TEST & MEASUREMENT
By Dan Payerle Barrera, Global
Product Manager, IDEAL
Networks
www.idealnetworks.net
Applying network testing practices
to IP CCTV systems: installing,
testing and documenting
Testing and documentation of low voltage and fibre optic
communications cabling have been standard practice since
the introduction of multi-function LAN cable certifiers in the
early 1990’s. LAN cable certifiers perform a variety of tests
that ensure the installed systems meet industry standards
and generate detailed reports that serve multiple purposes.
Test reports provide assurance to the network owner
that their new network infrastructure provides the
performance for which they paid. Reports can be submitted
to the manufacturer of the cabling system to activate
warranty programs that cover material and labour defects.
Furthermore, the reports protect the installation contractor
by providing proof of ‘as-built’ performance meaning
callbacks can be billed as service calls instead of free
warranty work.
The concept of documenting CCTV installations to
provide the same level of protection to CCTV integrators
and installers is new. Until recently, test tools that allow
professional reporting of CCTV installations did not exist and
installers are routinely called back to troubleshoot problems
that may be caused by the customer’s network and not the
CCTV system.
What to test and what results mean
Virtually all new CCTV systems are digital/IP, running over
Ethernet cabling and have many advantages over analogue/
coaxial systems. One particular disadvantage of IP CCTV
is that video quality is affected by network performance.
Ideally, an IP CCTV system should be on its own network
that’s separate from an organisation’s business systems
network.
In reality, many businesses insist CCTV and business
systems run on the same network to reduce costs. As a
result, network congestion and bandwidth limitations of the
customer’s network may result in poor CCTV performance
with symptoms that include:
•
•
Reduced video frame rates: choppy video where
moving objects jump across the screen
Higher video compression: reduced image clarity, high
pixelation of video
•
Network buffering: video pauses and hesitates, then
catches up and hesitates again in a continuously
repeating cycle
When any of the above symptoms occur, the client will
assume the fault is with the CCTV system, putting the
integrator in a position of troubleshooting the client’s
network or trying to prove that the CCTV system is being
affected by external conditions.
Documenting the CCTV system before turning it over to
the client gives integrators/installers proof of performance
that the cameras are performing as expected after
installation. The equipment used to test and document a
CCTV system is different from cable certifiers. Instead of
measuring the characteristics of the cabling, a CCTV test
tool is going to capture network and video information to
provide a snapshot of each camera’s configuration.
Data to used to generate CCTV test reports:
•
Camera IP address: the network address of the camera
and whether it is fixed (static) or assigned by the
network (dynamic). The IP address is programmed
during installation
www.networkseuropemagazine.com
29