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Network Management: Managing that Network

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VoicenData Bureau
New Update

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.

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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.

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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.

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

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.

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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.

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).

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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

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

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Challenges

Addressed

  • Ensuring that all

    network devices have a standard configuration

  • Minimize the

    vulnerability of network devices related to firmware upgrades

  • Maintain a process

    oriented approach for configuration changes including necessary

    approvals

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.

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FMS enables

administrators to understand and diagnose network problems faster than

chasing events that are symptomatic

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.

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Performance Management



Complex networks such as VoIP or MPLS cores require a finer degree of
performance monitoring that provides the ability to collect data from vendor

provided SNMP MIBs to report on parameters such as jitter, MOS (Mean Opinion

Score-a common indicator of voice quality in VoIP networks) and

volume/congestion levels in a CoS (Class of Service indicating a dedicated

channel with QoS attributes in an MPLS based VPN). These reports are provided

out-of-box by advanced network performance management systems.

Network performance management solutions also aid the

administrator in locating performance bottlenecks by providing intelligent 'At-a-Glance'

reports that show crucial device performance metrics on a single page. Decisions

on which metrics best reflect the overall performance of the device are made in

consultation with industry experts. These solutions also offer the ability to

customize reports based on user requirements.

IT managers can also use the solutions to identify under

utilized and over utilized links. Advanced systems also offer 'what-if'

scenario simulators that allow administrators to gauge the growth in capacity

given the growth in demand. This is a very useful feature when rolling out new

applications.

Challenges

Addressed

  • Ensure secure access

    to network devices after requisite authorization with audit logs

  • Ensure security of

    data when it passes through public networks

  • Manage security

    incidents across network devices (routers /switches/firewalls/IDS/IPS

    )

  • Secure known

    vulnerabilities in protocols such as SNMP

Multiple network performance solutions are available in the

market ranging from freeware, open source to proprietary software. Most of these

solutions leverage SNMP agents on target devices to collect and chart

performance statistics of key parameters such as device utilization, link

utilization and error rates, availability and response times.

Security Management



Security Management is a vast domain on its own comprising threat management
(firewalls, anti-virus, anti-spyware, content inspection, vulnerability

management), identity and access management (user lifecycle management, single

sign on, access control) and security incident management (log consolidation,

data normalization, event correlation). Comprehensive security management suites

are available today to provide an integrated approach to managing security at

various touch points within the organization.

Vulnerabilities often exist at the network layer in the form of

firmware loopholes, badly configured SNMP access control and non-existent access

lists on critical devices. Solutions such as vulnerability scanners alleviate

this problem by providing a list of vulnerabilities and bad configurations.

These scanners obtain a list of the latest vulnerabilities from vendor websites.

Using these reports, administrators can take remedial actions such as upgrading

the firmware or modifying configurations.

Network

performance management solutions aid the administrator in locating

performance bottlenecks

Network security solutions also offer data security by means of

Virtual Private Networks (VPNs) that allow end users to securely access data

over public networks such as the Internet. IPSec protocols are standards-based

and provide the three factors needed for secure communications-authentication,

integrity, and confidentiality-even in large networks. The end-result is that

with IPSec-compliant products, you can build a secure VPN in any existing

IP-based network.

Multi-functional Solution



All said and done, network management is one of the oldest disciplines of IT
infrastructure management and is here to stay. Network management solutions have

come a long way from being just polling and charting tools to providing advanced

analytics to minimize downtime and brown-outs. Today, CIOs are expecting

solutions that provide integrated FCAPS functionality rather than a piecemeal

approach. They also expect these solutions to provide analytics in the form of

complex SLA reports, capacity planning information and root cause analysis to

ensure that the network is always available and performing optimally.

Rajendra Dhavale,



consulting director, CA India and SAARC



vadmail@cybermedia.co.in




Rajendra has over 18 years of experience.


A frequent speaker at industry seminars and technical conferences in India, he
is also constantly featured in IT/telecom publications.

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