Network types What is a network? Two or more computers connected together to share data can be simply defined as a network. The connection can be established by using wired or wireless media. Numerous network types are in use, which is classified based on size and connection type. All network types have their own range. Network types There are numerous types of network systems in use. Computer networks are categorized by their size. There are four main network types, but there are more network types in use. 1. LAN 1.1. WLAN 2. MAN 3. WAN 4. PAN Those are the four main network types. But there are a few more network types in use. 5. Peer-to-Peer network 6. Cloud computing 7. Client–Server 8. CAN (Campus area network) 9. EPN (Enterprises private network) Peer-to-peer network A peer-to-peer network is essentially a straightforward network where each computer serves as both a node and a server for the files it has stored. P2P network is also known as an "equal client" system, in which instead of obtaining data from a server, "peer" machines just swap them amongst themselves. These resemble a network at home or at work. However, after installing P2P networks on the internet, more data may be shared because of the network’s scale and the number of files that are accessible. While late P2P networks like GAZA and BitTorrent were divided amongst numerous nodes to free up the bandwidth and leave the central server, earlier P2P networks like Napster used client software and a central server. Peer-to-peer networks are frequently linked to unlawful file sharing and online theft. P2P usage and network exclusivity are no longer enjoyed by anyone. P2P networks with the following include e Donkey, Gnutella, Ares Galaxy, Soulseek, BitTorrent and Utorrent. However, the common use of peer-to-peer network is sharing files on internet. Figure 1 peer-to-peer network Table 1 peer to peer network Advantages Disadvantages There is already software integrated into the P2P networks are not centralized. So, a operating system for creating the P2P single person can’t administer the whole network. network. Finding files becomes more difficult for users as a result. P2P networks are inexpensive to set up. A peer-to-peer network faces performance degradation. The network's performance will suffer when each computer is accessed by other users. There is no need for network specialists to Peer-to-peer networking offers relatively set up, handle, and maintain the network. less security for individual files. Assigning because any person with normal ICT permission is the only permission for the knowledge can handle this new work. individual files. Easy to add another node to the network. Peer-to-peer networking offers relatively less security for individual files. Assigning permission is the only security that peer-topeer networks have. The connected devices have simultaneous There is a possibility of accessing files by resource provision and consumption remote users without any permission. capabilities. It will make the network compromised. Even if there another client added to the Taking data backups in P2P networks is a network the performance will not go down. difficult task. Data is not centralized on P2P networks. Therefore, taking backups needs to be done separately on each computer, or there should be a backup system for each computer. This network is not dependent on a There is a high risk of spreading viruses on centralized server. It means even if one part P2P networks since each computer of the network fails, other parts of the connected is independent to each other. If network will work properly. one of the computers gets infected, all other computers in the network will get infected easily even there is a virus guard on them. Most often these P2P networks are used to share copyrighted contents without proper permissions. Cloud computing Cloud is a virtual space that contains resources for a targeted audience. There 4 types of cloud networks, public clouds, private clouds, hybrid clouds, and multi-clouds. In cloud computing Clients access resources through the internet from a virtual space or cloud. A public cloud is a virtual space carrying software resources and clients of that network can access those resources by connecting to that cloud through the internet. The private cloud is the important cloud type in here. These private clouds are used in companies either to get resources that are needed to the company or make private networks to the company easily. Private clouds are dedicated to a single user and all resources needed in the company environment are contained there, Employees can access that through the internet and take resources from the cloud. If a company needs to make its own network for its business it can make these networks by using cloud networks, Cloud computing networks provide network tool resources through the internet. Those clouds contain virtual firewalls, load balancers, and many other network tools. So, it’s easy to make a private network for a company using this cloud network with only an internet connection. Table 2 cloud computing Figure 2 Cloud computing Advantages Disadvantages Cost reductions – Good in-house servers and Need of a high-speed internet connection – an other network equipment are very expensive. Internet connection is required to use a cloud But clout network service providers provide a network. The speed of the internet connection very powerful network for a monthly or yearly directly affects the network. As long as the internet subscription. That is cheap than using an in- connection is out clients can’t make connections with house network. Also, when the network is not servers. needed we can remove it very easily. Powerful security systems – cloud service Keeping sensitive data in an external place – providers have thousands of important data in In cloud computing, all data is stored in the cloud their databases. So, they have specialized teams service provider’s storage. Keeping sensitive data of to keep the network secure. a company in a cloud service provider’s storage can be a security issue. Reliability - If the computer server faces a hard Less control – the company has less control over the drive failure all server-based applications will network. Cloud service provider is the controller of be unavailable soon. But cloud service the network. providers store data in multiple locations. So, one hard drive failure can’t affect the serverbased applications. Flexible to growth – Cloud computer networks use the wireless connection. So, it’s easy to expand the network than other network types. Accessibility – Cloud network users can log in to the cloud network from anywhere. It’s very flexible. Easy to implement – cloud service uses a wireless connection. So, in the implementation, no cable connections are required. So, it makes it easy to implement the network. Client-server network Client-server networks consist of a single computer that