Query to compare parameter settings between databases

Create a link to the remote database then supply the name of the link as &1

set pagesize 1000
col name format a28
col local format a20
col remote format a20
select local.name, local.value local,
remote.value remote,
substr(local.isdefault, 1,1) || ‘/’ ||
from v$parameter local,
v$parameter@&1 remote
where local.name=remote.name
and lower(local.value)lower(remote.value)
order by local.name