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Introduction to Computer Network

Nov 06, 2019

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Introduction to Computer Network. Dr. Rania R Ziedan. Agenda. Introduction Network types Network topology Network connection models OSI model. Computer network. A collection of computing devices that are connected in various ways in order to communicate and share resources or files

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Introduction to Computer Network Dr. Rania R Ziedan

Agenda • Introduction • Network types • Network topology • Network connection models • OSI model

Computer network • A collection of computing devices that are connected in various ways in order to communicate and share resources or files • Wired network: the connections between computers in a network are made using physical wires or cables • Wireless network: the connections between computers in a network are made using radio waves or infrared signals

Computer network • Each computer in the network is known as: node or host • Data transfer rate: is the speed with which data is moved from one place on a network to another, which is a key feature in computer networks

Network Types • Local Area Network (LAN): two or more computers connected together, the computers are physically near each other (for example: in the same building) • LANs are inexpensive to install • LANs provide higher speeds

Network Types • Metropolitan Area Network (MAN): usually span tens of kilometers (for example: in the same city) • The cost of installation and operation is higher. • MANs use high-speed connections such as fiber optics to achieve higher speeds

Network Types • Wide Area Network (WAN): is a connection of LANs (for example : the Internet) • WANs span a larger area than a single city. • These use long distance telecommunication networks for connection, thereby increasing the cost.

The Internet • It is a large group of computers that are connected to each other and used to send information quickly between computers around the world

Physical topology of a network • The term physical topology refers to the way in which a network is laid out physically. • The topology of a network is the geometric representation of the relationship of all the links and linking devices • There are four basic topologies possible: mesh, star, bus, and ring

Physical topology of a network • Mesh Topology • In a mesh topology, every device has a dedicated point-to-point link to every other device. • The term dedicated means that the link carries traffic only between the two devices it connects. • The number of physical links in a fully connected mesh network with n nodes  n(n-1)/2 • The mesh topology used in the connection of telephone regionaloffices in which each regional office needs to be connected to every other regional office.

Physical topology of a network • Mesh Topology • Advantages: • Each link can carry its own data load, thus eliminating the traffic problems that can occur with shared links. • A mesh topology is robust. If one link becomes unusable, it does not incapacitate the entire system. • Every message travels along a dedicated line, only the intended recipient sees it. Physical boundaries prevent other users from gaining access to messages. • Point-to-point links make fault identification and fault isolation easy. Traffic can be routed to avoid links with suspected problems. • Disadvantage: • The amount of cabling and the number of I/O ports required.

Physical topology of a network • Star Topology • Each device has a dedicated point-to-point link only to a central controller, usually called a hub. • A star topology does not allow direct traffic between devices. • The controller acts as an exchange: If one device wants to send data to another, it sends the data to the controller, which then relays the data to the other connected device. • The star topology is used in local-area networks (LANs)

Physical topology of a network • Star Topology • Advantages: • less expensive than a mesh topology, each device needs only one link and one I/O port to connect it to any number of others. • Easy to install and reconfigure. • Robustness, if one link fails, only that link is affected, all other links remain active. • As long as the hub is working, it can be used to monitor link problems and bypass defective links • Disadvantage: • the dependency of the whole topology on one single point, the hub. If the hub goes down, the whole system is dead

Physical topology of a network • Bus Topology • A bus topology is multipoint connection. • One long cable acts as a backbone to link all the devices in a network. • Nodes are connected to the bus cable by drop lines and taps. • There is a limit on the number of taps a bus can support and on the distance between those taps. As a signal travels along the backbone, some of its energy is transformed into heat. Therefore, it becomes weaker and weaker as it travels farther and farther. • Bus topology was the one of the first topologies used in the design of early local area networks. • The cable has two end terminals that dampen the signal so that it does not keep moving from one end of the network to the other.

