Arman Hasen, Author at Networkwalks Academy

Bit Error Rate & BERT Meter (part1)

Performance of the transmission system is of crucial importance to communication quality of the whole communication network. Good performance can be achieved through proper control over Bit Error Rate & BERT. The major factors affecting the performance of SDH transmission network includes bit error, jitter and wander. So, what are the Bit Errors? Why are they so important to control? Do the Bit errors affect my network performance? These are some of the questions that every network engineer and optical transmission engineer must know. Let’s dissect these questions & their answers one by one. “Bit Error is the amount of Read More …

IP Address & its Types

“IP address is a unique number which is used to identify network devices in computer networks”. An IP address mainly serves two functions: host or network interface identification and location addressing. It is a logical numeric address that is assigned to every single computer, printer, switch, router or any other device that is part of a TCP/IP based network. The IP exists in every network, even only a pair of computers or a network of a large enterprise. Each computer, without exceptions, has its own unique address, if there is a connection to the network. Each of the computers in Read More …

Cloud Computing

Cloud Computing is an approach to offer IT Services to customers remotely. It is the practice of using IT Network which are physically hosted in a remote location (mostly on the Internet) to store, manage and process data, rather than a local server or a personal computer. It is the delivery of hosted services over the internet. Simply, it is the technology of distributed data processing in which some scalable information resources and capacities are provided as a service to multiple external customers through Internet technology. Cloud computing is generally referred to the delivery of computing services over the Internet. Read More …

TCP 3-way Handshake Process

TCP (Transmission Control Protocol) is a connection oriented protocol which works on Transport Layer for reliable communication between network devices. TCPv4 was published in RFC-793 in 1981 and is still the current version. TCP is a connection-oriented full-featured transport layer protocol that provides all the functions needed by a typical application for the reliable transportation of data across an internetwork. TCP is a host-to-host protocol. TCP provides reliable communication with a mechanism called Positive Acknowledgement with Re-transmission (PAR) employing the 3-way Handshake. 3-way Handshake Process TCP uses a process called 3-way Handshake for reliable communication. In 3-way Handshake process, three Read More …

Application Layer of OSI Model (Layer-7)

Application Layer is the highest layer in seven layer OSI Model. It is responsible for End user Network Applications Management. This is the layer where real traffic data is generated in most of the cases. For example, this could be a web request generated from HTTP protocol or a command from telnet protocol. OSI Model divides the network communication processes into seven layers in order to simplify it. Each layer performs specific functions to support the layers above it. The seven Layer model starts from Physical Layer & goes till Application Layer on the top, as below in figure: Functions/Duties Read More …

Presentation Layer of OSI Model (Layer-6)

Presentation Layer is responsible for representation & formatting of data for session Layer in encapsulation process. It is the 6th Layer in the seven layer OSI Model after Session Layer. Presentation layer serves like a translator & takes care that the data is sent in such a way that the receiver will understand the information or data and will be able to use the data. OSI Model divides the network communication processes into seven layers in order to simplify it. Each layer performs specific functions to support the layers above it. This seven Layer model starts from Physical till Application Read More …

Session Layer of OSI Model (Layer-5)

Session layer of OSI Model is designed to allow devices to establish and manage sessions so that multiple channels could be established between same terminals and hosts. Session Layer is the fifth layer in the 7-Layer OSI Model after Transport Layer. Session Layer is also called as ‘Port Layer’. The main function of Session Layer is to establish, maintain and synchronize the interaction between communicating systems and hosts like computers and servers. It allows information of different streams, originating from different sources, to be properly combined or synchronized. OSI Model divides the network communication processes into seven layers in order Read More …

Transport Layer of OSI Model (Layer-4)

Transport Layer is the fourth layer in 7 Layer OSI Model after Network Layer. Similar to Layer-2 and Layer-3, this layer also performs addressing & multiplexing but in different domain through TCP and UDP. OSI Model divides the network communication processes into seven layers in order to simplify it. Each layer performs specific functions to support the layers above it. The seven Layer model starts from Physical till Application Layer & Transport layer is in the middle. The core concept behind Transport layer is the “support of Multitasking”. It allows same computer, browser & internet connection to work on multiple Read More …

Network Layer of OSI Model (Layer-3)

Network Layer is the 3rd layer in 7-Layer OSI Model after Data Link Layer. This is the place where most Routing and network stuff resides. It controls the Logical boundaries of Network. Network Layer controls the operation in networking at routing layer. The main aim of this layer is to deliver packets from source to destination across multiple links or networks. If two computers or host systems are connected on the same link, then there is no need for a network layer. Each layer in OSI Model performs specific functions to support the layers above it. This 7x Layer model Read More …

Data Link Layer of OSI Model (Layer-2)

Data Link Layer of OSI Model is the second layer in seven layer model. Data Link layer performs two very important functions of physical addressing and switching. Data link layer is the place where most LAN, Ethernet and wireless LAN technologies are defined. Each layer in OSI Model has its own duties & specific functions to perform so that it can support the layers above it. Below figure shows the position of Data Link layer in the OSI Model: Data link layer controls the Layer-2 Network boundary. It provides functional and procedural methods of transferring data between two points. It Read More …