Transcript Management Service Architecture

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
o
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
Trunk
Test System
Telecommunication Network
Transmission
Test System
Transmission
Test System
Nodes
Voice
Voice
Public Switch
Transmission Links
Public Switch
Figure 11.1 Operations System for Network Transmission
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
Traffic
Measurement System
Traffic
Counter
Data / Telecommunication
Network
Traffic
Counter
Nodes
Router / Switch
Transmission Links
Router / Switch
Figure 11.2 Operations System for Traffic Measurement
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
f
x
g
m
class between OSF, QAF, MF and NEF
class for attachment of a WSF
class between OSFs of two TMNs or between TMN OSF and OSF-like
function in other network
class between WSF and users
class between QAF and non-TMN managed entities
TMN Functional Architecture
 Network Element Function, NEF:
o
o
o
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:
o
o
o
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
o Interprets management information to a human user
through g interface
 Q Adapter Function, QAF
o Non TMN entities (e.g. proprietary) can be
connected to a TMN entity
o Translate between q reference point and m
reference point (similar to a proxy agent in SNMP)
TMN Functional Architecture
 Mediation Function (MF)
o
o
o
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)
o Provide the necessary physical connection with
various network components
o DCF implements layers 1-3 of OSI
o Connect NEs, QAs, and MDs to the OSs at the
standard q interface
o Connect MDs to NEs and QAs using q interface
TMN Physical Architecture
Operations
System
(OS)
X
TMN
Operations
System
(OS)
X/F/Q3
Data Communications Network (DCN)
F/Q3
F
Mediation
Device
(MD)
Q3
Qx
Q3
Data Communications Network (DCN)
Qx
Q Adapter
(QA)
Network
Element
(NE)
Q Adapter
(QA)
Workstation
Qx
Network
Element
(NE)
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:
o
o
o
o
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
Agent
Manager
application
functions
M
C
F
management
operations
Q I/F
M
C
F
R
R
R
notifications
TMN
MCF: Message Communication Function
R: Network Resource to be managed
MIT: dynamic
structure,
unlike MIB
which is static
OSI System Architecture
OSI System Architecture
OSI Manager
M-CANCEL-GET
M-CREATE
M-DELETE
M-EVENT-REPORT
M-GET
Application Entity
M SET
OSI Agent
Application
M-CREATE
M-DELETE
M-CANCEL-GET
M-EVENT-REPORT
M ACTION
M SET
M-GET
OSI Manager
Application
M ACTION
Management
Data
OSI Agent
Application Entity
Presentation (ITU Recommendation
X.216 and X.226)
Session (ITU Recommendation
X.215 and X.225)
Presentation (ITU Recommendation
X.216 and X.226)
Session (ITU Recommendation
X.215 and X.225)
Transport (ITU Recommendation 224)
Transport (ITU Recommendation 224)
Network (x.25)
Network (x.25)
DLC
DLC
PHY
PHY
Physical Medium
OSI System Architecture
Management
Function
Agent
Process
Managing
Process
CMISE
lower
layers
CMIP
CMISE
lower
layers
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
-Scoping/Filtering, Linked
Replies and Synchronization
-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
-Confirmed service only
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
A-Associate
A-Release
applications:
A-Abort
Configuration Management
Fault Management
Performance Management
Security Management
Accounting Management
M-EVENT-REPORT M-GET M-SET M-ACTION
M-CREATE M-DELETE M-CALCEL-GET
Common management information service element
(CMISE)
A-Associate A-Release
A-Abort
Association-control-service
element (ACSE)
handles the
communication
RO-Invoke RO-Reject
RO-Result
RO-Error
functions of SMASE
using CMIP
Remote-operations-service
element (ROSE)
P-Connect P-Release P-Abort
Setup and coordinate the
activities or setting up/releasing
association with the application
Presentation layer
P-Data
Once association
is setup, data
moves from CMISE to the remote
system via ROSE
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
Managed Object Class
Conditional Package
Attributes
Behavior
Operations
Notifications
Mandatory Package
Attributes
Behavior
Operations
Notifications
Conditional Package
Attributes
Behavior
Operations
Notifications
 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)
 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
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
Hub2 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
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
Top
 Superclass vs. subclass
 Attributes of a Superclass are
maintained by a subclass and more are
possibly added
 Single inheritance,
 multiple inheritance (polymorphic),
o
A subclass derives its property from
more than one superclass
 and allmorphic
o
A subclass derived from multiple
superclasses takes the properties of one
superclass
Routers
hub
Switched
hub