Physical topology of a network • Bus Topology • Advantages: • Ease of installation • Bus uses less cabling than mesh or star topologies. • Disadvantages: • Difficult reconnection and fault isolation. • Difficult to add new devices. • Signal reflection at the taps can cause degradation in quality. This degradation can be controlled by limiting the number and spacing of devices connected to a given length of cable. • Adding new devices may therefore require modification or replacement of the backbone. • In addition, a fault or break in the bus cable stops all transmission, even between devices on the same side of the problem. The damaged area reflects signals back in the direction of origin, creating noise in both directions.

Physical topology of a network • Ring Topology • Each device has a dedicated point-to-point connection with only the two devices on either side of it. • A signal is passed along the ring in one direction, from device to device, until it reaches its destination. • Each device in the ring incorporates a repeater. When a device receives a signal intended for another device, its repeater regenerates the bits and passes them along

Physical topology of a network • Ring Topology • Advantages: • easy to install and reconfigure • Fault isolation is simplified. • Generally in a ring, a signal is always circulating . If one device does not receive a signal within a specified period, it can issue an alarm. The alarm alerts the network operator to the problem and its location. • To add or delete a device requires changing only two connections. The only constraints are media and traffic considerations (maximum ring length and number of devices). • Disadvantages: • Unidirectional traffic • a break in the ring can disable the entire network. • This weakness can be solved by using a dual ring or a switch capable of closing off the break.

Network connection models • Networks can also be classified according to the roles that the networked computers play in the network’s operation. • Peer-to-peer, • server-based, • and client-based.

Network connection models Peer-to-peer model all computers are considered equal. Each computer controls its own information and is capable of functioning as either a client or a server depending upon the requirement. • Peer-to-peer networks are inexpensive and easy to install. • They are popular as home networks and for use in small companies. • Most operating systems come with built-in peer-to-peer networking capability. • The maximum number of peers that can operate on a peer-to-peer network is ten. • Each peer shares resources and allows others open access to them. • Shares can be document folders, printers, peripherals, and any other resource that they control on their computers.

Network connection models Peer-to-peer network

Network connection models • client-server model is a software that consists of two parts, client systems and server systems, both communicate over a computer network

Network connection models • The client-server relationship describes the relation between the client and how it makes a service request to the server, and how the server can accept these requests, process them, and return the requested information to the client

Page request How the Web Works? • WWW use classical client / server architecture • HTTP is text-based request-response protocol HTTP HTTP Server response Server running Web Server Software (IIS, Apache, etc.) Client running a Web Browser

Client/Server • There are two types of servers: • File serverA computer that stores and manages files for multiple users on a network • Web serverA computer that responds to requests for web pages (from the browser client)

Web servers and browsers • web server: software that listens for web page requests • Apache • Microsoft Internet Information Server (IIS) (part of Windows) • web browser: fetches/displays documents from web servers • Mozilla Firefox • Microsoft Internet Explorer (IE) • Apple Safari • Google Chrome • Opera

OSI Architecture The OSI 7-layer Model OSI – Open Systems Interconnection

Description of Layers • Physical Layer • Handles the transmission of raw bits over a communication link • Data Link Layer • Collects a stream of bits into a larger aggregate called a frame • Network adaptor and device drivers in OS implement the protocol in the datalink layer • Frames are actually delivered to hosts • Network Layer • Handles routing between nodes within a packet-switched network • Unit of data exchanged between nodes in this layer is called a packet The lower three layers are implemented on all network nodes

Description of Layers • Transport Layer • Implements a process-to-process channel • Unit of data exchanges in this layer is called a message • Session Layer • Provides a name space that is used to tie together the potentially different transport streams that are part of a single application • Presentation Layer • Concerned about the format of data exchanged between peers • Application Layer • Standardize common type of exchanges The transport layer and the higher layers typically run only on end-hosts and not on the intermediate switches and routers

Summary • A computer network consists of two or more computers that are connected and are able to communicate. • The basic purpose of networks is to enable effective communication, share resources, and facilitate centralized management of data. • Networks can be classified according to their geographical boundaries or their component roles. • The topology of a network is the geometric representation of the relationship of all the links and linking devices

