What's the difference between agentUuid and id in a bamboo agent config?

I'd like to learn more about the roles of agentUuid vs id in a bamboo agent config and why it would take two IDs to identify a bamboo agent. The only visual difference at least in the file is that the Uuid is a GUID comprised of 32 hex characters, and id is comprised of 9 decimal digits.

<!--/home/USERX/bamboo-agent-home/bamboo-agent.cfg.xml -->
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<configuration>
  <buildWorkingDirectory>/home/USERX/bamboo-agent-home/xml-data/build-dir</buildWorkingDirectory>
  <agentUuid>XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX</agentUuid>
  <agentDefinition>
    <id>XXXXXXXXX</id>
    <name>tester-agent.somecompany.com</name>
    <description>Remote agent on host tester-agent.somecompany.com</description>
  </agentDefinition>
</configuration>

Solution 1:

agentUUID is generated by remote agent to identify new agent at Bamboo side. It's used by server to identify and authorize network from agent came from. If agent authorization feature is not used, then agentUUID is not used.

agentId is id of remote agent entity at Bamboo DB table queue