Telecommunication Management Network, TMN* *Mani Subramanian “Network Management: Principles and practice”, Addison-Wesley, 2000.

Background Based on OSI CMIP/CMIS Address the interoperability of multi-vendor equipment used by different service providers and define standard interfaces Provide a framework for telecommunications network and service management Management goes beyond networks and network element to include managing services provided by service providers as well as business management

Trends In Telecommunications Globalizations and Deregulation End-to-end service involves multiple providers Demand for standards based network and service management (interoperability) Merge of telecom and datacom Need for Inter-working between management protocols to provide end-to-end management Evolution in protocols Need for flexible management architecture Competition Time-to market for new services Need for sound (flexible) architecture Focus on customer care (i.e., service quality) Decreasing margins (do more with less) Increase revenue (providing high quality services) while minimizing network operation costs

Example of Management (1) Trunk Testing System Trunk is a logical connection between two switching nodes Periodic measurement of loss and S/N of all trunks Failing threshold set for QoS; failing trunks removed out of service before the customer complains

Example of Management (2) Telephone Switch Traffic Traffic monitored at switch appearance Call blocking statistics obtained Traffic and call-blocking statistics provide data for planning Importance of Operations, administration, maintenance, and provisioning

TMN Conceptual Model TMN is conceptually a separate network Interfaces between the TMN and the Telecommunication network are formed by exchanges and transmission switches OSs (Operations Systems) perform most of the management functions and they are connected to TMN through a Data Communication Network (DCN) The DCN is used to exchange management information between OSs

TMN Objectives The basic concept behind a TMN is to: provide an organized architecture to achieve the interconnection between various types of OS’s and/or telecommunications equipment for the exchange of management information using an agreed architecture with standardized interfaces including protocols and messages The M.3010 recommendation defines “general architectural requirements for a TMN to support the management requirements of administration to plan, provision, install, maintain, operate and administer telecommunication networks and services”

TMN Management Architectures Functional Architecture Describes a number of management functions (control, monitor, etc.) Physical Architecture Defines how management functions are implemented into physical equipment Information Architecture Describes concepts that have been adopted from OSI management Logical Layer Architecture A model that shows how management can be structured according to different responsibilities

TMN Functional Architecture The TMN functional architecture explains the distribution of functionality within a TMN The TMN functional architecture is defined by: TMN function blocks, being the roles in which functions operate (coordinate, mediate, etc.) TMN function points, being the service boundary between two communication management function blocks

TMN Functional Architecture Interfaces between function blocks are defined as reference points q class between OSF, QAF, MF and NEF f class for attachment of a WSF x class between OSFs of two TMNs or between TMN OSF and OSF-like function in other network g class between WSF and users m class between QAF and non-TMN managed entities

TMN Functional Architecture Network Element Function, NEF: Exchanges, transmission systems, switches, etc. NEs are subject to management and support the exchange of data between users They include management functions (i.e., agents) Operation Systems Functions, OSF: Operations and Notifications Within a TMN, multiple OSFs may exist and they communicate through q3 interface OSFs belonging to different administrative domains may also communicate through x reference point CMIP CMIS

TMN Functional Architecture Work Station Function, WSF Interprets management information to a human user through g interface Q Adapter Function, QAF Non TMN entities (e.g. proprietary) can be connected to a TMN entity Translate between q reference point and m reference point (similar to a proxy agent in SNMP)

TMN Functional Architecture Mediation Function (MF) Located within the TMN Operations on the information between network elements; e.g. storage, filtering, threshold detection, etc. MF can be shared between multiple OSSs; e.g. RMON

TMN Functional Architecture Data Communication Function (DCF) Provide the necessary physical connection with various network components DCF implements layers 1-3 of OSI Connect NEs, QAs, and MDs to the OSs at the standard q interface Connect MDs to NEs and QAs using q interface

TMN Physical Architecture

TMN Information Architecture TMN makes use of OSI Systems Management principles and is based on an object-oriented paradigm. Management systems exchange information modeled in terms of managed objects (MO) A managed object (MO) is defined by: the attributes visible at its boundary the management operations which may be applied to it The behavior exhibited by it in response to management operations or in reaction to other types of stimuli (e.g., threshold crossing) The notifications emitted by it

TMN Information Architecture Information Model based on Object-Oriented Approach Manager Agent management operations M C F M C F R R application functions Q I/F R notifications TMN MIT: dynamic structure, unlike MIB which is static MCF: Message Communication Function R: Network Resource to be managed

OSI System Architecture

OSI System Architecture OSI Manager Application M-GET M SET Application Entity Presentation (ITU Recommendation X.216 and X.226) Session (ITU Recommendation X.215 and X.225) Transport (ITU Recommendation 224) Network (x.25) OSI Agent PHY Physical Medium Manage- ment Data M ACTION M-EVENT-REPORT M-CREATE M-DELETE M-CANCEL-GET DLC

OSI System Architecture Managing Process Agent CMISE CMIP lower layers Management Function