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Engineering Mathematics
Discrete Mathematics
Operating System
Computer Networks
Digital Logic and Design
C Programming
Data Structures
Theory of Computation
Compiler Design
Computer Org and Architecture

Basics of Computer Networking

Types of Network Topology
Transmission Modes in Computer Networks (Simplex, Half-Duplex and Full-Duplex)
Manchester Encoding in Computer Network
Difference between Broadband and Baseband Transmission
What is OSI Model? - Layers of OSI Model
TCP/IP Model
Multiple Access Protocols in Computer Network
Framing in Data Link Layer
What is Ethernet?
Ethernet Frame Format
Token Ring frame format
Difference between Byte stuffing and Bit stuffing
Hamming Code in Computer Network
Back-off Algorithm for CSMA/CD
Collision Detection in CSMA/CD
Efficiency of CSMA/CD
Efficiency Of Token Ring
Stop and Wait ARQ
Sliding Window Protocol | Set 1 (Sender Side)
What is MAC Address?
Collision Avoidance in wireless networks
Difference between Unicast, Broadcast and Multicast in Computer Network
Collision Domain and Broadcast Domain in Computer Network
Introduction of Classful IP Addressing

Computer Networking is the practice of connecting computers together to enable communication and data exchange between them. In general, Computer Network is a collection of two or more computers. It helps users to communicate more easily. In this article, we are going to discuss the basics which everyone must know before going deep into Computer Networking.

Computer Networking

How Does a Computer Network Work?

Basics building blocks of a Computer network are Nodes and Links. A Network Node can be illustrated as Equipment for Data Communication like a Modem, Router, etc., or Equipment of a Data Terminal like connecting two computers or more. Link in Computer Networks can be defined as wires or cables or free space of wireless networks.

The working of Computer Networks can be simply defined as rules or protocols which help in sending and receiving data via the links which allow Computer networks to communicate. Each device has an IP Address, that helps in identifying a device.

Basic Terminologies of Computer Networks

Network: A network is a collection of computers and devices that are connected together to enable communication and data exchange.
Nodes: Nodes are devices that are connected to a network. These can include computers, Servers, Printers, Routers, Switches , and other devices.
Protocol: A protocol is a set of rules and standards that govern how data is transmitted over a network. Examples of protocols include TCP/IP , HTTP , and FTP .
Topology: Network topology refers to the physical and logical arrangement of nodes on a network. The common network topologies include bus, star, ring, mesh, and tree.
Service Provider Networks: These types of Networks give permission to take Network Capacity and Functionality on lease from the Provider. Service Provider Networks include Wireless Communications, Data Carriers, etc.
IP Address : An IP address is a unique numerical identifier that is assigned to every device on a network. IP addresses are used to identify devices and enable communication between them.
DNS: The Domain Name System (DNS) is a protocol that is used to translate human-readable domain names (such as www.google.com) into IP addresses that computers can understand.
Firewall: A firewall is a security device that is used to monitor and control incoming and outgoing network traffic. Firewalls are used to protect networks from unauthorized access and other security threats.

Types of Enterprise Computer Networks

LAN: A Local Area Network (LAN) is a network that covers a small area, such as an office or a home. LANs are typically used to connect computers and other devices within a building or a campus.
WAN: A Wide Area Network (WAN) is a network that covers a large geographic area, such as a city, country, or even the entire world. WANs are used to connect LANs together and are typically used for long-distance communication.
Cloud Networks: Cloud Networks can be visualized with a Wide Area Network (WAN) as they can be hosted on public or private cloud service providers and cloud networks are available if there is a demand. Cloud Networks consist of Virtual Routers, Firewalls, etc.

These are just a few basic concepts of computer networking. Networking is a vast and complex field, and there are many more concepts and technologies involved in building and maintaining networks. Now we are going to discuss some more concepts on Computer Networking.

Open system: A system that is connected to the network and is ready for communication.
Closed system: A system that is not connected to the network and can’t be communicated with.

