The physical address is added
No, frame delimiting is a primary responsibility of the Logical Link Control sublayer of the Data Link Layer.. Data link layer exists of 2 sublayers; Media Acces control Sublayer (MAC) & Logical Link Control sublayer (LLC)
Frame relay and PPP is used with WAN encapsulation. Frame Relay most closely compares to the OSI data link layer (Layer 2). If you remember that the word "frame" describes the data link layer protocol data unit (PDU), it will be easy to remember that Frame Relay relates to OSI Layer 2. Like other data-link protocols, Frame Relay can be used to deliver packets (Layer 3 PDUs) between routers.
Primary functions provided by Layer 2 data encapsulation include data link layer addressing, and the detection of errors via cyclic redundancy check calculations. An additional function is delimiting groups of bits into frames.
* addressing * error detection * frame delimiting
HDLC
the network layer --> check your question. ^^^^^^^^^^^^^^^^^^^^^^^^^^^ That is totally not the right answer, how about you actually read the book for the course. It is the data link layer that does encapsulation. I agree - its the Data Link Layer which encapsulates the Network layer...NOT the Network Layer.
Encapsulation in layered communications refers to the process of wrapping data with protocol information as it moves down the layers of the OSI or TCP/IP model. Each layer adds its own header (and sometimes trailer) to the data from the layer above, creating a "packet" at the transport layer, a "frame" at the data link layer, and so on. This method allows each layer to operate independently while ensuring that the necessary information is available for proper data transmission and reception. Ultimately, encapsulation facilitates modular communication by allowing different networking protocols to work together seamlessly.
The trailer protocol is a link-layer encapsulation method that rearranges the data contents of packets sent on the physical network. by : Umesh The trailer indicates where a frame ends. It, along with the header, encapsulates a packet, making it a frame. by: eSeriate
Layer 2 (Data Link Layer) http://compnetworking.about.com/cs/internetworking/g/bldef_bridge.htm
Encapsulation is the process of adding header information to the layers' data "payload". As the "payload" is passed from one TCP/IP (or OSI) layer to the next, encapsulating layer information is wrapped around the data. So, for example, if the application layer produces a data payload for transmission, it encapsulates it with application-layers headers, which then gets passed to the presentation layer. The presentation layer does the same and so down the protocol stack before transmission across the physical media. At the destination, the process is reversed by way of de-encapsulation where the headers are stripped-off by each matching layer at the destination. 1. Application, Presentation and Session layers create data. {Encapsulation headers added by layers} 2. Transport layer coverts data into segments for transport across the network. {Encapsulation headers added by layer} 3. Network layer converts segments into packets (or Datagrams). {Encapsulation headers added by layer} 4. Data Link layer converts packets (and datagrams) into Frames and the Data Link header is added. {Encapsulation headers added by layer} 5. Physical - frames are converted into bits for transmission over the physical media.{Encapsulation headers added by layer}
In the OSI model, encapsulation occurs as data is passed down through the layers. At the Application layer (Layer 7), data is created and then passed to the Presentation layer (Layer 6) for formatting. The Session layer (Layer 5) manages sessions, while the Transport layer (Layer 4) adds headers for segmentation and reliability. As data moves down to the Network layer (Layer 3), it receives IP addressing, followed by the Data Link layer (Layer 2), which adds MAC addressing and framing, and finally, the Physical layer (Layer 1) transmits the raw bits over the physical medium. Each layer adds its own header (and sometimes footer) to the data, forming a protocol data unit (PDU) specific to that layer.