OSI System Architecture M-GET -Used to retrieve the values of one or more attributes of one or more MOs -Scoping/Filtering, Linked Replies and Synchronization -Confirmed service only M-SET -Used to replace the values of one or more attributes of one or more MOs -May be Confirmed or Unconfirmed M-ACTION -Conveys Object Class/Instance, Action Type and optional action-specific information -Meaning dependent on MO action specification -Scoping/Filtering, Linked Replies and Synchronization -May be Confirmed or Unconfirmed

OSI System Architecture M-CREATE -Permits creation of new instances of object classes -Permits specification of default values (of attributes, explicitly and/or by reference) -Permits explicit or automatic instance naming -Confirmed service only M-DELETE -Permits deletion of object class instances -Scoping/Filtering, Linked Replies and Synchronization M-CANCEL-GET -Permits a linked GET response to be terminated -Confirmed service only M-EVENT-REPORT -Conveys Object Class/Instance, Event Type and optional event-specific information -Meaning dependent on MO notification specification -May be Confirmed or Unconfirmed

OSI System Architecture Example: retrieval of all port data whose error rates exceed some threshold

OSI Communication Model Application process System-management application-service element (SMASE) SMASE services the following applications: Configuration Management Fault Management Performance Management Security Management Accounting Management A-Associate A-Release A-Abort M-EVENT-REPORT M-GET M-SET M-ACTION M-CREATE M-DELETE M-CALCEL-GET Common management information service element (CMISE) handles the communication functions of SMASE using CMIP A-Associate A-Release A-Abort RO-Invoke RO-Reject RO-Result RO-Error Association-control-service element (ACSE) Remote-operations-service element (ROSE) Setup and coordinate the activities or setting up/releasing association with the application Once association is setup, data moves from CMISE to the remote system via ROSE P-Connect P-Release P-Abort P-Data Presentation layer

OSI Communication Model A selection function to locate MO record accessed by Get/Set/Action of CMISE

OSI Information Model A managed object (MO) is defined in terms of: attributes it possesses operations that may be performed upon it notifications that it may issue its relationships with other MOs A managed-object class is a model or template for MO instances that share the same attributes, notifications, operations and behavior A MO class can be created from other MO classes (called packages) Managed Object Class Conditional Package Attributes Behavior Operations Notifications Mandatory Package A MO has the properties associated with the mandatory package and may include properties of conditional packages MO classes are obtained by using an inheritance tree Other trees are: naming tree and registration tree

OSI Information Model

Hub Managed Object Class OSI Information Model Hub Managed Object Class hub id vendor name model number serial number number of interfaces type of interfaces speed of interfaces Hub1 Instance hub id = “Hub1” vendor name = “ABC” model number =“abc” serial number = “123” number of interfaces = 12 type of interfaces = 6 speed of interfaces = 10000000 Hub2 Instance hub id = “Hub2” vendor name = “XYZ” model number =“xyz” serial number = “456” number of interfaces = 12 type of interfaces = 6 speed of interfaces = 10000000 Managed Object Class and Instances

OSI Information Model Superclass vs. subclass Switched hub Routers Regular 100-Mbps Hub Top 10-Mbps Multirate Uni-LAN Superclass vs. subclass Attributes of a Superclass are maintained by a subclass and more are possibly added Single inheritance, multiple inheritance (polymorphic), A subclass derives its property from more than one superclass and allmorphic A subclass derived from multiple superclasses takes the properties of one superclass

OSI Information Model GDMO: Guidelines for Definition of Managed Object Templates Extensions to ASN.1 to handle the syntax of managed information definition Template (similar to ASN.1 Macro) is introduced to combine definitions Mandatory package and properties MO name Specifies a superclass Templates used to combine definitions of attributes, operations and notifications Official registered name of the object class under the ISO registration tree

OSI Information Model

OSI vs. SNMP Features OSI Mgmt (CMIP) Internet Mgmt (SNMP) Information Model Object-Oriented Scalar MIB Language GDMO SNMP SMI Manager-Agent, Manager-Manager Manager-Agent, Manager-Manager Mgmt Entity Interactions Get, Set limited Create/Delete Trap M-Get, M-Set, M-Action M-Create, M-Delete M-Event-Report Protocol Operations MIT with OID Scoping/Filtering MIT with OID at leaves of the tree MO Addressing Management Five Functional Areas Not Specified Applications Standardization Body ITU-T, ISO IETF

OSI vs. SNMP OSI management uses connection-oriented transport and confirmed interactions. (reliability and bulk retrieval) They require, however, complex communication environment and result in failure-sensitivity. During network stress time, connections may not be sustainable over sufficiently long time to accomplish the management functions needed. Management entities may need to spend significant time and resources in handling lost connections. Connection-based transport may become an obstacle in accomplishing management interactions at a time when they are needed most SNMP communications use a connectionless datagram transport (UDP) with confirmed GET/SET interactions and unconfirmed event notifications (TRAPs). The responsibility to ensure reliable communications is passed to agent/manager applications. During stress time, managers may flexibly adjust their computations to handle loss A datagram model requires a simple communication environment that is easy to implement. Managers, however, can only retrieve information that fits within a single UDP frame. This limits bulk retrieval mechanisms.