Types of Computer Network Architecture

Computer Network falls under these broad Categories:

Client-Server Architecture: Client-Server Architecture is a type of Computer Network Architecture in which Nodes can be Servers or Clients. Here, the server node can manage the Client Node Behaviour.
Peer-to-Peer Architecture: In P2P (Peer-to-Peer) Architecture , there is not any concept of a Central Server. Each device is free for working as either client or server.

Network Devices

An interconnection of multiple devices, also known as hosts, that are connected using multiple paths for the purpose of sending/receiving data or media. Computer networks can also include multiple devices/mediums which help in the communication between two different devices; these are known as Network devices and include things such as routers, switches, hubs, and bridges.

Network Topology

The Network Topology is the layout arrangement of the different devices in a network. Common examples include Bus, Star, Mesh, Ring, and Daisy chain.

OSI Model

OSI stands for Open Systems Interconnection . It is a reference model that specifies standards for communications protocols and also the functionalities of each layer. The OSI has been developed by the International Organization For Standardization and it is 7 layer architecture. Each layer of OSI has different functions and each layer has to follow different protocols. The 7 layers are as follows:

Physical Layer
Data link Layer
Network Layer
Transport Layer
Session Layer
Presentation Layer
Application Layer

A protocol is a set of rules or algorithms which define the way how two entities can communicate across the network and there exists a different protocol defined at each layer of the OSI model. A few such protocols are TCP, IP, UDP, ARP, DHCP, FTP, and so on.

Unique Identifiers of Network

Hostname: Each device in the network is associated with a unique device name known as Hostname. Type “hostname” in the command prompt(Administrator Mode) and press ‘Enter’, this displays the hostname of your machine.

IP Address (Internet Protocol address): Also known as the Logical Address, the IP Address is the network address of the system across the network. To identify each device in the world-wide-web, the Internet Assigned Numbers Authority (IANA) assigns an IPV4 (Version 4) address as a unique identifier to each device on the Internet. The length of an IPv4 address is 32 bits, hence, we have 2 32 IP addresses available. The length of an IPv6 address is 128 bits.

In Windows Type “ipconfig” in the command prompt and press ‘Enter’, this gives us the IP address of the device. For Linux, Type “ifconfig” in the terminal and press ‘Enter’ this gives us the IP address of the device.

MAC Address (Media Access Control address): Also known as physical address, the MAC Address is the unique identifier of each host and is associated with its NIC (Network Interface Card) . A MAC address is assigned to the NIC at the time of manufacturing. The length of the MAC address is: 12-nibble/ 6 bytes/ 48 bits Type “ipconfig/all” in the command prompt and press ‘Enter’, this gives us the MAC address.

Port: A port can be referred to as a logical channel through which data can be sent/received to an application. Any host may have multiple applications running, and each of these applications is identified using the port number on which they are running.

A port number is a 16-bit integer, hence, we have 2 16 ports available which are categorized as shown below:

Number of ports: 65,536 Range: 0 – 65535 Type “ netstat -a ” in the command prompt and press ‘Enter’, this lists all the ports being used.

List of Ports

Socket: The unique combination of IP address and Port number together is termed a Socket.

Other Related Concepts

DNS Server: DNS stands for Domain Name System . DNS is basically a server that translates web addresses or URLs (ex: www.google.com) into their corresponding IP addresses. We don’t have to remember all the IP addresses of each and every website. The command ‘ nslookup ’ gives you the IP address of the domain you are looking for. This also provides information on our DNS Server. \

Domain IP Address

ARP: ARP stands for Address Resolution Protocol . It is used to convert an IP address to its corresponding physical address(i.e., MAC Address). ARP is used by the Data Link Layer to identify the MAC address of the Receiver’s machine.

RARP: RARP stands for Reverse Address Resolution Protocol . As the name suggests, it provides the IP address of the device given a physical address as input. But RARP has become obsolete since the time DHCP has come into the picture.

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Illustration showing abstract representation of computing network

A computer network comprises two or more computers that are connected—either by cables (wired) or wifi (wireless)—with the purpose of transmitting, exchanging, or sharing data and resources.

