Tik-109/110.300
Telecommunications architectures:
Network management
Hannu H. KARI/Helsinki University of Technology (HUT) TML-laboratory/CS/HUT
Agenda
Telecom management area
Difference between fixed and mobile networks Network management principles
Telecommunications management network (TMN) Telecom requirements
Protocols
Fault management
Configuration management Accounting/charging
Performance management Security management
Telecom management area
• MS - Mobile Stations BTS - Base Transceiver Station BSC - Base Station Controller
• MSC - Mobile Switch Center HLR - Home Location Register
• VLR - Visiting Location Register OMC - Operation and Maintenance Center
Difference between fixed and mobile networks
• Fixed telecom network
• Backward compatibility:
• tens of years
• Complex part:
• Copper wires
• Growth rate:
• Very moderate
• Load predictability:
• Quite stable, varies on time
• Mobile telecom network
• Backward compatibility:
• 10 years
• Complex part:
• Radio network
• Radio capacity
• Location of base stations
• Growth rate:
• Very fast
• Load predictability:
• Big variance due to mobility
Network management
principles
Network management principles
• Network Management Station(s):
• The network management station runs the network
management application that gathers information about
managed devices from the management agent which resides within a managed device.
• The network management application typically must process large amounts of data, react to events, and prepare relevant information for display. It usually has a control console with a GUI interface which allows the operator to view a
graphical representation of the network, control managed devices on the network and program the network
management application.
Network management principles
• Network management station (contd)
• Some network management applications can be programmed to react to information collected from
management agents and/or set thresholds with the following actions:
• Perform tests and automatic corrective actions (reconfiguration, shutdown of a managed device)
• Logging network events
• Present status information and alerts to operator
• Managed Devices:
• A managed device can be any type of node residing on a network, such as a computer, printer or router. Managed devices contain a management agent.
Network management principles
• Management agents:
• Provides information about the managed device to the network management application(s) and may also accept control information.
• Network management protocol:
• Protocol used by the network management application(s) and the management agent to exchange management information.
• Management Information:
• The information that is exchanged between the network management application(s) and the management agents that allows the monitoring and control of a managed device.
Telecommunications
management network (TMN)
• The telecommunications management network (TMN) provides a framework for achieving interconnectivity and communication across heterogeneous operating systems and telecommunications networks.
• TMN was developed by the International
Telecommunications Union (ITU) as an infrastructure to support management and deployment of dynamic
telecommunications services.
TMN architecture
• Network management is parallel to user
data transfer
TMN architecture
• TMN architecture and interfaces, defined by ITU, build on existing OSI standards
• common management information protocol (CMIP)—defines management services exchanged between peer entities
• guideline for definition of managed objects
(GDMO)—provides templates for classifying and describing managed resources
• abstract syntax notation one (ASN.1)—provides syntax rules for data types
• open systems interconnect reference model—defines the seven-layer OSI reference model
• Questions/issues: multivendor, interoperable, extensible, scalable, and object-oriented
TMN architecture
• OS: performs operations system functions
• MD: performs mediation between local TMN interfaces and the OS information model
• QA: translates between TMN and non–TMN interfaces
• NE: network element containing manageable information
• WS: workstation
• DCN: data communication network
TMN architecture
• Interfaces
• Q3 Interface
• Q3 is the only interface that QAs, MDs, or NEs may use to communicate directly with the OS.
• If a QA or NE does not use the Q3 interface, it cannot communicate directly with the OS; Instead, it must communicate via an MD.
• Qx Interface
• Qx interface always operates with a MD.
• The MD can interpret between local management information provided by a Qx interface and the OS information provided by a Q3 interface.
Telecom requirements
• Network management needs
• Management protocols
• Network management should handle
• Fault management
• Configuration management
• Accounting/Charging
• Performance management
• Security management
• Remote access
Management protocols
• SNMP (Simple Network Management Protocol)
• Not so much in use in telecom world
• CMIP (Common Management Information Protocol)
• Proprietary
• Manufacturer’s own protocols or own enhancements on the standard protocols
• Protocol conversions needed
• E.g., CMIP <-> Proprietary protocol
SNMP
SNMP
• GET_NEXT_REQUEST
• Requests next object instance from a list from an agent
• GET_RESPONSE
• Returned answer to get_next_request, get_request, set_request
• GET_REQUEST
• Requests the value of an object instance from the agent
• SET_REQUEST
• Set the value of an object instance within an agent
• TRAP
• Send trap (event) asynchronously to network management application. Agents can send a trap when a condition has
occurred, such as change in state of a device, device failure or agent initialization/restart.
SNMP
• SNMPv1
• incorporated into many products and management platforms
• deployed by virtually all internetworking vendors
• well-suited for managing TCP/IP networks.
• SNMPv2
• has many unresolved issues (security, administrative needs)
• was supported by few vendors
=> will be skipped
• SNMPv3
• latest version for the next generation of SNMP functionality
• based upon the protocol operations, data types, and proxy support from SNMPv2
CMIP functions
• ACTION
• Request an action to occur as defined by managed object.
• CANCEL_GET
• Cancel an outstanding GET request.
• CREATE
• Create an instance of a managed object.
• DELETE
• Delete an instance of a managed object.
• GET
• Request the value of a managed object instance.
• SET
• Set the value of a managed object instance.
CMIP benefits over SNMP
• The major advantages of CMIP over SNMP
• CMIP variables not only relay information, but also can be used to perform tasks. This is impossible under SNMP.
• CMIP is a safer system as it has built in security that
supports authorization, access control, and security logs.
• CMIP provides powerful capabilities that allow management applications to accomplish more with a single request.
• CMIP provides better reporting of unusual network conditions
Protocol conversion
• Various protocols can be combined and
interoperate
Fault management
• Provides facilities that allow network managers to
discover faults in managed devices, the network, and network operation, to determine their cause and to take remedial action. To enable this, fault management
provides mechanisms to:
• Report the occurrence of faults
• Log reports
• Perform diagnostic tests
• Correct/repair faults (possibly automatically)
Configuration management
• Monitors network configuration information so that the effects of specific hardware and software can be
managed and tracked.
• It may provide the ability to initialize, reconfigure, operate and shut down managed devices.
• Remote download of new software and configuration
• One button download of software to entire network
Accounting/Charging
• Measures network utilization of individual users or groups to
• Provide information for billing purposes
• Regulate users or groups
• Help keep network performance at an acceptable level
Performance Management
• Measures various aspects of network performance
including the gathering and analysis of statistical data about the system so that it may be maintained at an acceptable level
• Performance management provides the ability to
• Obtain the utilization and error rates of network devices
• Provide a consistent level of performance by ensuring that devices have a sufficient capacity
Security Management
• Controls access to network resources so that
information can not be obtained without authorization by:
• Limiting access to network resources
• Providing notification of security breaches and attempts
Remote access
• Network elements (nodes) are distributed all over the network
• Management can be centralized
• One network management station can control the entire network
Multivendor network
• Can same network management system manage several vendors devices?
• Technically, yes
• E.g., SNMP has MIB (Management information base)
definitions that can be used in controlling network elements independent of manufacturer
• Politically, NO!
• Manufacturers do not like other companies to get internal information of their implementation
• Multivendor networks typically require multiple management systems
Links
• In English
• http://www.iec.org/tutorials/tmn/
• http://cybermanage.wipro.com/telecom.htm
• http://www.sei.cmu.edu/str/descriptions/network.html
• http://www.sei.cmu.edu/str/descriptions/cmip.html
• http://www.sei.cmu.edu/str/descriptions/snmp.html
• In Finnish
