Basic Ingredients of Network Management Woraphon Lilakiatsakun

Basic components Fig 3-1

Network devices A NE (network element) must offer a management interface for management purposes Allow managing system to send requests ( configure, retrieve statistical data and etc) Send information (response and unsolicited ) Manager – a managing application who in charge of the management Agent – a NE who support the manager by responding its requests

Manager-agent communication Fig 3-2

Management agent Consists of 3 parts A management interface A Management Information Base The core agent logic

Management interface Support a management protocol that define rule of conversation Communication between the managed network element For example To open management session To request to retrieve statistical data To request to change configuration

Management Information Base (MIB) Conceptual data store (management information) that contain management view of devices A type of database used to manage the devices in a communications network. It comprises a collection of objects in a (virtual) database used to manage entities (such as routers and switches) in a network. (Ref. from wikipedia)

MIB related standard RFC 1155 RFC 1157 RFC 1213 Structure and Identification of Management Information for TCP/IP based internets RFC 1157 Simple Network Management Protocol RFC 1213 Management Information Base for Network Management of TCP/IP-based internets

MIB – OID Tree OID = 1.3.6.1 (internet) OID = 1.3.6.1.4.1.2682.1 (dpsAlarmControl)

Core agent logic Translates between the operation of the management interface, MIB, and actual device Ex. Translate the request to “retrieve a counter” into internal operation that read out a device hardware register. Additionally, it can include more management functions that offload the processing required by management app. Pre-correlated raw events before sent out

An anatomy of management agent Fig 3-4

Management information (1/2) The version of installed software To decide which devices need to have new software Utilization of port Whether capacity upgrades are necessary Environmental data (temperature and voltage) Ensuring that a device is not overheating Fans What is causing the temperature to rise

Management information (2/2) Packet counters for different interfaces Whether the network is under a certain type of attacks (DoS) Protocol timeout parameter To fine tune network communication performance Firewall rules Security purposes others ?

Managed object (MO) Refer to “ a chunk of management information that exposes one of the real world aspects” Ex. MO could represent a device fan along with its operational state, a port on a line card along with a set of statistical data MO could be a MIB object in SNMP a parameter in a CLI (command-line interface) An element of an XML document in web-based management interface

Not all aspects in the real world are modeled Color of devices Real world object that MO represents is referred to as the “real resource” Since management information in MIB represents real resource When querying the MIB for MO representing a packet counter 3 times, the value returned will be different

Basic parts of network management - refined Fig 3-6

The Management System Tools to manage the network monitor the network Service provisioning system Craft terminal In fact, management system is different from management applications But often we can use both as the same meaning

Manager/agent reference diagram Fig 3-8

Caching MIB Fig 3-9

The Management network Networks for carrying traffic of subscriber or end user are referred as “production network” Networks for carrying management traffic are referred as “management network” Both can be physically separate networks or they can share the same physical network

Connecting a craft terminal to a managed device Fig 3-10

Connecting to multiple devices through a terminal server Fig 3-11

Dedicated Vs Shared Management and Production networks Fig 3-12

Pros of a dedicated management network Reliability Congestion or network failure occurs somewhere in the network, it makes the devices hard to reach Also hard to find out what it happen Interference avoidance Compete with production traffic May interfere high QoS services (voice ,video streaming) Ease of network planning No need to consider on management traffic Security Hard to attack and more secure

Cons of a dedicated management network Cost and overhead Addition cost for a management network No reasonable alternative Some devices do not provide a physical connection for another usage DSL router cannot be connected with two physical links

Final word Cost is the huge disadvantage So, the management network is needed only critical area Backbone of service providers or big enterprises) Hybrid solution Generally, it shares over production networks Only critical segments are used as dedicated networks

Managing the management The management support org. is responsible for making sure that the network is being run efficiently and effectively These tasks must be performed Monitoring the network for failures Diagnosing failures and communication outages Planning and carrying out repairs Provisioning new services and adding/removing users

Keeping an eye on performance of the network Taking preventive measure Planning network upgrades Increase capacity Planning network topology and buildout Ensure that the network will meet future demand

Organization structure Network planning Analyzing network usage and traffic patterns and planning network build out Network operation Keeping the network running and monitoring the network failures Network administration Installing new devices / software Customer (user) management Interacting with the customers

Other thing are needed Establishment of process and operational policies, documentation of operational procedures Well-defined procedures Well-defined workflow Make management consistent and efficient Collection of audit trails Automatically logging activities of operations

Network documentation Must be accurate and up-to-date Important for network planning and software upgrades Identify some discrepancies Reliable backup and restore procedures Bring network back to live again in case of disaster Security emphasis Networks potentially most vulnerable from the inside Limit the damage that can cause by one person

Management life cycle Plan Before the network system starts During the network system is running

Management life cycle Deploy Operate Decommission Installation of the equipment Bootstrap mechanism to allow a device to obtain and IP address and have layer2 or 3 connectivity Operate Monitoring/troubleshooting/performance tuning and etc Decommission Old equipments (old technology) will be replace

TMN-layer: a management hierarchy reference model

Management layer TMN (telecommunication Management network) Network element Element management Network management Service management Business management

Network element It means “the management agent “ It involves with the management functionality Communication pattern (protocols)

Element management Involve managing the individual devices and keep them running Functions such as to view and change a network element’s configuration To monitor alarm messages emitted from elements To instruct network elements to run self-test

Network management Concern with keeping the network running as a whole (end-to-end) Monitoring that involves ensuring that data flow to reach destination with acceptable throughput and delay Managing multiple devices in a concerted fashion

Service management Managing the services that the network provides and ensuring those services are running smoothly Let’s think as ISP (Internet service provider) ?

Business management Billing and invoicing Help desk management Business forecasting Etc ?