Data Communications
- Delivery
- Accuracy
- Timeliness
- Jitter
Components of Data Communications
- Message
- Sender
- Receiver
- Transmission Medium
- Protocol
Data Representation
- Text
- Numbers
- Image
- Audio
- Video
Data Flow
- Simplex
- Half-Duplex
- Full-Duplex
Network Models
OSI Models
- OSI Model में 7 Layer होते है, जो निम्नलिखित है
- Application Layer
- Presentation Layer
- Session Layer
- Transport Layer
- Network Layer
- Data-Link Layer
- Physical Layer
Physical Layer
the physical layer is responsible for movements of individual bits from one note to next node.
- Representation Of Bits
- Data Rate
- Physical Topology
- Transmission Mode
- Synchronization of bits
Data-Link Layer
the data-Link layer is responsible for moving forms from one note to next node
- Framing
- Physical Addressing
- Flow Control
- Error Control
- Access Control
IP Address
IP v4 ⇒ 32 bit
Total number of IP address per Network = 224
Total number of possible Address = 232
| 8 bit | 8 bit | 8 bit | 8 bit |
1 Octet =8 bit
| 1 bit | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit | |||||
| 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |||||
(1111111)2=127
Total number of Network bit =27= 128 ⇒ 128-2(MSB, LSB) =126
Sub netting
- There are 5 class
- Class A
- Class B
- Class C
- Class D
- Class E
Class A
- Total Number of Possible =231
| 8 bit | 8 bit | 8 bit | 8 bit |
| Net ID | Host ID | Host Id | Host id |
Class A Range = 1 ⇒ 126
Class B
- Total Number of Possible =
8 bit 8 bit 8 bit 8 bit Net ID Net ID Host Id Host id
Class C
- Total Number of Possible =
| 8 bit | 8 bit | 8 bit | 8 bit |
| Net ID | Net ID | Net Id | Host id |
Class D
- Total Number of Possible =
| 8 bit | 8 bit | 8 bit | 8 bit |
| Net ID | Net ID | Net Id | Host id |
Class E
- Total Number of Possible =
| 8 bit | 8 bit | 8 bit | 8 bit |
| Net ID | Host ID | Host Id | Host id |