You build a computer network by using hardware (for example, routers, switches, access points, and cables) and software (for example, operating systems or business applications).

Geographic location often defines a computer network. For example, a LAN (local area network) connects computers in a defined physical space, like an office building, whereas a WAN (wide area network) can connect computers across continents. The internet is the largest example of a WAN, connecting billions of computers worldwide.

You can further define a computer network by the protocols it uses to communicate, the physical arrangement of its components, how it controls traffic, and its purpose.

Computer networks enable communication for every business, entertainment, and research purpose. The internet, online search, email, audio and video sharing, online commerce, live-streaming, and social networks all exist because of computer networks.

Read how desktop as a service (DaaS) enables enterprises to achieve the same level of performance and security as deploying the applications on premises.

As networking needs evolved, so did the computer network types that serve those needs. Here are the most common and widely used computer network types:

LAN (local area network): A LAN connects computers over a relatively short distance, allowing them to share data, files, and resources. For example, a LAN may connect all the computers in an office building, school, or hospital. Typically, LANs are privately owned and managed.

WLAN (wireless local area network): A WLAN is just like a LAN but connections between devices on the network are made wirelessly.

WAN (wide area network): As the name implies, a WAN connects computers over a wide area, such as from region to region or even continent to continent. The internet is the largest WAN, connecting billions of computers worldwide. You will typically see collective or distributed ownership models for WAN management.

MAN (metropolitan area network): MANs are typically larger than LANs but smaller than WANs. Cities and government entities typically own and manage MANs.

PAN (personal area network): A PAN serves one person. For example, if you have an iPhone and a Mac, it’s likely you’ve set up a PAN that shares and syncs content—text messages, emails, photos, and more—across both devices.

SAN (storage area network): A SAN is a specialized network that provides access to block-level storage—shared network or cloud storage. To the user, it looks, and works like a storage drive that’s physically attached to a computer. (For more information on how a SAN works with block storage, see Block Storage: A Complete Guide ).

CAN (campus area network): A CAN is also known as a corporate area network. A CAN is larger than a LAN but smaller than a WAN. CANs serve sites such as colleges, universities, and business campuses.

VPN (virtual private network): A VPN is a secure, point-to-point connection between two network end points (see ‘nodes’ below). A VPN establishes an encrypted channel that keeps a user’s identity and access credentials, as well as any data transferred, inaccessible to hackers.

The following are some common terms to know when discussing computer networking:

IP address : An IP address is a unique number assigned to every device connected to a network that uses the Internet Protocol for communication. Each IP address identifies the device’s host network and the location of the device on the host network. When one device sends data to another, the data includes a ‘header’ that includes the IP address of the sending device and the IP address of the destination device.

Nodes : A node is a connection point inside a network that can receive, send, create, or store data. Each node requires you to provide some form of identification to receive access, like an IP address. A few examples of nodes include computers, printers, modems, bridges, and switches. A node is essentially any network device that can recognize, process, and transmit information to any other network node.

Routers : A router is a physical or virtual device that sends information that is contained in data packets between networks. Routers analyze data within the packets to determine the best way for the information to reach its ultimate destination. Routers forward data packets until they reach their destination node.

Switches : A switch is a device that connects other devices and manages node-to-node communication within a network, ensuring that data packets reach their ultimate destination. While a router sends information between networks, a switch sends information between nodes in a single network. When discussing computer networks, ‘switching’ refers to how data is transferred between devices in a network. The three main types of switching are as follows:

Circuit switching , which establishes a dedicated communication path between nodes in a network. This dedicated path assures the full bandwidth is available during the transmission, meaning that no other traffic can travel along that path.

Packet switching involves breaking down data into independent components that are called packets, which because of their small size, make fewer demands on the network. The packets travel through the network to their end destination.

Message switching sends a message in its entirety from the source node, traveling from switch to switch until it reaches its destination node.

