Understanding the OSI Seven Layer Networking product
- March 14, 2017
- Posted by: marlenedubois
- Category: Home Health Aide Training
A computer network is usually made up of many parts as well as also the longest-used method to conceptualize computer networks is usually known as the Open Systems Interconnection (OSI) Seven Layer product. For Network Technicians the OSI Seven Layer product provides a practical tool for diagnosing network problems as well as a common language for describing networks.
Layer 1 – Physical: Includes the cable used to move bits of data between computer systems. Unshielded Twisted Pair (UTP) that has a CAT 5E or CAT6 rating is usually common in most networks. Fiber Optic cable which uses light waves as to transmit data packets as opposed to electrical waves has significant speed as well as also distance advantages over UTP, however lacks the durability. Hubs, which operate much like old-time telephone switchboards moving data to connected systems are also included in Layer 1 of the OSI product, as well as radio waves transmitted through the air to a Wireless Access Point (WAP).
Layer 2: Data Link: Includes the Network Interface Card (NIC), which serves as the interface between the computer as well as also the network. The NIC is usually usually built into the motherboard as well as also is usually assigned a Media Access Control (MAC) address in which gives each system connected to a network a unique ID. The MAC address is usually used to ensure in which data is usually delivered to the right computer, as well as also NICs use electricity to send as well as also receive packets of binary data as pulses of electricity, light, or radio waves.
Layer 3: Network: Includes software designed to use logical addressing called protocol in which is usually used to efficiently move data packets along the physical as well as also data link layers of the OSI product. The most common protocol is usually TCP/IP which works in tandem with Routers at layer 3 to ensure in which data is usually sent as well as also received at the desired computer systems. various other protocols in which use logical addressing such as POP as well as also SMTP for email also reside at the network layer.
Layer 4: Transport: Includes protocol in which is usually specifically designed for assembly as well as also disassembly of data packets. Data must be sent in chunks in which will fit into specific packet sizes, which is usually then reassembled into readable data by the receiving computer system. The transport layer network protocol breaks up the data as well as also assigns sequence numbers which allows receiving systems to process the data.
Layer 5: Session: Includes protocol in which initiates data transfer sessions between computer systems, accepts incoming sessions, as well as also opens as well as also closes existing sessions. The session layer’s network protocol also keeps track of computer naming conventions to facilitate data transfer sessions between computer systems.
Layer 6: Presentation: Includes software in which converts data into standardized file formats which allow computers to receive data as well as also convert the item into a format in which is usually readable by the computer systems. PDF as well as also Adobe Acrobat are an example of standardized file format software in which allow computer systems to convert data into readable files.
Layer 7: Application: Includes software applications in which allow users to access as well as also utilize data files. Web browsers such as Internet Explorer as well as also Mozilla Firefox, as well a email programs like Outlook Express are found at the Application layer. Layer 7 also includes code built into operating systems in which enable network-aware applications as well as also Application Programming Interfaces (APIs).
Please Do Not Throw Sweet Potato Away: A useful mnemonic for memorizing the seven layers of the OSI Seven Layer Networking product.