## OSI Model Flashcards for StudyLib.Net
**Here are some flashcards you can use to study the OSI model on StudyLib.Net:**
**Card 1**
* **Front:** How many layers are in the OSI model?
* **Back:** 7
**Card 2**
* **Front:** What does OSI stand for?
* **Back:** Open Systems Interconnection
**Card 3**
* **Front:** What is a PDU?
* **Back:** Protocol Data Unit (data unit at each layer)
**Card 4**
* **Front:** What layer is responsible for the physical transmission of data?
* **Back:** Layer 1 - Physical Layer
**Card 5**
* **Front:** What device operates at Layer 1?
* **Back:** Repeater
**Card 6**
* **Front:** What layer defines the format of data packets?
* **Back:** Layer 2 - Data Link Layer
**Card 7**
* **Front:** What is the PDU at Layer 2 called?
* **Back:** Frame
**Card 8**
* **Front:** What layer handles logical addressing (MAC addresses)?
* **Back:** Layer 2 - Data Link Layer
**Card 9**
* **Front:** What layer is responsible for routing data packets across networks?
* **Back:** Layer 3 - Network Layer
**Card 10**
* **Front:** What is the PDU at Layer 3 called?
* **Back:** Packet
**Card 11**
* **Front:** What protocol operates at Layer 3?
* **Back:** IP (Internet Protocol)
**Card 12**
* **Front:** What layer establishes, manages, and terminates connections between applications?
* **Back:** Layer 4 - Transport Layer
**Card 13**
* **Front:** What is the PDU at Layer 4 called?
* **Back:** Segment (TCP) or Datagram (UDP)
**Card 14**
* **Front:** Which protocols operate at Layer 4?
* **Back:** TCP (Transmission Control Protocol) and UDP (User Datagram Protocol)
**Card 15**
* **Front:** What layer defines the presentation of data (encryption, compression)?
* **Back:** Layer 5 - Presentation Layer
**Card 16**
* **Front:** What layer provides services to applications like file transfer and email?
* **Back:** Layer 6 - Session Layer
**Card 17**
* **Front:** What layer interacts directly with user applications?
* **Back:** Layer 7 - Application Layer
**Card 18**
* **Front:** Which layer does HTTP operate on?
* **Back:** Layer 7 - Application Layer
**Card 19**
* **Front:** What is the benefit of using a layered model for networking?
* **Back:** Promotes modularity, interoperability, and troubleshooting
**Card 20**
* **Front:** Briefly describe the concept of encapsulation in the OSI model.
* **Back:** Data is wrapped with header information at each layer as it travels down the stack, and then unwrapped as it travels up the stack at the receiving end.