Wi-Fi technology is a technology used for transmitting a signal using the 802.11 specifications works a lot like it does with a basic Ethernet hub: They’re both two-way forms of communication, and they both use the same frequency to both transmit and receive, often referred to a half-duplex. WLANs used radio frequencies (RFs) that are radiated into the air from an antenna that creates radio waves. These waves can be absorbed, refracted, or reflected by walls, water, and metal surfaces, resulting in low signal strength. So because of this vulnerability to surrounding environmental factors, it’s pretty apparent that wire-less will never offer us the same robustness as a wired network can, but that still doesn’t mean we’re not going to use or run the wireless or Wi-Fi.

Even though both PL/SQL and Java (or) .NET can be used, PL/SQL stands above these two in terms of integration overhead. This is because Java is an open source proprietary and Data manipulation is slightly faster in PL/SQL than in Java. 

Cloud computing architecture consists of many layers which help it to be more organized and can be managed from one place. The layers are as follows:

1. Cloud controller or CLC is the top most level in the hirerachy which is used to manage the virtualized resources like servers, network and storage with the user APIs. 

2. Walrus is used for the storage and act as a storage controller to manage the demands of the users. It maintains a scalable approach to control the virtual machine images and user data.

3. Cluster Controller or CC is used to control all the virtual machines for executions the virtual machines are stored on the nodes and manages the virtual networking between Virtual machines and external users.

4. Storage Controller or SC provides a storage area in block form that are dynamically attached by Virtual machines. 

5. Node Controller or NC is at the lowest level and provides the functionality of a hypervisor that controls the VMs activities, which includes execution, management and termination of many instances.

The security laws which are implements to secure data in the cloud are as follows:

- Input validation : controls the input data which is being to any system.

- Processing  : control that the data is being processed correctly and completely in an application.

- File : control the data being manipulated in any type of file.

- Output reconciliation : control the data that has to be reconciled from input to output.

- Backup and recovery: control the security breaches logs and the problems which has occurred while creating the back.

HTTP headers can be used in PHP by redirection which is written as:

<?header('Location: https://www.php.net')?>

The headers can be added to HTTP response in PHP using the header(). The response headers are sent before any actual response being sent. The HTTP headers have to be sent before taking the output of any data. The statement above gets included at the top of the script.

- Web servers can be infiltrated using the command shell by an attacker to read the HTML files that is getting transferred. 

- If the set-uid scripts are not proper and bad then the infiltration can happen by the attacker. 

- The processes are not given proper permissions so that the password can be changed by using the “passwd” command to change the password of the system.

- This also authenticates the user for accessing the system and the files on it containing the data. 

- The program that is used in the operating system doesn’t follow the principle of least privilege and lead to security issues.

- Files can be transferred to the server by using the FTP protocol also known as File Transfer Protocol. 

- FTP is used as a standard network protocol that transfers the file from one computer to another computer using the TCP protocol network.

- This uploads the pages and other documents that are stored in private disk to the public web hosting server. 

- FTP is used on a client server architecture that allows different controls and data connections between the client and the server. 

- FTP uses clear-text sign in protocol that allows the client to use the user name and password for authentication purpose.

drawImage(image,x,y) method is used to draw an image on the canvas.