Ports : A port identifies a specific connection between network devices. Each port is identified by a number. If you think of an IP address as comparable to the address of a hotel, then ports are the suites or room numbers within that hotel. Computers use port numbers to determine which application, service, or process should receive specific messages.

Network cable types : The most common network cable types are Ethernet twisted pair, coaxial, and fiber optic. The choice of cable type depends on the size of the network, the arrangement of network elements, and the physical distance between devices.

The wired or wireless connection of two or more computers for the purpose of sharing data and resources form a computer network. Today, nearly every digital device belongs to a computer network.

In an office setting, you and your colleagues may share access to a printer or to a group messaging system. The computing network that allows this is likely a LAN or local area network that permits your department to share resources.

A city government might manage a city-wide network of surveillance cameras that monitor traffic flow and incidents. This network would be part of a MAN or metropolitan area network that allows city emergency personnel to respond to traffic accidents, advise drivers of alternate travel routes. And even send traffic tickets to drivers who run red lights.

The Weather Company worked to create a peer-to-peer mesh network that allows mobile devices to communicate directly with other mobile devices without requiring wifi or cellular connectivity. The Mesh Network Alerts project allows the delivery of life-saving weather information to billions of people, even without an internet connection.

The internet is actually a network of networks that connects billions of digital devices worldwide. Standard protocols allow communication between these devices. Those protocols include the hypertext transfer protocol (the ‘http’ in front of all website addresses). Internet protocols (or IP addresses) are the unique identifying numbers that are required of every device that accesses the internet. IP addresses are comparable to your mailing address, providing unique location information so that information can be delivered correctly.

Internet Service Providers (ISPs) and Network Service Providers (NSPs) provide the infrastructure that allows the transmission of packets of data or information over the internet. Every bit of information that is sent over the internet doesn’t go to every device connected to the internet. It’s the combination of protocols and infrastructure that tells information exactly where to go.

Computer networks connect nodes like computers, routers, and switches by using cables, fiber optics, or wireless signals. These connections allow devices in a network to communicate and share information and resources.

Networks follow protocols, which define how communications are sent and received. These protocols allow devices to communicate. Each device on a network uses an Internet Protocol or IP address, a string of numbers that uniquely identifies a device and allows other devices to recognize it.

Routers are virtual or physical devices that facilitate communications between different networks. Routers analyze information to determine the best way for data to reach its ultimate destination. Switches connect devices and manage node-to-node communication inside a network, ensuring that bundles of information traveling across the network reach their ultimate destination.

Computer network architecture defines the physical and logical framework of a computer network. It outlines how computers are organized in the network and what tasks are assigned to those computers. Network architecture components include hardware, software, transmission media (wired or wireless), network topology, and communications protocols.

Main types of network architecture

There are two types of network architecture: peer-to-peer (P2P) and client/server . In P2P architecture, two or more computers are connected as “peers,” meaning that they have equal power and privileges on the network. A P2P network does not require a central server for coordination. Instead, each computer on the network acts as both a client (a computer that needs to access a service) and a server (a computer that serves the needs of the client accessing a service). Each peer makes some of its resources available to the network, sharing storage, memory, bandwidth, and processing power.

In a client/server network, a central server or group of servers manage resources and deliver services to client devices in the network. The clients in the network communicate with other clients through the server. Unlike the P2P model, clients in a client/server architecture don’t share their resources. This architecture type is sometimes called a tiered model because it's designed with multiple levels or tiers.

Network topology

Network topology refers to how the nodes and links in a network are arranged. A network node is a device that can send, receive, store, or forward data. A network link connects nodes and may be either cabled or wireless links.

Understanding topology types provides the basis for building a successful network. There are several topologies but the most common are bus, ring, star, and mesh:

A bus network topology is when every network node is directly connected to a main cable.

In a ring topology , nodes are connected in a loop, so each device has exactly two neighbors. Adjacent pairs are connected directly; nonadjacent pairs are connected indirectly through multiple nodes.

In a star network topology , all nodes are connected to a single, central hub and each node is indirectly connected through that hub.

