Technology
Introduction
A network switch is a small hardware device that is used to connect two or multiple computers within a local area network (LAN). This enables the paring of the computers hence sharing of information is facilitated. The networking switches normally operate at a layer two that is data link layer of the Open Systems Interconnection model (OSI). Network hubs are very similar to network switches but after close scrutiny, a network switch can inspect data packages received, can determine the final destination while sourcing the original source of the data. They deliver the message to the devices connected to the network hence preserving network bandwidth providing better performance as compared to a hub.
Synchronous and asynchronous
Asynchronous communication normally uses a transmitter, a receiver and a wire without coordinating the timing of the particular bits. Synchronous communication defines the communication parameters particularly in the data link section before commencing communication
Analog and digital
A digital switch is used to link up signals that are usually in a 1or 0 natures that is, they should be in a digital nature. An analog switch is used to link signals such as audio or a voltage that has an infinite number. The main difference between the two is that a digital switch does not have the capability to go through changing signals that occur in infinite number of states.
Parallel and serial transmission
Serial and parallel transmissions are very similar in that the messages in terms of bytes are sent along a medium after another. They also have differences.one of the difference between the two is that in a serial type of transmission, the bits that constitute to each byte are usually sent along a specific path one after another while in a parallel type of transmission, parallel paths are used by each bit of a byte to ensure that they arrive to the destination simultaneously. For this reason, parallel transmission is faster than a serial transmission. Due to the extreme wiring in a parallel transmission set up so as to create an extra path, it tends to be more expensive than a serial transmission set up.
Duplex vs. Simplex
Most serial connections are of simplex connection in nature. Simplex connections are laid out in such a way that the transmitter sends a task to the receiving device which determines what was sent and to perform the task correctly. For example, a mainframe computer may send a signal to a printer instructing it to print a document. It does this without checking the printer’s availability but expects the task to be done. In contrast, a duplex connection is a two way communication that is, the external links has the ability to communicate in both ways. For example, fiber optic, satellite link and two way radios.
Xon and Xoff
XON/XOFF is defined as a communication protocol that is used to ensure data flow between the computer and other external devices is correct. The initial “X” resembles a transmitter. A computer will normally send an XOFF character signal when data processing has exceeded its limit and when it resumes taking in more data; it sends the XON signal to the transmitter.
Baseband and broad band
For starters a broadband sends its information using an analog signal while a baseband sends digital signals. A baseband communication is bi-directional that is, the same channel of data is used to send and receive signals while in broadband communication, it is unidirectional that is, two paths are needed to facilitate sending and receiving of data.
Conclusion
Creating a network switches has been very important in the information world. Without them relaying of information would be next to impossible or time taken would have been a lot. Therefore, switches are the link and the bridge that joins two destinations that may be miles or worlds apart. Whether locally or globally, switches are very important.
Reference
Guide to Networking Essentials fifth edition
http://www.inetdaemon.com/tutorials/basic_concepts/communication/duplex_vs_simplex.shtml
http://www.blurtit.com/q251563.html
http://www.omnisecu.com/basic-networking/difference-between-baseband-and-broadband.htm