Switched
100-Mbps
Hub
Switched
10-Mbps
Hub
Switched
Multirate
Hub
Regular
hub
10-Mbps
Regular
Hub
10-Mbps
Uni-LAN
Hub
OSI Information Model
 GDMO: Guidelines for Definition of Managed Object Templates
o
o
Extensions to ASN.1 to handle the syntax of managed information
definition
Template (similar to ASN.1 Macro) is introduced to combine
definitions
MO name
Specifies a superclass
Mandatory package and properties
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
Mgmt Entity
Interactions
Manager-Agent,
Manager-Manager
Manager-Agent,
Manager-Manager
Protocol
Operations
M-Get, M-Set, M-Action
M-Create, M-Delete
M-Event-Report
MO Addressing
MIT with OID
Scoping/Filtering
MIT with OID
at leaves of the tree
Management
Applications
Five Functional Areas
Not Specified
Standardization
Body
ITU-T, ISO
IETF
Get, Set
limited Create/Delete
Trap
OSI vs. SNMP





OSI management uses connectionoriented 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
system A
Information
Model B
MIB
sees
M
CMIS
CMIP
system C
MIB
sees
M
A
CMIS
Information
Model c
system B
A
CMIS
Resource
OSI
protocol
stack
* CMIP: Common Management Information Protocol
* CMIS: Common Management Information System
CMIS
CMIP
Resource
Resource
OSI
protocol
stack
* MIB: Management Information Base
Management Service Architecture
Vendor
dependent
Management Service Architecture
 Network Element Layer, NEL
Comprise NEs such as switches, routers, transmission facilities
o Managed by the OSFs residing in the element management layer
 Element Management Layer, EML
o It deals with vendor specific management functions and hide
these functions from the layer above
o Functions performed:
o Detection of equipment errors
o Measuring power consumption and the temperature of
equipment
o Measuring resource usage: CPU, shared buffer, queue length,
etc.
o Logging of statistical data
o Etc..
o NOTE: OSF in the element management layer and NEF may be
implemented in the same piece of equipment
o
Management Service Architecture
 Network Management Layer, NML
o Managed functions related to interaction between multiple pieces
of equipment (i.e., managing a network)
o Internal structure of network elements is not visible (they are
vendor specific)
o Functions performed:
o Create the complete network view
o Setup/provisioning dedicated paths (with QoS parameters) for
end users through the network
o Modifying routing table
o Monitoring link utilization
o Optimizing performance
o Fault detection
o The OSFs in NML interacts with the OSFs at the EML: it uses
information provided by the EML to implement its functions
o Here OSFs in NML acts as a manager and OSFs at EML acts as
an agent
Management Service Architecture
 Service Management Layer, SML
o Manage services provided by the network and “seen by users”
o Users may be end users (customers) and/or service providers using
the telecommunication network
o Relies on management information provided by the Network
Management Layer (NML)
o The internal structure of the network (i.e., network details)
are hidden
o Functions performed:
o QoS management (delay, jitter, etc)
o Accounting/billing
o Addition/removal of users, etc..
o Example: inter-operator management
o 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
o
A transport network (e.g., ATM, SONET or WDM) that
is used by service providers to connect end routers and
provide services.
IP Border Router
IP Border Router
Border OXC
Core OXC
Border OXC
UNI
Client/Server Model
Management Service Architecture
 Two independent control planes isolated from each other
o The IP routing, topology distribution, and signaling protocols are
independent of the ones at the Optical Layer
 Routers are clients of optical domain
o 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
o IP service provider connects to the ATM provider through Xreference points
o The details of the ATM backbone are hidden from the IP service
provider
o 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!
o An ATM link is considered as a single element for the IP network,
therefore the “reference point” at the EML of IP
o Another “reference point” at the IP NML:
o Allows for fault detection, rerouting, load balancing, optimization,
etc..
o Finally, the IP network should monitor the ATM links for any
degradation in network performance that may impact the QoS of the
IP provider:
o Therefore another “reference point” at the service management
layer
Management Service Architecture
 Business Management Layer, BML
o
o
o
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)
o
o
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:
o In case of failures, failed
component may still be accessed
through the separate
management network
o OSI and SNMP have collapsed
management/data network
o 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)
o 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
o 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