для Cisco Cisco ASR 5000
Serving GPRS Support Node (SGSN) Overview
▀ Features and Functionality
▄ SGSN Administration Guide, StarOS Release 18
The system supports Threshold Crossing Alerts for certain key resources such as CPU, memory, number of sessions etc.
With this capability, the operator can configure threshold on these resources whereby, should the resource depletion
cross the configured threshold, a SNMP Trap would be sent.
With this capability, the operator can configure threshold on these resources whereby, should the resource depletion
cross the configured threshold, a SNMP Trap would be sent.
The following thresholding models are supported by the system:
Alert: A value is monitored and an alert condition occurs when the value reaches or exceeds the configured high
threshold within the specified polling interval. The alert is generated then generated and/or sent at the end of
the polling interval.
the polling interval.
Alarm: Both high and low threshold are defined for a value. An alarm condition occurs when the value reaches
or exceeds the configured high threshold within the specified polling interval. The alert is generated then
generated and/or sent at the end of the polling interval.
generated and/or sent at the end of the polling interval.
Thresholding reports conditions using one of the following mechanisms:
SNMP traps: SNMP traps have been created that indicate the condition (high threshold crossing and/or clear) of
each of the monitored values.
Generation of specific traps can be enabled or disabled on the chassis. Ensuring that only important faults get displayed.
SNMP traps are supported in both Alert and Alarm modes.
SNMP traps are supported in both Alert and Alarm modes.
Logs: The system provides a facility called threshold for which active and event logs can be generated. As with
other system facilities, logs are generated Log messages pertaining to the condition of a monitored value are
generated with a severity level of WARNING.
generated with a severity level of WARNING.
Logs are supported in both the Alert and the Alarm models.
Alarm System: High threshold alarms generated within the specified polling interval are considered
“outstanding” until a the condition no longer exists or a condition clear alarm is generated. “Outstanding”
alarms are reported to the system's alarm subsystem and are viewable through the Alarm Management menu in
the Web Element Manager.
alarms are reported to the system's alarm subsystem and are viewable through the Alarm Management menu in
the Web Element Manager.
The Alarm System is used only in conjunction with the Alarm model.
Important:
For more information on threshold crossing alert configuration, refer to the Thresholding
Configuration Guide.
Tracking Usage of GEA Encryption Algorithms
GPRS encryption algorithm (GEA) significantly affects the SGSN processing capacity based on the GEAx level used -
GEA1, GEA2, or GEA3.
GEA1, GEA2, or GEA3.
Operators would like to be able to identify the percentages of their customer base that are using the various GEA
encryption algorithms. The same tool can also track the migration trend from GEA2 to GEA3 and allow an operator to
forecast the need for additional SGSN capacity.
encryption algorithms. The same tool can also track the migration trend from GEA2 to GEA3 and allow an operator to
forecast the need for additional SGSN capacity.
New fields and counters have been added to the output generated by the
show subscribers gprs-only|sgsn-
only summary
command. This new information enables the operator to track the number of subscribers capable of
GEA0-GEO3 and to easily see the number of subscribers with negotiated GEAx levels.
VLR Pooling via the Gs Interface
VLR Pooling, also known as Gs Pooling, helps to reduce call delays and call dropping, when the MS/UE is in motion,
by routing a service request to a core network (CN) node with available resources.
by routing a service request to a core network (CN) node with available resources.