Page 438 - Handbook of Modern Telecommunications

Network Management and Administration 3-229

TCAP

SCCP ISUP SUA
IUA
MTP3 ISDN M2UA M3UA M2PA

MTP2 SCTP
MTP1 IP

T1/E1 Ethernet

FIGu RE 3.9.2 Protocol stacks for SS7 over TDM and IP/Ethernet.
traditional SS7 control traffic as well as next-generation IP-based control traffic in order to establish
(and hence monitor and troubleshoot) service sessions or transactions. Operations groups will want to
deploy sensory monitoring of SIGTRAN to identify route configuration errors, troubleshoot calls/ses-
sions, and recognize overutilized links.
3.9.2.3 New Architectures: IMS
With the introduction of purely packet-based next-generation network architectures such as IP
Multimedia Subsystem (IMS), an appropriate adaption in monitoring technology and strategy becomes
essential. IMS offers a much more flexible, adaptable, and lower cost-control layer for both wireless and
wireline services by providing access to a rich set of service enablers. Within IMS networks, a primary
purpose for sensory monitoring systems will be the need to identify and isolate problems ranging from
congestion (such as mass calling events or massive video event ) to component degradation (for example,
a failure in an enabling service application like DNS or partial equipment failure) to configuration errors
(often caused by improper traffic classification at the edge of the network) to peering problems (which
might be control traffic floods due to malfunctioning session border controllers). Malicious activities
can also create service-impacting performance issues that must be definitively resolved in order to
restore services. Decoding messages and determining the point of impact is an essential requirement
and expectation of sensory systems. Particularly important is that within IMS networks, the signaling
and control flows share the exact same topological paths as the service payloads. Consequently, the
interplay, interaction, and interrelationships between these two important but different traffic types
must be constantly monitored to ensure healthy coexistence.

3.9.3 Sensory Monitoring Technologies and Alternatives

There are many options from which to choose when considering tools and technologies for your sen-
sor network. All have advantages and disadvantages, and all vary in terms of total deployment and
operating cost. Some have specific advantages for certain types of services. Ultimately, most operators
will choose a combination of these technologies as they outfit their monitoring architecture. All of the
following categories of sensory approaches represent unique sources of sensory data, and each requires
some form of sensory system to harvest, process, analyze, and present that data.

3.9.3.1 Device-Based Sensor Networks
Historically, the vast majority of infrastructure performance monitoring has focused on gathering met-
rics and statistics from the interconnected equipment or device nodes on the network, such as switches,
routers, service nodes, firewalls, servers, etc. A wide range of protocols and data models have been used
to serve and gather this information, with some degree of standardization in management data com-
munications, such as Common Management Information Protocol (CMIP), TL1, and Simple Network