The User Datagram Protocol (UDP) is a very simple protocol in the Computer Network. Its inserts are limited to the fundamental functionality of Internet Protocol (IP). Like IP, it is an uncertain, connectionless protocol.We do not require to establish a connection with a host before exchanging data with it by using UDP. Also, there is no structure for providing information if the data which is sent is properly received or not. A unit of data transmitted by using UDP is known as a Datagram.UDP inserts four 16-bit header fields (8 bytes) to whatever data is transmitted. These fields are a ... Read More

Following are some of the services offered by the Transmission Control Protocol (TCP) to the processes at the application layer:Stream Delivery Service.Sending and Receiving Buffers.Bytes and Segments.Full Duplex ServiceConnection Oriented Service.Reliable Service.All the above mentioned TCP services are explained below in detail.Stream Delivery ServiceTCP is a stream-oriented protocol. It enables the sending process to deliver data as a stream of bytes and the receiving process to acquire data as a stream of bytes.TCP creates a working environment so that the sending and receiving procedures are connected by an imaginary "tube", as shown in the figure below:Sending and Receiving BuffersThe sending ... Read More

In this post, we will understand the difference between Time Sharing and Real-Time Operating System −Time Sharing Operating SystemIn this type of operating system, a quick response is required to be given when a request comes in.It has a switching method.Any kind of modifications can be done to the program.The resources of the computer are shared externally.It deals with multiple processes and applications simultaneously.The response to a user request is given within seconds of time.Real-Time Operating SystemIn this operating system, the computation tasks are required to be given more importance before its nominative point.It doesn’t have a switching method.No modification ... Read More

In this post, we will understand the difference between network operating system and a distributed operating system.Network Operating SystemThe main object of this system is to provide local services to remote clients.The communication takes place depending on the files.It is more scalable in comparison to Distributed Operating System.It has less fault tolerance.The rate of autonomy in a network operating system is high.It is easy to implement.The nodes of a network operating system can have different operating system.Distributed Operating SystemThe main objective of this system is to manage the resources of the hardware.The communication takes place depending on messages and shared ... Read More

DefinitionIn computer science and mathematics, a directed acyclic graph (DAG) refers to a directed graph which has no directed cycles.ExplanationIn graph theory, a graph refers to a set of vertices which are connected by lines called edges. In a directed graph or a digraph, each edge is associated with a direction from a start vertex to an end vertex. If we traverse along the direction of the edges and we find that no closed loops are formed along any path, we say that there are no directed cycles. The graph formed is a directed acyclic graph.A DAG is always topologically ... Read More

In computer networks, the shortest path algorithms aim to find the optimal paths between the network nodes so that routing cost is minimized. They are direct applications of the shortest path algorithms proposed in graph theory.ExplanationConsider that a network comprises of N vertices (nodes or network devices) that are connected by M edges (transmission lines). Each edge is associated with a weight, representing the physical distance or the transmission delay of the transmission line. The target of shortest path algorithms is to find a route between any pair of vertices along the edges, so the sum of weights of edges ... Read More

Flooding is a non-adaptive routing technique following this simple method: when a data packet arrives at a router, it is sent to all the outgoing links except the one it has arrived on.For example, let us consider the network in the figure, having six routers that are connected through transmission lines.Using flooding technique −An incoming packet to A, will be sent to B, C and D.B will send the packet to C and E.C will send the packet to B, D and F.D will send the packet to C and F.E will send the packet to F.F will send the ... Read More

DefinitionThe Dijkstra’s algorithm finds the shortest path from a particular node, called the source node to every other node in a connected graph. It produces a shortest path tree with the source node as the root. It is profoundly used in computer networks to generate optimal routes with the aim of minimizing routing costs.Dijkstra’s AlgorithmInput − A graph representing the network; and a source node, sOutput − A shortest path tree, spt[], with s as the root node.Initializations −An array of distances dist[] of size |V| (number of nodes), where dist[s] = 0 and dist[u] = ∞ (infinite), where u ... Read More

Routing Algorithms − A routing algorithm is a procedure that lays down the route or path to transfer data packets from source to the destination. There can be many paths from the source to the destination; routing algorithm mathematically computes the best path, i.e. “least – cost path”. Routing algorithms are broadly classified into adaptive and non-adaptive routing algorithms.Adaptive Routing Algorithms − Also known as dynamic routing algorithms, they makes routing decisions dynamically depending on the network conditions. It constructs the routing table depending upon the network traffic and topology.Non-Adaptive Routing Algorithms − Also known as static routing algorithms, they ... Read More

DefinitionSink trees of a given node in a computer network is a tree formed by connecting the node with all the other nodes of in the network with the optimal path, or more precisely the shortest path. Or, in other words, a sink tree is a minimal cost tree formed with the given node as the destination and all other nodes as sources. A popular measure for the path or the cost is the number of hops.ExplanationThe sink tree follows from the optimality principle. According to it, in a network of routers for data transmission, if a router ‘J’ lies ... Read More