Node IDs on host/trigger/item IDs

[r-br]

Hi everyone,

I'm trying to learn the structure of Zabbix 2 with distributed nodes. Here is my nodes table:

nodeid | name                | nodetype | masterid
1      | Child Node 1        | 0        | 999
2      | Child Node 2        | 0        | 999
999    | Local Node - Master | 1        | NULL

I noticed that each item, host and trigger (and possibly other entities) have their IDs prefixed according to the nodes they belong to. Is that it, right? Here's an example:

triggerid         | status | value
  100100000010010 | 0      | 0
  200200000010016 | 0      | 0
  200200000010021 | 0      | 0
99999900000010005 | 0      | 0

My question is: why the trigger (and other) IDs are prefixed twice, with 001001 instead of just 001, and 999999 instead of just 999 ?

Thanks.