Data transmission between hosts
1. Application Layer: User Network Interface
2. Presentation Layer: how data representation
Special encryption and decryption process
3. Session layer: different application processes remain independent
Underlying data stream
4. Transport Layer: TCP UP protocol
Split upper layer data
Establishing a connection between an end host application program
flow control
Connection-oriented service and connectionless
5. Network layer: IP protocol provides logical address of the router to make logical addressing and routing selection being used
Network functions: to provide programming that provides routing
Network layer address has two parts: a network address and host address. The network address is the whole network only.
IP Address: The network address of the host address
10. 8.2.48
Router: work in the network layer
① logical address
② choose the best path
③ Broadcast Control
④ control multicast
⑤ Traffic Management
⑥ connected to the wide area network
6. The data link layer: combined bits into bytes, byte framing
Using the MAC address access media 802.3 / 8.2.2 HDLC
Error checking, typically do not include error correction
Action: defining the physical source address and destination address of the physical
Defining network topologies
Service access point (SAP) associated with the upper-layer protocol
Frame sequence control
Flow Control
Switch / bridge: operate the data link layer
Each segment is a separate domain punch
All segments are out with a broadcast domain
Switch works:
Each segment is a separate collision domains
Broadcast packet is forwarded to all online
7. The physical layer: voltage defined transmission bit rate and the cables and pin assignment in the device
All devices are in the same collision domain
All devices in a broadcast domain through EIA / TIA-232 V.35
Devices share the same bandwidth