functions as a server and directs several computers. Clients of the server computer can access shared files and other resources according to the permission level of the client. Some online games like World of Warcraft, StarCraft, Overwatch are good examples for the client-server networks. client client client Server Figure 3 Client server network Table 3 client server network Advantages Disadvantages Centralizations – All essential data stored Network traffic – If a big number of clients in a single location gives good security for tried to take shared resources from the the data. user authorization and network will slow down or crash. authentication much easier and issues of the network can solve easier because of the centralization of the network Easy to manage – All client computers are High cost – implementing and maintaining connected to a server computer. The whole the cost of this network is high. For the network can be easily managed by using implementing process and for the the server. maintenance company needs network staff. Data security – centralized design of this Maintenance difficulties – Client-server network type gives extra protection because networks always required good care to all essential data is stored in the server. reduce issues in the network. If there are Also, access controls can be used to control any mistakes in the network they must the clients’ access level. solve as soon as possible. Software and hardware sharing – Client- Robustness – If the server fails the whole server networks can share software and network will fail hardware. It reduces the cost of hardware and software. Local area network (LAN) The local area network is the smallest network type after the peer-to-peer network. This network type can implement in a single location like a single building. Wireless connections and wired connections both can be used in LAN networks. The LAN networks which use Wireless connections are known as WLAN (wireless local area network). Table 4 local area network Advantages disadvantages Hardware and software can be shared – In Geographical restrictions – The biggest LAN networks hardware components and constraint of the LAN network are software are shareable. geographical restrictions. LAN network can be implemented only in a small area like a single building. High data transfer rate - LAN networks Not flexible – Because of the LAN have data transfer rate up to 1000 Mbps networks’ geographical restrictions users can’t connect anywhere they want. Easy to control – Most LAN networks use a Hard to share data via outside sources – client-server model. The limited size and the sharing data from outside sources is difficult centralization of this network make it easy and time-consuming because data to manage the network and fix errors. transportable media like pen drives can’t conveniently perform on all devices on the network. Does not cost too much – LAN networks are more inexpensive than other networks because of their small size. LAN networks do not require many powerful servers and other network hardware. Because LAN networks does not have big number of clients. Metropolitan area network (MAN) A metropolitan area network connects computers within a metropolitan area. This area can be a city or multiple cities or a given large area. MAN is in between LAN and WAN in size. MANs are created using a few LAN networks. Fibre cables are mostly used to make connections between LAN networks in the MAN network. MAN can range from 5km to 50km. The speed of the metropolitan area network is about 1000 Mbps to 100 Gbps. MAN networks have different technologies to establish the network. 1. FDDI (Fiber distribution data interface) – within 200km 2. ATM (Asynchronous transfer mode) 3. SMDS (Switched multi-megabit data service) Table 5 metropolitan area network Advantage Disadvantage Can send data to both sides simultaneously Managing difficulties – MAN networks are hard to manage because MAN networks have many clients. So, security problems, and maintenance can arise at any time. Gives security than WAN – MAN networks When connecting two LAN networks using are much more secure than WAN networks fibre cable is very important. Because because of the limited size of MAN copper cables can’t give the needed speed networks. MAN networks have less number of clients than WAN networks. So, MAN networks are much more secure than WAN networks. High speed – MAN networks can use fibre Specialized staff in networking is important connections. So, MAN networks have very – network specialized staff is needed to high data transfer speeds from 1Gbps to implement and maintain the MAN network. 100Gbps Because the MAN network is more complex than LAN network. Sharing internet – Some MAN installations More wires required - Another issue with clients are allowed to share an internet MAN is that additional cables are needed to connection. join two LANs. Campus area network (CAN) Campus area networks are spread in a limited area. This type of network is used to interconnect LANs within an educational or corporate campus. CAN network size be in between LAN and WAN networks? , Most of the CAN networks connect with the public network. CAN networks share internet access among clients and clients of the networks can access to the resources according to their permission level. Table 6 campus area network Advantages Disadvantages Accessibility of data - CAN networks Connection node bound -It doesn’t support connect several campus departments to one the maximum number of nods. Due to another. Thus, a single message is fired, and electrical overload, it is able to connect up to it readily spread to all nodes. 64 nodes. Wireless connections – In CAN networks Cable length limit – cable length in the CAN wireless connections can be used to connect network is limited to 40 metres. various departments of the organization. High network speed – high speed of this Even if CAN reduce costs by sharing internet network allows to share of big-size files over connection, hardware and software resources the network. maintenance and software development cost will be high. Sharing internet connection – in most cases CAN area networks are used to share internet connection. One ISP can share to all clients of the network. Internet expenses can reduce using this method. Wide area network (WAN) Wide area network type is the biggest network type. It doesn’t have geographical restrictions. So, it can be spread all around the world. Simply, a wide area network means a form of a telecommunication network that can connect devices from multiple locations and across the globe. internet is the best example of WAN networks. Table 7 wide area network Advantages Disadvantages Cover large geographical area – WAN Security issues – WAN networks have networks don’t have geographical restrictions different types of clients from all around the like other networks. They can be spread world. The large size of the network makes everywhere