How to access an SQL server database on a different Subnet?

For example the Sql server you are trying to access is on a different subnet to the subnet of the machine you are trying to access it from. i.e. SQL Server A: 192.168.1.2 and SQL Server B: 192.168.2.2. To access SQL Server B from SQL Server A the connection string will be TCP:192.168.2.2,1433