Hello everyone!
If you've managed wireless base stations, you've had alarms. Alarms may cause a lot of trouble or even cause network interruption. Therefore, today, I want to introduce the classification and composition of alarms.
What is an alarm?
An alarm is reported to the element management system (EMS) when a device incurs a fault or an exception that needs to be rectified manually or using automation devices. An alarm has two states: generated and cleared. If an alarm is generated, it must be cleared.
What are the types of alarms?
Alarms are classified into the following types based on resource modules:
Node Alarms
GBTSFunction Alarms
NodeBFunction Alarms
eNodeBFunction Alarms
gNodeBFunction Alarms
RFAFunction Alarms
Resource Module of a Base Station
Base stations can be classified into separate-MPT base stations, co-MPT base stations, and single-mode base stations, based on function deployment. These base stations can be configured as the following NE types:
For a 3900 series base station, the value can be BTS3900, BTS3900 WCDMA, BTS3900 LTE, and BTS3900 5G.
For a 5900 series base station, the value can be BTS5900, BTS5900 WCDMA, BTS5900 LTE, and BTS5900 5G.
Among these values, BTS3900 or BTS5900 indicates a co-MPT base station; BTS3900 WCDMA or BTS5900 WCDMA indicates a UMTS base station; BTS3900 LTE or BTS5900 LTE indicates an LTE base station; BTS3900 5G or BTS5900 5G indicates a 5G base station.
These NEs consist of resource modules such as Node, GBTSFunction, NodeBFunction, eNodeBFunction, gNodeBFunction, and RFAFunction. In a base station, the Node resource module manages device and transmission resources while the GBTSFunction, NodeBFunction, eNodeBFunction, gNodeBFunction, and RFAFunction resource modules manage radio resources of their corresponding modes. The following figure shows examples of relationship between the base station type, NE type, and resource module.
Figure 1 Relationship between the base station type, NE type, and resource module (BBU3900 is used as an example).
NOTE
1. A GSM base station is either an eGBTS or a GBTS. A GBTS is managed by a BSC, and therefore the preceding relationship structure does not apply to the GBTS.
2. RFAFunction is used only in the LampSite solution, and supports only co-MPT base stations. It performs remote transmission and amplification of RF signals, and complies with the 3GPP repeater radio transmission and reception protocol (GSM: 3GPP TS 51.026, UMTS: 3GPP TS 25.106, and LTE: 3GPP TS 36.106).
Alarm Composition
Base stations share the same fault management architecture and their alarms consist of Node alarms and Function alarms of corresponding modes. Node alarms consist of device alarms and transmission alarms, and Function alarms are radio alarms, as shown in the following figure.
Co-MPT base station alarms consist of Node alarms, GBTSFunction alarms, NodeBFunction alarms, eNodeBFunction alarms, gNodeBFunction alarms, and RFAFunction alarms. When a co-MPT base station works in one or multiple modes, its alarms consist of Node alarms and Function alarms of the corresponding modes, as shown in the following figure. For example, when a co-MPT base station works in GO mode, its alarms consist of Node alarms and GBTSFunction alarms.
A GSM base station is either an eGBTS or a GBTS. A GBTS is managed by a BSC, whereas an eGBTS is not. Therefore, reference for GBTS alarms differs from that for eGBTS alarms. For details, see GBTS alarm reference in BSC6900 GSM Product Documentation or BSC6910 GSM Product Documentation. eGBTS alarms consist of Node alarms and GBTSFunction alarms.
NodeB alarms consist of Node alarms and NodeBFunction alarms.
eNodeB alarms consist of Node alarms and eNodeBFunction alarms.
gNodeB alarms consist of Node alarms and gNodeBFunction alarms.
Figure 2 Fault management architecture
NOTE
BTS3900[a] and BTS5900[a] indicate the resource type of a co-MPT base station, and BTS3900[b] and BTS5900[b] indicate the resource model of an eGBTS.
Alarm Severity
Impact of an alarm on service quality. There are four alarm severity levels: critical, major, minor, and warning.
Critical: A critical alarm affects system services. If a critical alarm is generated, immediate actions are necessary even when the fault occurs during non-working hours.
Major: A major alarm affects service quality and requires immediate actions during working hours.
Minor: A minor alarm may affect service quality. Therefore, it needs to be handled or observed as required to prevent more serious faults.
Warning: A warning alarm indicates a potential error that may affect service quality. It requires different actions depending on errors.
These are the introductions I shared about alarms. Welcome to read and comment!