Relation between TMN and OSI Reference points interconnect different function block  comparable to underlying service providers

TMN Information Architecture Manager/Agent Interworking Information Model B Information Model c system A system B system C sees MIB sees MIB M A M A CMIS CMIS CMIS CMIS CMIP CMIP Resource Resource Resource Resource OSI protocol stack OSI protocol stack * CMIP: Common Management Information Protocol * MIB: Management Information Base * CMIS: Common Management Information System

Management Service Architecture Vendor dependent

Management Service Architecture Network Element Layer, NEL Comprise NEs such as switches, routers, transmission facilities Managed by the OSFs residing in the element management layer Element Management Layer, EML It deals with vendor specific management functions and hide these functions from the layer above Functions performed: Detection of equipment errors Measuring power consumption and the temperature of equipment Measuring resource usage: CPU, shared buffer, queue length, etc. Logging of statistical data Etc.. NOTE: OSF in the element management layer and NEF may be implemented in the same piece of equipment

Management Service Architecture Network Management Layer, NML Managed functions related to interaction between multiple pieces of equipment (i.e., managing a network) Internal structure of network elements is not visible (they are vendor specific) Functions performed: Create the complete network view Setup/provisioning dedicated paths (with QoS parameters) for end users through the network Modifying routing table Monitoring link utilization Optimizing performance Fault detection The OSFs in NML interacts with the OSFs at the EML: it uses information provided by the EML to implement its functions Here OSFs in NML acts as a manager and OSFs at EML acts as an agent

Management Service Architecture Service Management Layer, SML Manage services provided by the network and “seen by users” Users may be end users (customers) and/or service providers using the telecommunication network Relies on management information provided by the Network Management Layer (NML) The internal structure of the network (i.e., network details) are hidden Functions performed: QoS management (delay, jitter, etc) Accounting/billing Addition/removal of users, etc.. Example: inter-operator management Two interconnected networks may exchange management information (e.g., necessary for QoS negotiation) but both network operators keep their network structure hidden from each other, (Proprietary).

Management Service Architecture Service Management Layer, Example A transport network (e.g., ATM, SONET or WDM) that is used by service providers to connect end routers and provide services. Border OXC Core OXC IP Border Router UNI Client/Server Model

Management Service Architecture Two independent control planes isolated from each other The IP routing, topology distribution, and signaling protocols are independent of the ones at the Optical Layer Routers are clients of optical domain The Optical Networks provides wavelength path to the electronic clients (IP routers, ATM switches) Optical topology invisible to routers Standard network interfaces are required such as UNI and NNI ? Black Box for IP networks

Management Service Architecture

Management Service Architecture Example IP over ATM example IP service provider connects to the ATM provider through X-reference points The details of the ATM backbone are hidden from the IP service provider IP provider is not allowed to monitor/modify/etc. internal equipment of the ATM backbone; rather, only high level information is communicated, such as QoS figures! An ATM link is considered as a single element for the IP network, therefore the “reference point” at the EML of IP Another “reference point” at the IP NML: Allows for fault detection, rerouting, load balancing, optimization, etc.. Finally, the IP network should monitor the ATM links for any degradation in network performance that may impact the QoS of the IP provider: Therefore another “reference point” at the service management layer

Management Service Architecture Business Management Layer, BML Includes all the functions necessary for the implementation of policies and strategies within the organization which owns and operates the services (and possibly the network) interacts with the service management layer Is influenced by high levels of control such as legislation or macro-economic factors (e.g., tariffing policies, quality maintenance strategies)

TMN vs. Internet Management TMN focuses on the specifications of management architectures whereas Internet focuses on the implementation of management protocols. Integration between TMN and SNMP is obtained through Q Adapter Function (QAF) QAF translates between q3 (OSI CMIP) reference point and m reference point (SNMP) QAF: Translating between OSI GDMO (Guidelines for the Definition of Managed Objects) and SNMP SMI is a critical task TMN (unlike Internet management) defines a separate Network to exchange management information: that is the DCN. (TMN is this sense resembles SS7 network) Internet Service management: Internet needs to be extended to allow exchange of management information between different operators..

Separating the Management from Telecommunication Networks (TN) Prevent potential problems with fault management: In case of failures, failed component may still be accessed through the separate management network OSI and SNMP have collapsed management/data network A separate management network requires additional equipment and transmission systems  costs are higher! It may also require a separate network to manage the management network (meta management) Telecommunication networks (e.g., telephony network) cannot/does not rely on asynchronous type of service provided by the data networks  a separate management network for TN is essential OSI and SNMP are aimed toward data networks: therefore, the advantages of having a separate network for management should be weighed vs. the cost incurred by adding an additional separate network