> For the complete documentation index, see [llms.txt](https://docs.eseye.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.eseye.com/api-reference/connectivity-metrics/accounting-metrics.md). # Accounting metrics Analyse network sessions and data usage. Accounting metrics describe network sessions after a device has authenticated successfully. Where authentication records tell you whether a device got onto the network, accounting records tell you what happened during the time it stayed there. > **Question answered:** How long was the device connected, and how much data did it use? ### What the records show * Session start and end times. * Session duration. * Uplink and downlink data usage. * Serving network context, where available. Uplink and downlink are reported separately, which matters for IoT estates where the traffic profile is usually asymmetric and a change in that balance is often the first sign that something on the device has changed. ### Common uses * **Per-SIM and per-fleet usage tracking:** Usage can be rolled up however your estate is organised, by device type, by customer, by region, without depending on how an operator chooses to group it. * **Internal billing and cost reconciliation:** Session-level records give you a basis for allocating cost internally and for checking it against what you are invoiced. * **Detecting abnormal session duration or usage patterns:** Sessions that run far longer than expected, or consume far more than their peers, stand out once you have the full population to compare against. * **Verifying roaming and network behaviour:** Serving network context, where available, shows which network a session actually ran on rather than which one you expected. ### Interpretation Accounting data confirms what happened during a network session. Pair it with authentication data to understand how the session started and with traffic flow data to understand where communication occurred. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://docs.eseye.com/api-reference/connectivity-metrics/accounting-metrics.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.