How SQL server implements cross-server queries

Dry goods are as follows:

exec sp_addlinkedserver   ' itsv ', ' ', ' SQLOLEDB ', ' crs.***.com,6598 ' exec sp_addlinkedsrvlogin  ' itsv ', ' false ', NULL, ' sa ', ' Password '--exec sp_droplinkedsrvlogin ' ITSV ', null       --Delete mappings (mapping to remote logins on linked servers)  --exec sp_ Dropserver ' ITSV '                         --delete remote server link  Select * from ITSV.biz_xjp_rpt.dbo.rpt_b_territory where repid= ' dsr0009 '

How SQL server implements cross-server queries