To compress a backup specify COMPRESSION in the WITH clause of the backup command.
Here is an example:
BACKUP DATABASE YourDatabaseName
TO DISK = 'C:\YourDatabaseName.bak'
WITH INIT, COMPRESSION
Compressing a backup typically needs less I/O, because it is smaller so it increases the speed of the backup. But compression process consumes CPU usage.
By default backup compression is off. To enable it we can use the ‘backup compression default’ configuration.
Exec sp_configure 'backup compression default', '1'
You don’t have to specify anything to restore the compressed backup