1. BTEC National Level 3 Website Production

2. Lesson objectives To understand factors that influence website performance To understand factors that influence website performance To understand the risks to the security of a website To understand the risks to the security of a website

3. Starter Aptimize Aptimize Improves website performance Improves website performance Think about the things that are downloaded when you visit the page Think about the things that are downloaded when you visit the page http://www.youtube.com/watch?v=J Twges72rdg http://www.youtube.com/watch?v=J Twges72rdg http://www.youtube.com/watch?v=J Twges72rdg http://www.youtube.com/watch?v=J Twges72rdg

4. Compression We discussed compression is used in images, such as bitmap (resolution dependent) and vector We discussed compression is used in images, such as bitmap (resolution dependent) and vector Compress images = lose quality Compress images = lose quality We compress images because it will reduce the file size We compress images because it will reduce the file size Reduce file size = smaller page = faster download especially for those on dial-up Reduce file size = smaller page = faster download especially for those on dial-up

5. Example GIF: 64KBJPEG: 24KB

6. Activity images and video(15) Activity: look at an existing website. Open the code for that website: view >> page source. What image file types have been used and why? Activity: look at an existing website. Open the code for that website: view >> page source. What image file types have been used and why? Find examples of different software you can use to compress images Find examples of different software you can use to compress images 1. download an image 1. download an image 2. Use: imageoptimizer.net, shrinkpictures.com or jpeg-optimizer.com to check what the image will look like when compressed 2. Use: imageoptimizer.net, shrinkpictures.com or jpeg-optimizer.com to check what the image will look like when compressed

7. Activity sound and video (12) Apart from images we can also compress sound files: Apart from images we can also compress sound files: WAV = uncompressed WAV = uncompressed MP3 = compressed format MP3 = compressed format Videos can slow down a website, a possible solution is streaming. Explain how… Videos can slow down a website, a possible solution is streaming. Explain how…

8. Server side factor (12) If a website is slow to download what do you think will happen to the visitors If a website is slow to download what do you think will happen to the visitors Bandwidth: determines how much traffic can be handled by the server, at any one time Bandwidth: determines how much traffic can be handled by the server, at any one time Find out how the performance of a server can affect the users Find out how the performance of a server can affect the users Look at bandwidth, server memory, processing and storage Look at bandwidth, server memory, processing and storage Find out the Internet connection speed Find out the Internet connection speed

9. 2.3 Security There are many risks to the security of a website There are many risks to the security of a website An example of this is hackers who attempt to access a computer system to steal data, change it or destroy it An example of this is hackers who attempt to access a computer system to steal data, change it or destroy it Viruses and general malware cause damage Viruses and general malware cause damage http://www.youtube.com/watch?v=IUVPxc aEA8w http://www.youtube.com/watch?v=IUVPxc aEA8w http://www.youtube.com/watch?v=IUVPxc aEA8w http://www.youtube.com/watch?v=IUVPxc aEA8w

10. Security protection mechanisms Firewall Firewall SSL SSL Adhere to standards Adhere to standards

11. Activity: security Research the threats to websites including hackers and viruses. Make notes for future reference in your coursework Research the threats to websites including hackers and viruses. Make notes for future reference in your coursework Research the methods to protect websites including firewalls. Research the methods to protect websites including firewalls.

12. Server side factor (12) If a website is slow to download what do you think will happen to the visitors If a website is slow to download what do you think will happen to the visitors Bandwidth: determines how much traffic can be handled by the server, at any one time Bandwidth: determines how much traffic can be handled by the server, at any one time Find out how the performance of a server can affect the users Find out how the performance of a server can affect the users Look at bandwidth, server memory, processing and storage Look at bandwidth, server memory, processing and storage

13. Rest of the lesson Work on P1 criteria challenge 1 Work on P1 criteria challenge 1 Work on P2 criteria challenge 2 Work on P2 criteria challenge 2