Дорожная карта для Cisco Cisco Packet Data Gateway (PDG)
HRPD Serving Gateway Overview
Features and Functionality - Base Software ▀
Cisco ASR 5000 Series Product Overview ▄
OL-22937-01
The main A10' connection (SO59) carries PPP traffic including EAP-over-PPP for network authentication. The UE
performs LCP negotiation with the HSGW over the main A10' connection. The interface between the e-PCF and HSGW
uses GRE encapsulation for A10's. HDLC framing is used on the Main A10 and SO64 auxiliary A10's while SO67 A10
connections use packet based framing. After successful authentication, the HSGW retrieves the QoS profile from the
3GPP HSS and transfers this information via A11' signaling to the e-PCF.
performs LCP negotiation with the HSGW over the main A10' connection. The interface between the e-PCF and HSGW
uses GRE encapsulation for A10's. HDLC framing is used on the Main A10 and SO64 auxiliary A10's while SO67 A10
connections use packet based framing. After successful authentication, the HSGW retrieves the QoS profile from the
3GPP HSS and transfers this information via A11' signaling to the e-PCF.
Multiple PDN Support
Enables an APN-based user experience that enables separate connections to be allocated for different services including
IMS, Internet, walled garden services, or offdeck content services.
IMS, Internet, walled garden services, or offdeck content services.
The MAG function on the HSGW can maintain multiple PDN or APN connections for the same user session. The MAG
runs a single node level Proxy Mobile IPv6 tunnel for all user sessions toward the LMA function of the PDN GW.
When a user wants to establish multiple PDN connections, the MAG brings up the multiple PDN connections over the
same PMIPv6 session to one or more PDN GW LMA's. The PDN GW in turn allocates separate IP addresses (Home
Network Prefixes) for each PDN connection and each one can run one or multiple EPC default & dedicated bearers. To
request the various PDN connections, the MAG includes a common MN-ID and separate Home Network Prefixes,
APN's and a Handover Indication Value equal to one in the PMIPv6 Binding Updates.
runs a single node level Proxy Mobile IPv6 tunnel for all user sessions toward the LMA function of the PDN GW.
When a user wants to establish multiple PDN connections, the MAG brings up the multiple PDN connections over the
same PMIPv6 session to one or more PDN GW LMA's. The PDN GW in turn allocates separate IP addresses (Home
Network Prefixes) for each PDN connection and each one can run one or multiple EPC default & dedicated bearers. To
request the various PDN connections, the MAG includes a common MN-ID and separate Home Network Prefixes,
APN's and a Handover Indication Value equal to one in the PMIPv6 Binding Updates.
Performance: In the current release, each HSGW maintains a limit of up to 3 PDN connections per user session.
PPP VSNCP
VSNCP offers streamlined PPP signaling with fewer messages to reduce connection set-up latency for VoIP services
(VORA). VSNCP also includes PDN connection request messages for signaling EPC attachments to external networks.
(VORA). VSNCP also includes PDN connection request messages for signaling EPC attachments to external networks.
Vendor Specific Network Control Protocol (VSNCP) provides a PPP vendor protocol in accordance with IETF RFC
3772 that is designed for PDN establishment and is used to encapsulate user datagrams sent over the main A10'
connection between the UE and HSGW. The UE uses the VSNCP signaling to request access to a PDN from the
HSGW. It encodes one or more PDN-ID's to create multiple VSNCP instances within a PPP connection. Additionally,
all PDN connection requests include the requested Access Point Name (APN), PDN Type (IPv4, IPv6 or IPv4/v6) and
the PDN address. The UE can also include the Protocol Configuration Options (PCO) in the VSNCP signaling and the
HSGW can encode this attribute with information such as primary/secondary DNS server or P-CSCF addresses in the
Configuration Acknowledgement response message.
3772 that is designed for PDN establishment and is used to encapsulate user datagrams sent over the main A10'
connection between the UE and HSGW. The UE uses the VSNCP signaling to request access to a PDN from the
HSGW. It encodes one or more PDN-ID's to create multiple VSNCP instances within a PPP connection. Additionally,
all PDN connection requests include the requested Access Point Name (APN), PDN Type (IPv4, IPv6 or IPv4/v6) and
the PDN address. The UE can also include the Protocol Configuration Options (PCO) in the VSNCP signaling and the
HSGW can encode this attribute with information such as primary/secondary DNS server or P-CSCF addresses in the
Configuration Acknowledgement response message.
Congestion Control
The congestion control feature allows you to set policies and thresholds and specify how the system reacts when faced
with a heavy load condition.
with a heavy load condition.
Congestion control monitors the system for conditions that could potentially degrade performance when the system is
under heavy load. Typically, these conditions are temporary (for example, high CPU or memory utilization) and are
quickly resolved. However, continuous or large numbers of these conditions within a specific time interval may have an
impact the system‘s ability to service subscriber sessions. Congestion control helps identify such conditions and invokes
policies for addressing the situation.
under heavy load. Typically, these conditions are temporary (for example, high CPU or memory utilization) and are
quickly resolved. However, continuous or large numbers of these conditions within a specific time interval may have an
impact the system‘s ability to service subscriber sessions. Congestion control helps identify such conditions and invokes
policies for addressing the situation.
Congestion control operation is based on configuring the following: