Chapter 10 Notes.docx - Chapter 10 Notes 10.1 Application...

Chapter 10 Notes
10.1
Application Layer
- Closest to the end user
- Network apps enable users to send and receive data
- Acts as an interface between the application and the underlying network
- Application layer protocols help exchange data between programs running
on the source and destination hosts.
- The TCP/IP application layer performs the functions of the upper three
layers of the OSI model.
- Common application layer protocols include: HTTP, FTP, TFTP, DNS
Presentation and Session Layer
The Presentation Layer
The presentation layer has three primary functions:
Formatting, or presenting, data at the source device into a compatible form for
receipt by the destination device
Compressing data in a way that can be decompressed by the destination device
Encrypting data for transmission and decrypting data upon receipt
The presentation layer formats data for the application layer, and it sets standards
for file formats. Some well-known standards for video include QuickTime and
Motion Picture Experts Group (MPEG). Some well-known graphic image formats
that are used on networks are Graphics Interchange Format (GIF), Joint
Photographic Experts Group (JPEG), and Portable Network Graphics (PNG)
format.
The Session Layer
As the name implies, functions at the session layer create and maintain dialogs
between source and destination applications. The session layer handles the