No Topology mode supports customers who do not know their topology information (taps, amplifiers, and splitters) or how such devices are connected geographically to service locations or modems. This may mean that billing files are missing information, or cable modems do not have latitude or longitude associated with them. However, when these devices are ingested, you can generate alarms and see service locations based on a limited set of data. Under such conditions, there may be missing information in the Map and Logical views. For example, taps may not appear at all in these views, or service locations may show in Logical view but not in Map view. Cluster-based proactive and outage alarms include MTA counts.
In addition, entire fiber nodes may have no existing topology information, either because there is no topology file available to ingest, or because the ingested topology file lacks any records that pertain to certain fiber nodes. In this case, No Topology mode can create new fiber nodes and their service locations, complete with support for alarms and based entirely on billing file information.
Caveats:
- Cable modems without latitude or longitude information can be placed in a service location (SL), provided the appropriate tenant configuration is set. A cable modem may be placed in an existing service location or a new SL that other CMs can access may be created.
- Some CMs in this service location may have latitude/longitude data. The SL may choose the most common followed by the arithmetic center of available latitude/longitude data to determine its location. For fiber nodes with no topology information, if no CMs have Latitude/Longitude for a service location but the fiber node’s location was successfully calculated, the new service location will be placed a short distance away from the fiber node.
- Some service locations within a fiber node (FN) may contain latitude/longitude information, so the fiber node location will be the arithmetic center of those service locations. If only one SL has this information, the FN will be some distance away from this SL. If no SLs contain this data, the FN location will not be provided, and the FN is flagged as having insufficient position information.
- When generating a service location for unmatched cable modems in a partial topology, at least one tap must fall within the radius (from Connect Radius in the Tenant Config) of the SL's calculated coordinates. The SL will then connect directly to the nearest tap inside this radius. If the SL has no coordinates or does not have any taps within its connect radius, the SL will not be created.
- Logical view is used by default to display the FN initially rather than Map View when insufficient position information exists.
Highest Threshold Crossing
Cabling Between Points
Clustered Alarms
Clustered alarms are alarms related to points in a map with no obvious relation between them apart from their proximity to one another. The clustering algorithm searches for clusters of related issues and reports them as outage or proactive alarms. Some modems may be too far away from one another to generate alarms. Clustered Alarms will only be created for fiber nodes with completely auto-generated topologies. If a fiber node has partial or full topology provided for it, that fiber node will instead use normal outage and proactive alarms for its scans. Only service locations with latitude and longitude information are considered for alarm generation. When clustered alarm data is presented in the interface, some factors will be missing from Alarm sub-tables such as inspection points or root paths.
The strictness of including or excluding SLs in a cluster can be configured by adjusting the Clustering Scale Factor and Minimum Neighboring Cluster Points in the Billing tab of the Tenant Configuration (see the ServAssure® NXT Design and Installation Guide). Increasing the Clustering Scale Factor will increase the size of the radius (dynamically calculated for each FN based on the density of its points) in which a service location with an issue will search for additional SLs with the same issue to form a cluster. Conversely, decreasing the Clustering Scale Factor will reduce the size of this radius and create stricter regulations for how close SLs with issues must remain in order to form clusters. The Clustering Scale factor should not be reduced below 1.0.
Examples
- Normal billing and topology
files except for latitude/longitude information being removed from several
service locations
In the Topology file latitude/longitude information was removed for 5 service locations: 121, 122, 123, 128, and 129, which are attached to Tap 120. The file is ingested with no errors. Map and Logical views are created, and SC-QAM, OFDM/A, and CM tables are populated after the first scan. CMs that have no latitude/longitude information will not appear in Map View; they only appear in Logical View.
Tap 120 in Map View
Tap 120 in Logical View, displays SLs not shown in Map View
- Billing file with
latitude/longitude information but no topology information
The file is ingested with no errors, Map View and Logical View are created, and the SC-QAM, OFDM/A, and Cable Modems tables are populated after the first scan.
Billing file no topology Map view
In this view, there are no actual connections between service locations, only cables. There are no taps or other types of topology.
Billing file no topology Logical view
The lack of topology results in a flat triangle in Logical view.
No Topology Minimum Requirements
No Topology mode functionality requires only a billing file (even an incomplete one), but certain features have further minimum requirements for the billing file contents:
- A billing file with at least one record referring to a fiber node is required to use the mode and open Logical View at all.
- To create topology during the merge, the billing file record(s) must contain values corresponding to at least one of the Tenant Configuration “Service Location Top Fields” comma-separated parts.
- To display all points on Map View, at least one billing record must have latitude and longitude values. With a single billing record having these values, this will place the FN and the remainder of SLs 100m and 200m north, respectively, from the billing record with coordinates.
- To analyze a scan for clustered alarms, there must be enough billing file records with latitude and longitude values to support clustering (based on Tenant Configuration Minimum Neighboring Cluster Points). For instance, with a Minimum Neighboring Cluster Points of 4, the bare minimum number of billing records in the address file with latitude and longitude is 5. This does not guarantee that a clustered alarm can be raised (the points may be too far spread out to cluster, or not all of them may have matching proactive/outage issues during a single scan), but this is the minimum requirement to attempt the clustering process after a scan.