diff --git a/decisions/2024-02-Devices-per-atSign.md b/decisions/2024-02-Devices-per-atSign.md new file mode 100644 index 0000000..1adacac --- /dev/null +++ b/decisions/2024-02-Devices-per-atSign.md @@ -0,0 +1,48 @@ +# Devices per atSign + +* **Status:** Draft +* **Last Updated:** 2024-02-23 +* **Objective:** A standard supported maximum of devices per atSign to +engineer to. + +## Context & Problem Statement + +With each atSign it is possible to have N devices associated and connected at +any one time. With personal atSigns this is limited by the number of devices +a person may have. But in an Enterprise setting an atSign could have N devices. +With applications like SSH No Ports a company could have 10k devices all on +one atSign. + +## Goals + +Decide on a reasonable number of devices supported simulataneously on one +atSign and it associated atServer. + +### Non-goals + +We do not want to change the existing architecture and introduce complexity +to reduce the risk of an a single atSign's atServer being offline and +effecting huge numbers of devices in turn. + +## Other considerations + +Prevent a person using single atSign and connecting thousands of devices at +low cost and high risk and putting stress on the rest of the infrastructure. + +* ### Option 1 + + Keep existing atServer configuration see at what point things fail and + decide on a % of that number of devices. + +## Proposal Summary + +Soft/advertised limit of 25 concurrent active devices per atSign + +## Proposal in Detail + +The existing limit of 200 TCP sessions and the existing limits of the docker +container holding the atServer provide good support for up to 50 devices, so +the suggested maximum should be 50% of that at 25 devices per atSign. +This provides ample devices for most if not all use cases and limits risk to +a maximum of 25 devices if an atServer fails whilst also protecting from +potential abuse of over subscribed atSigns.