CANOGA PERKINS 9145E NID Software Version 4.10 - Manual (Page 93)

Diagnostics 9145E NID Software User’s Manual
Network Performance
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Figure 4-38 Round Trip Availability: Canoga NID without SAM licence
Test packets are sent at the specified interval for each enabled connection. The reception of each
test packet is matched with test packets sent. Data is added to the test packet to make each
packet unique and aid in matching the returned packets with those sent. The remote node may
add data to assist in separating the data for one-way availability. The management connection
can also be used to provide insight into the one-way availability.
4.6.11 SAM Test Results
Test results are available via Telnet and CV-EMS (Reports application). Availability data is
distributed to CV-EMS(s) on an event basis (as the state changes from available to unavailable
and vice versa) and periodically (as defined by the Subscriber; for example, an interval of 15
minutes).
4.6.11.1 Operation
Testing of each connection at the Master NID requires a valid SAM license and requires that all
three levels of control (SAM, the SAM Profile and Address) be enabled. Testing of each
connection continues until any of the levels are disabled.
Test packets are sent simultaneously to each address at the interval specified in the SAM Profile.
(Test packets for each of the addresses cannot be generated in parallel. Instead, at every
interval, a burst of sequential test packets is generated by the Master NID to all the remote Slave
NIDs.) These packets contain data allowing them to be matched with the packet that is sent.
Packets are matched until the timeout period elapses. When the period has elapsed, the packet
is declared as being lost. For example, if an ongoing test has a parameter changed in its Profile,
the current Service Availability Window will complete with the old parameters and the new Profile
data will be used for subsequent Service Availability Windows.
All SAM test results are stored in the Master NID's results log and are available for display via the
Master NID's User Interface while also being distributed to CV-EMS. The frequency that the
Master NID sends SAM test results to the CV-EMS is specified as part of the SAM configuration
data.
4.6.11.2 Firmware
When firmware containing the SAM option is installed on an existing NID that is running enabled
firmware, Profiles and Addresses are updated for SAM support. SAM Profile parameters are set
to default values and the SAM state of the Profile is set to Disabled. The SAM state parameter of
the Addresses is set to Disabled. Existing PM Profile parameters are not modified. SAM
additions to Profiles and Addresses are non-intrusive to PM Profile, and Address parameters