PUR profiles on the AAA server are mapped to subscribers during AAA authentication via the Radius vendor-
specific attribute (VSA) FMC-Type. FMC-Type has these possible values: voice or data. When the AAA server sets the
FMC-Type value to voice, the PDIF and the HSS exchange PUR and PUA messages. When the AAA server sets the
FMC-Type value to data, the PDIF and the HSS do not exchange PUR and PUA messages.
This feature is enabled by default and requires no configuration.