1. Introduction
In this tutorial, we’ll study the FCAPS model for network management. Managing a modern network is not an easy task. Current networks are highly connected, and multiple services depend on them to be provided. Thus, network managers and operators must attempt several maintainability aspects to keep services online and with proper quality-of-service levels.
In this context, we’ll investigate FCAPS, a network management model. FCAPS presents five working levels for network management: Fault, Configuration, Accounting, Performance, and Security. So, we should consider specific processes and attention points for each one of these management levels.
In the following section, we’ll have some background concepts on network management. Then, we’ll particularly study the working levels of the FCAPS model. Finally, we’ll have a systematic summary and present final remarks.
2. Network Management
In short, network management consists of the processes executed to keep a network satisfactorily operational. By satisfactorily, we mean a network that successfully delivers traffic considering some established performance parameters (for example, maximum delay or minimum throughput).
The International Organization for Standardization (ISO) released the FCAPS model in the early 1980s. The main objective of creating this model was to guide the development of network management solutions and frameworks.
To do that, the ISO indicates five working levels of network management: Fault, Configuration, Accounting, Performance, and Security. So, network management developers could precisely define on which working levels their solutions and frameworks operate.
Some network management protocols, frameworks, and models that are based on FCAPS to get better organized are:
- Telecommunications Network Management (TMN): a generic management architecture that comprises four main management layers (element, network, service, and business). Each management layer includes processes for all the FCAPS working levels
- Common Management Information Protocol (CMIP): a model based on managed elements that allow providers to control the networks. This model goes through all five working levels of FCAPS
- Common Management Information Service (CMIS): a model to define the service interface for the CMIP elements. Naturally, as CMIP does, the model goes through all the working levels of FCAPS
Each working level of FCAPS has relevant characteristics to be explored. Thus, in the following section, we’ll study these levels in detail.
3. The FCAPS Model
As previously stated, the FCAPS model aims to provide a guide for developers and operators on how to manage a networked environment. This model approaches management holistically, defining five working levels: Fault, Configuration, Accounting, Performance, and Security.
So, in this section, we’ll see the most relevant characteristics of the FCAPS’ working levels.
3.1. Fault Management
In a network, it is not unusual for faults happening. Faults will eventually occur, even adopting several preventive actions against them. In this way, fault management in FCAPS aims to detect these faults and mitigate their consequences, in addition to recovering the networked system.
To deal with faults, the FCAPS model proposes a five-step cycled workflow:
In the fault management workflow, detection means the ability to identify that something goes wrong in the system. Based on the detection, the next step consists of verifying the part of the system affected by the detected fault, which we call diagnosis and isolation. Thus, potential problems and consequences of the fault are measured in the step called correlation and aggregation.
After that, the developers and operators can start working on mitigating and solving the problem, making the system fully functional. We call this step restoration. Finally, in the resolution step, the system is checked to confirm that the fault got fixed.
3.2. Configuration Management
Managing the configuration of networked systems is guaranteeing that they will work as expected in their lifecycle, even when updates, upgrades, and scaling processes happen.
Configuration management deals with hardware and software:
On the hardware side, for example, we have inventory management that comprises all the machinery available for a networked system. Also, we have allocation management refereeing to the best physical placement of hardware resources and upgrading and scaling management to provide the proper amount of computational resources for the networked system.
On the software side, we should attempt to find the best hardware machine for running the required programs regarding execution support and performance. Moreover, operators should manage the running software versioning, keeping it updated. Finally, configuring the system also includes defining which operators will have access to each part of it.
3.3. Accounting Management
Accounting management aims to optimize the distribution of resources among the network clients. Thus, we can understand accounting management as administrative tasks involving network managers, operators, and clients.
The following figure depicts, on a high level, some tasks of accounting management:
A particular task of accounting management is creating an inventory of all available network resources. In this way, while routines executed in configuration management update the machinery in this inventory, the accounting management focuses on updating the inventory itself.
Accounting management also works on billing management. So, to do that, operators and managers typically generate statistics on clients’ registers, their network usage, and the impact of different network usage profiles.
Finally, it is also a task of accounting management to determine the proper permissions and access rights of each client in the network.
3.4. Performance Management
As the name suggests, performance management works on monitoring and trying to improve the overall performance of a network. We can see performance improvements in different manners, such as maximizing throughput, minimizing latency, and avoiding bottlenecks.
The next figure show some usual monitoring routines and performance improvement actions of performance management:
The central objective of performance management is improving the provided quality of service and experience for the clients. But, more than that, performance management enables the managers and operators to understand the network necessities as the number of clients grows or decreases or the service level agreements change.
3.5. Security Management
The main idea of security management is controlling the access to the resources and equipment of a network, mainly the sensitive ones. By avoiding improper accesses and modifications in the network, the operators and managers both keep the network active and the clients secure.
Examples of typical attacks that may occur in a network are denial of service, man-in-the-middle, and DNS poisoning, among others.
Security management starts in the core network itself. Relevant actions to securing a network consist of deploying network functions tailored to identify and mitigate attacks.
Security function examples are intrusion detection and prevention systems, firewalls, antivirus, etc. The figure below shows a deployment of these functions in a simple network:
Furthermore, encrypting sensitive network traffic is an important security measure frequently adopted.
4. Systematic Summary
Managing networks is a complex but crucial task. Modern networks provide multiple services to thousands of clients. These clients, however, require certain levels of quality of service and experience and typically establish agreements before subscribing to a networked service.
Networked service providers, in turn, hire teams of network managers and operators to maintain their services according to the established agreements. That is the point where the FCAPS emerges.
FCAPS is a network management model that encompasses five working levels: Fault, Configuration, Accounting, Performance, and Security. These working levels present several practices to accomplish network quality objectives and enforce agreements and policies.
In this way, the following table briefly summarizes some relevant characteristics of the FCAPS working levels:
Brief Definition
Main Practices
Fault
This working level aims to avoid faults in the networked systems, as well as mitigate consequences when they occur
Detection; Diagnosis/Isolation; Correlation/Aggregation; Restoration; Resolution
Configuration
At this working level, the networked systems are configured for properly working in their lifecycle
Inventory Update; Devices Configuration; Software Deployment and Updates
Accounting
Accounting tackles administrative tasks for networked systems and optimizes them for their users
Machinery Inventory Management; Generate Network Usage Statistics; Generate Client Statistics; Billing
Performance
This working level aims to improve the overall network performance, as well as the performance of the services running on it
Monitor Machines Overloads; Monitor Network Metrics; Monitor Quality of Service; Run Optimization Algorithms
Security
The working level that aims to control the access to systems’ resources and keep them safe from malicious actions
Analyze incoming and outgoing traffic; Analyze running processes; Keep services available; Encrypt sensitive data
5. Conclusion
In this tutorial, we investigated the FCAPS model for network management. At first, we studied some basic concepts of network management. Thus, we examined the FCAPS model, attempting each of its working levels. Finally, we reviewed the presented concepts in a systematic summary.
We can conclude that network management is an essential task to keep networked services available. FCAPS, in turn, comes as a guide for comprehensively managing networks. So, adopting the practices suggested by the FCAPS model makes the networks more maintainable, providing networked systems with higher quality.