Cisco ASR 5000 Series, Обзор продукта

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Mobility Management Entity Overview
SAE Network Summary ▀
Cisco ASR 5000 Series Product Overview ▄
OL-22938-02
Serving Gateway (S-GW)
For each UE associated with the EPS, there is a single S-GW at any given time providing the following basic functions:
Terminates the interface towards E-UTRAN (S1-U)
Functions (for both the GTP-based and the PMIP-based S5/S8) include:
local mobility anchor point for inter-eNodeB handover
mobility anchoring for inter-3GPP mobility (terminating S4 and relaying the traffic between 2G/3G
system and PDN GW)
ECM-IDLE mode downlink packet buffering and initiation of network triggered service request
procedure
lawful intercept
packet routing and forwarding
transport level packet marking in the uplink and the downlink (e.g. setting the DiffServ Code Point)
Accounting
Handling of Router Solicitation and Router Advertisement messages if PMIP based S5 and S8 are used
MAG for PMIP based S5 and S8
PDN Gateway (P-GW)
For each UE associated with the EPS, there is at least one P-GW providing access to the requested PDN. If a UE is
accessing multiple PDNs, there may be more than one P-GW for that UE. The P-GW provides the following basic
functions:
Terminates the interface towards the PDN (SGi)
PGW functions (for both the GTP-based and the PMIP-based S5/S8) include:
per-user packet filtering (e.g. deep packet inspection)
lawful intercept
UE IP address allocation
UL and DL service level charging, gating control, and service level rate enforcement
DL rate enforcement based on AMBR (Aggregate Max Bit Rate) and based on the accumulated MBRs
of the aggregate of SDFs with the same GBR QCI
DHCPv4 and DHCPv6 functions (client, relay and server)
LMA for PMIPv6