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COAXIAL CABLES What is Coaxial cable? Coaxial cable is a type of transmission cable with low signal interference.  Coaxial cable consists of a center copper conductor surrounded by a plastic shield which in turn surrounded by a braided shield and all these 3 layers protected by an insulation cover. Plenum and Non-Plenum cables ·          Actually, Plenum is referred to space in a multi-story building between the ceiling of one story and floor of the next. Plenum gets its name from an HVAC term. ·          Plenum cables are Teflon cables which ensure lower emission of toxic than PVC cables when fire accidents happen in the concerned building. Coaxial plenum cables have FEP (Fluroethylenpropylene) outer cover which is commonly called as Teflon covering. ·          Non-Plenum cables are PVC cables which are not fire resistant. In fact, Non...

Different types of Computer Mouse Wireless Mouse with USB adapter    As the name indicates, a mouse without cable is called as a wireless mouse. Wireless mouse with USB adapter receiver operates through Radio frequency, i.e., Mouse has an inbuilt transmitter which sends the signals to the receiver (USB adapter) plugged in any of the USB ports in a PC or laptop. Then the USB receiver decodes the received signals and inputs to the Operating System (OS) through mouse driver software.  Wireless mouse uses a battery to get the required power.     Wired USB Mouse Today, the Wired USB type optical mouse is used by most of the people. A wired USB mouse can operate through laser or optical (LED) light or even through ball. This type of mouse dominated its predecessor wired PS/2 connector mouse.  LASER Mouse  LASER mouse can operate even on glossy surfaces, unlike an optical mouse. If you want to use the mouse on different types of...

What is bit synchronization? Determining the boundary (start and end) of signal cell is known as clock or bit synchronization. Why bit and frame synchronization techniques are used? Bit and frame synchronization techniques are used to make sure that  the signals sent from one host of the communication can be rightly decoded by the receiver. Uses of Synchronization techniques To guide the receiver in finding where data blocks start and end. To determine the time interval at which the sampling result is more accurate (with least errors). Data Transmission modes Asynchronous transmission Asynchronous transmission is a transmission in which there is no synchronization of sender and receiver clocks.  In this mode, each transmission element (character or byte) is treated independently. The receiver need to determine the boundary (starting and  ending) of each byte or character.  This mode is used whenever data has to be transfe...

NAT – Network Address Translation NAT definition: NAT is a method used to translate private IP addresses into a public IP address when the devices in the local network need to communicate through the internet. NAT allows a host that does not have a valid, registered, globally unique IP address to communicate with other hosts through the internet. Why NAT (Network Address Translation) is used? To extend the life of IPV4 as the network layer protocol of the internet by saving the IPV4 public address space. NAT saved the remaining unused IPV4 public address space by allowing the private addresses to communicate through the internet using one or few public address space. Instead of assigning 500 public IPs to the devices used in a company, one or two public address is sufficient for them to communicate through the Internet. Hosts in a LAN will use private IP addresses (free to use) to communicate with them. They use the purchased public address only when it is required to com...

Number Keyword Description Attention Required 0 Emergency System down or unusable Severe 1 Alert Immediate  action required Severe 2 Critical Critical event Important 3 Error Error event Important 4 Warning Warning event Important 5 Notification Normal (but notable) Worth to get notified, but not to worry 6 Informational Normal (only informational) To inform the admin. 7 Debug All messages as requested by user debug Debug Cisco Syslog protocol Severity levels – Points to remember ·          Syslog messages are required to know the normal events or critical events happening in a cisco switch or router. ·          Severity level’s lowest number i.e. ‘0’ resembles the high...