|
Network technology has come a long way from the days of hubs and
10 BaseT Ethernet to complex multi-layered networks carrying voice, video and
data. It is seen that with emergence of technologies such as VoIP, VPN, MPLS
backbones and Wireless LANs, most organizations have adopted these technologies
for the benefit they offer. It is also seen that organizations are looking for
best-of-breed solutions leading to multi-vendor networks over a period of time.
Add to that, a complex myriad of technologies and the network becomes a
nightmare for the CIO to manage and maintain. Most CIOs are looking for panacea
in network management solutions that will assist their teams in ensuring that
the network is always available and performing optimally. Network management
gurus typically use the acronym FCAPS
(Fault/Configuration/Accounting/Performance/Security) which more or less sums up
the challenges of network management and expectations from a network management
tool.
Fault Management
Almost all network devices today are manageable (ie they have an intelligent
SNMP agent installed). This capability makes it very easy for a network
management system to discover and classify the device. In addition, the SNMP
agent provides additional information about the current status and connectivity
with other devices.
Fault management systems (FMS) are able to discover and model
the topology of complex network environments based on SNMP and other
technologies (Routing tables, ARP caches etc). They are able to poll devices and
receive traps to correctly depict the status on the topology map. In addition,
these solutions allow capabilities to automate response to common events, the
response typically being e-mail/SMS notifications, incident registration to a
service desk or running custom scripts. Such detailed information helps
administrators diagnose problems faster leading to reduced mean time to repair.
| Challenges
Addressed |
-
To understand device
connectivity (at Layer 2 and 3)
-
To ensure the network is
up and running
-
Proactively locate
faults in the network and rectify them before they impact end-users
-
To reduce the number of
symptomatic network
-
Handling faults as 'Incidents'
(as per ITIL best practice recommendations) and track the same till
resolution
|
Advanced fault management systems offer the most useful
functionality of event correlation and root cause analysis. This system
typically comprises in-built correlation logic and rule sets to correlate
multiple incoming events and provide a possible single root-cause. This allows
administrators to understand and diagnose network problems faster as compared to
chasing events that are symptomatic. For example, when an upstream device goes
down, all connected downstream device polls will generate failure messages.
Another common function that advanced fault management systems
perform today is mapping discovered IT infrastructure to IT services. SLAs
(based on availability and response times) can be attached to the IT services
rather than individual elements. This allows administrators to understand the
impact of a failing component on IT services and the relevant SLA that are
affected.
Configuration Management
Configuration management is a process that covers a wider range of IT
infrastructure and is not restricted only to network devices. Configuration
changes on network devices are required for a wide variety of reasons including
adding new boards to existing devices, firmware upgrades, manual
addition/removal of routes on a router etc. Configuration management mandates
that such changes be made only after relevant approvals from the CAB (Change
Advisory Board) or similar approving authority. This is done so that the impact
of the change on various IT and Business Services can be studied before actually
performing the change. Rollback procedures are also defined to minimize
disruption to services in case something goes wrong.
| Challenges
Addressed |
-
Being able to identify
performance bottlenecks in complex networks
-
Identification of
baseline behavior of the network with alerts only if the performance
is abnormal
-
Catering to performance
management for various subcomponents of the network including
utilization, response time, error rates etc
-
Being able to
proactively fix performance related issues with impact analysis
|
Configuration management solutions are also capable of reading
device configuration at periodic intervals and comparing it to the deployed
image to check for changes. Changes (if any) can be reported to the fault
management system and automated actions such as redeploying the original image
can be initiated. It is also important to ensure that unauthorized changes to
device configurations do not take place (by deploying stricter access control on
network devices).
Accounting Management
The primary challenges addressed by accounting management are-tracking
network utilization by application/end-user/department for the purpose of
chargeback; allocate appropriate network resources for business critical
applications/departments
Accounting management involves tracking each individual user's
utilization of network resources for the purposes of allocation of resources and
billing for their use of the network. This type of information helps a network
manager allocate the right kind of resources to users, as well as plan for
network growth. With the same information, the cost of transmitting messages
across the network can be computed and billed to the user if the traffic was
revenue bearing.
This type of management involves monitoring the login and logoff
records, and checking the network usage to determine a user's use of the
network. In addition, access privileges and usage quotas can be established and
checked against actual for accounting information.
Technology used for accounting management typically involves
probes/flow records to collect raw data related to traffic segregated by
user/application. This data is collected, analyzed and appropriate reports are
created to indicate the network resource usage. Accounting tools go a step
further by analyzing the collected data and providing billing invoices to
business units based on pre-defined chargeback information. Page(s) 1 2
|