> For the complete documentation index, see [llms.txt](https://docs.console.zenlayer.com/welcome/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.console.zenlayer.com/welcome/glossary/h-n/l.md).

# L

## Latency

The time delay between the sending and receiving of data over a network. Latency is typically measured in milliseconds (ms) and can affect the performance of real-time applications, such as online gaming and video conferencing.

## LOA

A Letter of Authorization (LOA) is a formal document in which the holder of an Internet resource, such as an IP address block or Autonomous System (AS) number, authorizes another party — typically an upstream provider or data center operator — to announce, route, or otherwise use that resource on their behalf. LOAs are commonly required when bringing your own IP space (BYOIP) to a new provider or when requesting route announcements and cross-connects.