A mesh topology is defined by overlapping connections between nodes. You can create a full mesh topology, where every node in the network is connected to every other node. You can also create partial mesh topology in which only some nodes are connected to each other and some are connected to the nodes with which they exchange the most data. Full mesh topology can be expensive and time-consuming to run, which is why it's often reserved for networks that require high redundancy. Partial mesh provides less redundancy but is more cost-effective and simpler to run.

Computer network security protects the integrity of information that is contained by a network and controls who access that information. Network security policies balance the need to provide service to users with the need to control access to information.

There are many entry points to a network. These entry points include the hardware and software that comprise the network itself as well as the devices used to access the network, like computers, smartphones, and tablets. Because of these entry points, network security requires using several defense methods. Defenses may include firewalls—devices that monitor network traffic and prevent access to parts of the network based on security rules.

Processes for authenticating users with user IDs and passwords provide another layer of security. Security includes isolating network data so that proprietary or personal information is harder to access than less critical information. Other network security measures include ensuring hardware and software updates and patches are performed regularly. This educates network users about their role in security processes, and staying aware of external threats executed by hackers and other malicious actors. Network threats constantly evolve, which makes network security a never-ending process.

The use of public cloud also requires updates to security procedures to ensure continued safety and access. A secure cloud demands a secure underlying network.

Read about the top five considerations for securing the public cloud.

As noted above, a mesh network is a topology type in which the nodes of a computer network connect to as many other nodes as possible. In this topology, nodes cooperate to efficiently route data to its destination. This topology provides greater fault tolerance because if one node fails, there are many other nodes that can transmit data. Mesh networks self-configure and self-organize, searching for the fastest, most reliable path on which to send information.

Type of mesh networks:

There are two types of mesh networks—full mesh and partial mesh.

In a full mesh topology , every network node connects to every other network node, providing the highest level of fault tolerance. However, it costs more to run. In a partial mesh topology, only some nodes connect, typically those that exchange data most frequently.
A wireless mesh network may consist of tens to hundreds of nodes. This type of network connects to users over access points spread across a large area.

Load balancers efficiently distribute tasks, workloads, and network traffic across available servers. Think of load balancers like air traffic control at an airport. The load balancer observes all traffic coming into a network and directs it toward the router or server that is best equipped to manage it. The objectives of load balancing are to avoid resource overload, optimize available resources, improve response times, and maximize throughput.

For a complete overview of load balancers, see Load Balancing: A Complete Guide .

A content delivery network (CDN) is a distributed server network that delivers temporarily stored, or cached, copies of website content to users based on the user’s geographic location. A CDN stores this content in distributed locations and serves it to users as a way to reduce the distance between your website visitors and your website server. Having cached content closer to your end users allows you to serve content faster and helps websites better reach a global audience. CDNs protect against traffic surges, reduce latency, decrease bandwidth consumption, accelerate load times. And lessen the impact of hacks and attacks by introducing a layer between the end user and your website infrastructure.

Live-streaming media, on-demand media, gaming companies, application creators, e-commerce sites—as digital consumption increases, more content owners turn to CDNs to better serve content consumers.

Avoid network traffic jams and decrease latency by keeping your data closer to your users with Akamai’s content delivery network on IBM Cloud®.

IBM Cloud® Load Balancers enable you to balance traffic among servers to improve uptime and performance.

Gain more control of your cloud infrastructure and protect your servers and network.

IBM Hybrid Cloud Mesh offers simple, secure, and predictable application-centric connectivity.

Learn how load balancing optimizes website and application performance.

An introduction to content delivery networks and how they improve customer satisfaction by optimizing website and mobile app performance.

Answers to pressing questions from IT architects on public cloud security.

IBM NS1 Connect provides fast, secure connections to users anywhere in the world with premium DNS and advanced, customizable traffic steering. NS1 Connect’s always-on, API-first architecture enables your IT teams to more efficiently monitor networks, deploy changes and conduct routine maintenance.

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INTRODUCTION TO COMPUTER NETWORKS

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