where in the world. security risks. Centralization – Head office servers are the Setup cost is high – implementing cost of a centre of the network. All essential data and WAN network is a very high cost. network controls are gathered into the head office servers. Send updated files and data - Software Troubleshooting issues – WAN is a very developers share updated files through a live large network type which spreads all around server. Hence, all programmers and office the world. WAN networks have undersea personnel instantly receive updated versions cables. So, when trouble arises in the of files. network it is hard to solve it. Sharing resources – Software and other computer resources like RAM and Hard drives can share in WANs. Helps to global business – Anyone with computer skills can spread their businesses globally. High bandwidth Network topologies The physical and logical configuration of a network's nodes and links is known as its topology. Network topologies are usually represented using graphs. Network topologies give a good idea about the placements of the nodes and the traffic flow of the network. Network administrators can decide the best places to place nodes and give the best path to traffic flow based on the network topology graph. Network topology directly affects network functionality. Choosing the right topology can improve the efficiency of the network. So, choosing the best topology is a very sensitive task in networking. well-defined network topology makes it easier for network administrators to locate faults allocate network resources and troubleshoot issues. There are network topologies in use. Topologies can be divided into two types. 1. Logical topologies The arrangement of network nodes and devices to create a logical or physical structure is known as logical topology. The arrangement of network nodes to create the network structure can be done using a variety of network topologies. Simply, logical topology explains how devices communicate and the path that use to communicate. 2. Physical topologies The connections between the devices are described by a physical topology. Physical topologies give a good idea of how devices should connect and the ideal locations for devices. This includes the physical connection of cables, switches, routers, hubs and other network hardware. i. ii. iii. iv. v. vi. Bus Topology. Ring Topology. Star Topology. Mesh Topology. Tree Topology. Hybrid Topology Bus Topology The simplest type of topology is called a bus topology, in which network communication takes place over a single bus or channel. There are numerous taps and droplines linked to the bus. Droplines are the wires that connect the bus to the computer, whereas taps are the connectors. In other words, each node is connected to a single transmission line. Table 8 bus topology Data travels to both ends in 10mbps to 100mbps speed in bus topology. The backbone is the most sensitive place in bus topology. Backbone failure will fail the whole network. RJ45 network cables or coaxial cables mostly use as the connection method of the network. Table 9 bus topology Advantages Disadvantages Ideal for small networks Backbone failure fails the entire network. Low cost Low data transfer speed Easy to install and eject devices from the Not good for large or medium size networks network One device failure does not affect to other Adding more devices will decrease network devices performances. Does not require much cabling. Because every device is receiving the identical signal from the source, there is low security. Ring topology Ring topology is the most basic network topology. Ring topology network configuration connects devices in a circular path. Each device connects with two other networks. This network type is good for a network with only a few devices. A large amount of cables is needed. packets of data travel from one device to the next until they reach their destination and it takes big time. Most ring topologies allow data packets to travel only one direction. There are many security risks in this topology. One device failure fails the entire network. Table 10 ring topology Advantages Disadvantages Because to the one-way data flow, there are High expenses fewer chances of packet collisions. More workstations can be added later in this One cable or device failure fails the entire architecture without affecting the network's network. performance. Equal access to the resources Slowed when compared to bus topology The connectivity between the nodes in the All computers must be turned on in order for topology can be managed without the use of them to connect with one another. a server. Minimum collision. Difficult to troubleshoot problems Ring topology performs better than bus It is Expensive. topology under heavy traffic since token passing is present. Ring topology performs better than bus topology under heavy traffic since token passing is present. Star topology One of the most typical network configurations is a star topology, sometimes known as a star network. With this setup, each node is connected to a hub, switch, or computer that serves as the primary network hub. In a network, the main device serves as the server, and the other devices are the clients. The number of computers that can be linked together in a star topology is technically unlimited. Yet as more computers are connected, network performance may suffer, slowing down the overall network speed. Table 11 star topology Advantages Disadvantages Network administration that is controlled if hub or switch goes down entire network from a central computer, hub, or switch. will down. Easy to add more devices to the network Extra hardware required it means extra cost will add.(switch or hub) Even one cable or device fails network Performance will predict on the switch or works properly without that failed device. hub Inserting and removing devices can be done without turning off the network Each device require only one port simple defect identification because the relationship is frequently simple to identify. Figure 4 star topology Mesh topology A network configuration known as a mesh topology has devices such as computers and routers connected to one another. Most transmissions can be spread with this architecture even if one of the connections fails. It is a topology that wireless networks frequently employ. Here is a picture of a straightforward computer configuration on a mesh network. Figure 5 mesh topology Advantages Failure of single device won’t fail the Disadvantages High cost because high amount of cables network. need to implement the network Fault identification is straightforward High risk of redundant connections Provides high privacy and security Installing mesh topology is extremely difficult. Adding new device is not an obstacle for data transmission This topology has powerful robust features. Data transmission is more consistent Tree topology Maintenance is very difficult in mesh topology.
