-OSI layers: (Open System Interconnection):
1- Physical Layer:
- It is concerned with transmitting raw bits over communication channel.
- It deals with mechanical , electrical and procedural interfaces and physical transmission medium.
2- Data link layer:
1- Framing:
- Break data into frames , transmit them sequentially , process acknowledgment frames and recognize frame boundries.
2- Error handling:
- Retransmitting the frame if acknowledgment not received by receiver, aduplicate frame could be sent if acknowledgment is lost by receiver .
- It use 2 ways to handle this errors:
* CRC( cyclic redundancy code)
* Sequence numbers
3- Flow regulation:
- Keeping receiver away from drowning by a fast transmitter .
Sent from my BlackBerry® smartphone from Oman Mobile!
ليست هناك تعليقات:
إرسال تعليق