--- title: Network Path Terms and Concepts description: Glossary for Network Path breadcrumbs: >- Docs > Synthetic Testing and Monitoring > Network Path Testing > Network Path Terms and Concepts --- # Network Path Terms and Concepts ## Network Path{% #network-path %} Network Path provides hop-by-hop visibility into the route between a source and destination, helping you identify where latency, packet loss, or routing changes occur. ## Terminology{% #terminology %} | Concept | Description | | ------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **[Network Path](https://docs.datadoghq.com/network_monitoring/network_path.md)** | Network Path provides hop-by-hop visibility into the route between a source and a destination, so you can identify where latency, packet loss, or routing changes occur. | | **[Dynamic Tests for NetFlow](https://docs.datadoghq.com/network_monitoring/network_path/setup.md#dynamic-tests-for-netflow-experimental)** | An experimental Network Path collection method that runs Network Path tests from the Agent host to destination IPs observed in NetFlow traffic. | | **Origin** | The source that triggered a Network Path test, such as network traffic, NetFlow, a scheduled Agent configuration, or Synthetic Monitoring. Use the `origin` facet to filter paths by collection method. | | **Autonomous System (AS / ASN)** | A collection of IP routing prefixes managed by a single network operator. Network Path groups hop by Autonomous System (AS) or Autonomous System Number (ASN) to show routing domains along the path. | | **[Path View](https://docs.datadoghq.com/network_monitoring/network_path/path_view.md)** | The Network Path visualization that displays each hop, grouped by Autonomous System Number (ASN), region, or network, along with probe status and hop metrics. | | **Hop** | A network node along a route between source and destination, identified by IP address and associated metadata (ASN, cloud region, provider). | | **Source** | The starting point of a Network Path probe, such as an Agent-monitored host, container, Synthetic location, or the Agent that collects NetFlow traffic. | | **Destination** | The endpoint that the Network Path probe is targeting, such as a service, public endpoint, or domain. | | **Traceroute** | The mechanism that Network Path uses to determine intermediate hops and latency. Network Path sends controlled probes, similar to traceroute, to discover each hop on the route. | | **Latency per hop** | The round-trip time between the probe source and each hop. This helps identify slow or congested nodes. | | **Packet loss per hop** | The percentage of probe packets dropped before reaching or returning from a hop, useful for diagnosing reliability issues. | ### Path View{% #path-view %} | Concept | Description | | ------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **Aggregated hop** | A group of multiple identical hops (same IP, ASN, region), collapsed into a single representation to simplify visualization. | | **ICMP timeout or no response** | A hop where no ICMP response was received. Often appears as a gray or unknown hop in the Path View. | | **Missing hop** | A point in the path where the probe cannot identify a network node, often due to firewall filtering, ICMP rate limits, or private routing. Displayed as a dashed or empty hop. | | **Path change indicator** | A visual marker that shows when the observed route changes over time, for example an AS shift or a new hop. | | **AS grouping** | The cluster of hops belonging to the same Autonomous System, helping identify which network operator controls each segment of the path. | | **Region grouping** | The cluster of hops located within the same cloud region or geographic region. Helpful for identifying inter-regional routing. | | **Start node** | The initial node (source) where the probe begins. Represented at the far left of the Path View. | | **End node** | The destination node where the probe terminates. Represented at the far right of the Path View. | | **Hop status indicator** | The icon or color indicating whether the hop is healthy, degraded, or unreachable, based on latency and loss. | | **Probe status** | Shows whether the probe reached a hop successfully, partially, or not at all. This helps you identify where traffic stops or degrades. | | **Traversed count** | Represents the number of traceroute active probing packets received by reach hop. Higher counts suggest that the hop is consistently part of the route; lower counts may indicate path instability. | | **Traversal completion** | Represents whether or not the traceroute was able to successfully reach the destination. | | **Reachability** | The level of packet loss the destination is experiencing. | | **Latency** | How long the traceroute took to get from a source to its destination. |