Summary Protocol sntp , ftp, , smtp,http

UNIT 3 Data communication concepts: Types of signals encoding and decoding techniques, signal bandwidth requirements, signal formats used in LAN., switchingandbroadcasttechniques, modulation, multiplexing, switching, networkprotocols. Data communication involves the transmission of digital data over a communication channel. The types of signals used in data communication include analog and digital signals. Analog signals are continuous in nature and are used in radio and television transmission, while digital signals are discrete and are used in computers and other digital devices. Encoding and decoding techniques are used to convert digital data into a form that can be transmitted over a communication channel and then converted back to its original form at the rec eiving end. These techniques include pulse-code modulation (PCM)anddeltamodulation (DM). In a Local Area Network (LAN), digital signals are primarily used for data communication. These signals are encoded using a variety of techniques to convert digital data into a form that can be transmitted over the communication channel. The most commonencoding techniquesusedin LANs include: Pulse-Code Modulation (PCM): This is the most widely used encoding technique in LANs. It converts analog signals into digital signals by sampling the analog signal at regular intervals and converting the samples into a digital code. This method is used for both voice and data transmission. Differential Manchester Encoding: It is a method of encoding digital data on a LAN. It is commonly used in LANs that use coaxial cable, it uses a special encoding scheme that allows for a clock signal to be derived from the data signal. Manchester Encoding: This is a variation of differential Manchester encoding, it uses a special encoding scheme that allows for a clock signal to be derived from the data signal. It is commonly used in LANs that use twisted-pair cable. Decoding techniques are used to convert the encoded signal back to its original form at the receiving end. Decoding techniques are the inverse of encoding techniques. For example, the PCM decoding technique is used to convert PCM-encodedsignalsbacktotheiroriginalanalog form. The bandwidth requirement of a signal refers to the amount of frequency spectrum required to transmit the signal. Different types of data and applications have different bandwidth requirements. Ethernet, for example, uses a maximum bandwidth of 10 Mbps or 100 Mbps or 1 Gbps or 10 Gbps or 40 Gbps or 100 Gbps or 400 Gbps or 1 Tbps depending on the version used. It's also worth noting that LANs use a variety of other signal formats, such as Fiber Distributed Data Interface (FDDI) and Token Ring, depending on the network type and topology. The bandwidth requirement of a signal refers to the amount of frequency spectrum required to transmit the signal. The signal format used in LAN (LocalArea Network) is typicallyEthernet. Types of signal formats in LAN There are several types of signal formats used in Local Area Networks (LANs), including: 1. Ethernet: This is the most widely used signal format in LANs. It uses a carrier sense multiple access with collision detection (CSMA/CD) protocol for media access control, and a packet- switched method of data transmission. Ethernet uses a maximum bandwidth of 10 Mbps, 100 Mbps, 1 Gbps, 10 Gbps, 40 Gbps, 100 Gbps, 400Gbpsor1Tbpsdependingontheversionused. 2. Fiber Distributed Data Interface (FDDI): This signal format uses a token-passing method of data transmission, and provides a maximum data rate of 100 Mbps. 3. Token Ring: This signal format uses a token-passing method of data transmission and provides a maximum data rate of 16 Mbps or 100 Mbps depending on the versionused. 4. Wireless LAN (WiFi): This signal format uses radio waves to transmit data, and it has maximum data rate of 54Mbps, 150Mbps, 300Mbps, 600Mbps, 1Gbps or 2Gbps or 3Gbps or 4Gbps to 100Gbps depending on the version used. 5. Power Line Communication (PLC) this uses power lines in buildings and homes to transmit data, and it can provide maximum data rate of 14Mbps, 85Mbps, 200Mbps, 500Mbps, or 1000Mbps depending on the version used. 6. HomePNA: This signal format uses the existing phone lines in a home to transmit data, and it provides a maximum data rate of 3 Mbps. 7. Bluetooth: This signal format uses radio waves to transmit data, and it provides a maximum data rate of 1 Mbps or 2 Mbps or upto 100 Mbps depending on the version used. In a Local Area Network (LAN), the most common signal format used is Ethernet. Ethernet is a family of frame-based computer networking technologies for local area networks (LANs). It uses a carrier sense multiple access with collision detection (CSMA/CD) protocol for media access control. Ethernet uses a packet-switched method of data transmission, where data is sent in the form of packets. Each packet has its own destination address, allowing for multiple transmissions to occur simultaneously. Ethernet uses a maximum bandwidth of 10 Mbps, 100 Mbps, 1 Gbps, 10 Gbps, 40 Gbps, 100 Gbps, 400 Gbps or 1 Tbps depending on the version used. This means that the Ethernet standard defines a maximum data rate that the network can handle. As the Ethernet standard has evolved, the maximum data rate has increased, providing faster and more efficient data transfer. It's also worth noting that LANs use a variety of other signal formats, such as Fiber Distributed Data Interface (FDDI) and Token Ring, depending on the network type and topology. FDDI uses a token-passing method of data transmission and provides a maximum data rate of 100 Mbps. Token Ring uses a token-passing method of data transmission and provides a maximum data rate of 16 Mbps or 100 Mbps depending on the version used. There are also some new signal formats like Wireless LAN (WiFi) which uses radio waves to transmit data, and it has maximum data rate of 54Mbps, 150Mbps, 300Mbps, 600Mbps, 1Gbps or upto 100Gbps depending on the version used. Switching and broadcasting techniques are used to control the flow of data in a network. Switching is used to direct data from one device to another while broadcasting is used to send data to all devices on a network. Switching and Broadcast techniques Switching and broadcast techniques are methods used to control the flow of data in a network. 1. Switching: Switching is the process of directing data from one network device to another based on the destination address.There are several types of switching techniques,including circuit switching, packet switching, and message switching. Circuit switching establishes a dedicated connection between two devices for the duration of a communication session.