SQL Server's network encryption operates differently than many other database systems. Unlike LDAP which uses separate ports (389/636), SQL Server handles both encrypted and unencrypted traffic through the same default port (1433). This design choice simplifies firewall configurations but introduces interesting considerations for mixed-mode security.

The key configuration parameter is ForceEncryption in SQL Server's Network Configuration:

-- Check current encryption settings
USE master;
GO
SELECT name, value, value_in_use 
FROM sys.configurations
WHERE name LIKE '%encrypt%';
GO

There are three operational modes:

• 0 (OFF): Accepts both encrypted and unencrypted connections
• 1 (ON): Requires encryption for all connections
• 2 (STRICT): Requires encryption and validates certificates (SQL Server 2019+)

To allow both connection types while enabling SSL capability:

-- Enable encryption capability without forcing it
EXEC sp_configure 'show advanced options', 1;
RECONFIGURE;
EXEC sp_configure 'force encryption', 0;
RECONFIGURE;

Then configure the SQL Server Configuration Manager:

1. Open SQL Server Network Configuration
2. Select protocols for your instance
3. Enable both "Force Encryption" and "Certificate" tabs
4. Restart SQL Server service

For encrypted connections:

String encryptedUrl = "jdbc:sqlserver://dbserver:1433;"
    + "databaseName=AdventureWorks;"
    + "encrypt=true;"
    + "trustServerCertificate=true"; // For testing only

For standard connections:

String standardUrl = "jdbc:sqlserver://dbserver:1433;"
    + "databaseName=AdventureWorks";

SSL encryption adds approximately 10-15% overhead to network operations. In mixed mode environments:

• Monitor encrypted vs unencrypted connection ratios
• Consider implementing connection pooling differently for each type
• Use encrypted connections for sensitive operations only

When implementing mixed mode:

• Certificate errors often appear in the SQL Server error log
• Client drivers may default to encryption based on configuration
• Network sniffing tools can verify actual encryption status

-- Check active connections and their encryption status
SELECT 
    session_id, 
    connect_time, 
    net_transport,
    encrypt_option,
    auth_scheme
FROM sys.dm_exec_connections;

SQL Server handles encrypted connections differently than many other database systems. Unlike protocols like LDAP which use separate ports (389 vs 636), SQL Server employs the same default port (1433) for both encrypted and unencrypted traffic. This design choice is rooted in SQL Server's connection negotiation protocol.

The ForceEncryption parameter in SQL Server Configuration Manager determines whether the server:

• Only accepts encrypted connections (when set to TRUE)
• Allows clients to choose encryption (when set to FALSE)

-- To check current encryption settings:
USE master;
GO
SELECT name, value, value_in_use 
FROM sys.configurations
WHERE name LIKE '%encrypt%';
GO

For scenarios requiring both secure and non-secure connections:

1. Set ForceEncryption = FALSE in SQL Server Configuration Manager
2. Configure individual client connections:

   // JDBC connection string for encrypted connection
   String encryptedConn = "jdbc:sqlserver://dbserver:1433;"
       + "databaseName=AppDB;"
       + "user=appuser;"
       + "password=secret;"
       + "encrypt=true;"
       + "trustServerCertificate=true;";
   
   // JDBC connection string for non-encrypted  
   String standardConn = "jdbc:sqlserver://dbserver:1433;"
       + "databaseName=AppDB;"
       + "user=appuser;"
       + "password=secret;"
       + "encrypt=false;";

When implementing mixed mode:

• Install a valid certificate on the SQL Server (not self-signed for production)
• Configure the client trust store appropriately
• Test both connection types:

  // Test connection encryption status
  try (Connection conn = DriverManager.getConnection(connString)) {
      boolean isEncrypted = conn.unwrap(SQLServerConnection.class)
                              .getActiveConnectionProperties()
                              .getProperty("encrypt").equals("true");
      System.out.println("Encryption status: " + isEncrypted);
  }

While encryption adds overhead, modern processors handle TLS efficiently. Consider:

• Benchmark both connection types for your workload
• Encrypt sensitive operations while allowing non-encrypted for internal reporting
• Monitor using SQL Server's encryption-related performance counters