Cisco Cisco Packet Data Gateway (PDG)
HNB Gateway in Wireless Network
Features and Functionality - Base Software ▀
HNB-GW Administration Guide, StarOS Release 16 ▄
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Congestion Control and Management Support
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:
Congestion Condition Thresholds: Thresholds dictate the conditions for which congestion control is enabled
and establishes limits for defining the state of the system (congested or clear). These thresholds function in a
way similar to operation thresholds that are configured for the system as described in the Thresholding
Configuration Guide. The primary difference is that when congestion thresholds are reached, a service
congestion policy and an SNMP trap, starCongestion, are generated.
way similar to operation thresholds that are configured for the system as described in the Thresholding
Configuration Guide. The primary difference is that when congestion thresholds are reached, a service
congestion policy and an SNMP trap, starCongestion, are generated.
A threshold tolerance dictates the percentage under the configured threshold that must be reached in order for
the condition to be cleared. An SNMP trap, starCongestionClear, is then triggered.
the condition to be cleared. An SNMP trap, starCongestionClear, is then triggered.
Port Utilization Thresholds: If you set a port utilization threshold, when the average utilization of all
ports in the system reaches the specified threshold, congestion control is enabled.
Port-specific Thresholds: If you set port-specific thresholds, when any individual port-specific
threshold is reached, congestion control is enabled system-wide.
Service Congestion Policies: Congestion policies are configurable for each service. These policies dictate how
services respond when the system detects that a congestion condition threshold has been crossed.
Important:
For more information on Congestion Control support, refer Congestion Control chapter in System
Administration Guide.
DHCP Interface Support Between HNB-GW and HMS
DHCP interface support at HNB-GW is provided to allocate IP address to HNB using DHCP procedure. Without this
support IP address is allocated using locally configured IP pool. HNB connects to HNB Security Gateway (Se-GW) via
IPSec tunnel. During IPSec tunnel establishment, HNB Se-GW allocates IP address to HNB. Femtocell provisioning
system needs HNB IP address. This is achieved by co-locating this system with DHCP server. HNB Se-GW then uses
DHCP procedure to allocate IP address to HNB.
support IP address is allocated using locally configured IP pool. HNB connects to HNB Security Gateway (Se-GW) via
IPSec tunnel. During IPSec tunnel establishment, HNB Se-GW allocates IP address to HNB. Femtocell provisioning
system needs HNB IP address. This is achieved by co-locating this system with DHCP server. HNB Se-GW then uses
DHCP procedure to allocate IP address to HNB.
Following is a typical message flow when HNB-GW performs as DHCP proxy:
1. HNB initiates IKE transaction by sending IKE SA INIT message to share encryption parameters.
2. Se-GW on HNB-GW responds with IKE SA INIT to confirm encryption parameters and the nonce.
3. HNB sends IKE Auth Request and includes IDi, IDr and configuration payload to request the IP address. IDi is
2. Se-GW on HNB-GW responds with IKE SA INIT to confirm encryption parameters and the nonce.
3. HNB sends IKE Auth Request and includes IDi, IDr and configuration payload to request the IP address. IDi is
the IKE ID of HNB-GW.
4. HNB-GW initiates Authentication with AAA Server. HNB and AAA server exchange EAP messages.
5. Finally AAA server confirms successful authentication of HNB to HNB-GW and Subscriber template is selected
5. Finally AAA server confirms successful authentication of HNB to HNB-GW and Subscriber template is selected
and aaa-data is returned to SessMGR by AAAMGR which contains necessary configuration and AAA returned
values.
values.
6. HNB-GW, as with previous EAP messages, relays EAP success over IKE Auth to HNB. Steps 4, 5 and 6 are not
performed in case of certificate based authentication.
7. HNB then initiates IKE Auth request to authenticate the SA. HNB-GW selects the IP address allocation method
using the configuration from AAA-data. Method is configured to be DHCP-proxy in subscriber template. To