Today, the concept of network connections will not surprise anyone. However, when we mention them, many of us don’t even think much about what such a connection is and how network services work. Let’s try to consider this issue in a brief summary, since a whole monograph could be written about networks and their capabilities in the modern world.
Network Architecture: Basic Types
So, as follows from the basic interpretation of the term itself, computer networks are a certain number of terminals (computers, laptops, mobile devices) connected to each other, which, in fact, forms a network.
To date, there are two main types of connections: wired and wireless, using a connection through a router such as a Wi-Fi router. But this is only the tip of the iceberg. In fact, the network architecture involves the use of several components, and therefore may have a different classification. It is generally accepted that at the moment there are three types of networks:
- peer-to-peer networks;
- Networks with dedicated servers
- hybrid networks, including all types of nodes.
In addition, broadcasting, global, local, municipal, private networks and other varieties make up a separate category. Let us dwell on the basic concepts.
Description of networks by type
Let's start with the networks based on the interaction "main computer in the network-client." As already clear, the central terminal occupies the leading position here, on which the network and all its components are managed. Client terminals can only send requests for a connection and in the future for information. The main terminal in such a network cannot play the role of a client machine.
Peer -to- peer networks, often called peer-to- peer networks, differ from the first type in that the resources in them are equally distributed between all connected terminals. The simplest example is the process of downloading files using torrents. The final file in full or partially downloaded form can be located on different terminals. The user system that downloads it to his computer uses all the resources currently available on the network to download parts of the desired file. The more of them, the higher the download speed. At the same time, network addressing does not play a special role. The main condition is that the appropriate software is installed on the client machine. It will produce client requests.
The client-server network architecture is the simplest. For simplified understanding, the connection between computer terminals (it does not matter how it is made) can be represented in the form of a library hall, in which there is a storage or shelves with books (central server) and desks where visitors can read material taken from shelves.
Obviously, there is a clear relationship: the visitor comes to the library, registers or submits already registered personal data (network identification based on the assigned IP address), then searches for the necessary literature (network request), finally takes the book and reads it.
Naturally, the comparison is the most primitive, because modern networks are much more complicated. Nevertheless, for a simplified understanding of the structure of such an example is perfect.
Terminal Identification Issues
Now a few words about how recognition of network computers of any type is made. If anyone does not know, when connecting to any terminal, two types of IP addresses are assigned, or, more simply, a unique identifier: internal and external. The internal address is not unique. But the external IP - yes. There are no two machines with the same IP in the world. This is what allows you to identify any gadget, whether it is a computer terminal or a mobile device, one hundred percent.
The corresponding protocol is responsible for all this. At the moment, the most common and most widely used is IPv4. However, as practice shows, he has already outlived himself, as he has become unable to provide unique addresses due to the increased number of client devices. Look only at mobile equipment, because over the past decade, there have been so many used gadgets that almost every second inhabitant of the Earth has at his disposal the same mobile phone.
IPv6 Protocol
Thus, the architecture of the network, in particular the Internet, began to change. And the fourth version was replaced by the sixth (IPv6). While it has not yet received widespread application, nevertheless, it is alleged that the future is not far off, and soon almost all providers that provide communication services will switch to this protocol (provided that there is an active DHCP server of the sixth version).
Judge for yourself, because using this protocol with the provision of a 128-bit address allows you to reserve a lot more addresses than when using the fourth version.
Dedicated Servers
Now consider dedicated servers. The designation speaks for itself: they are intended for some specific tasks. Roughly speaking, this is a real virtual server of the virtual type, completely owned by the user who rents it. This is the meaning of hosting, when the owner of the main resource podcasts can place any information on the allocated space.
In addition, it is not the tenant who is responsible for security, but the one who leases server space. There are quite a few examples of such servers. Here you have mail, games, file sharing, and personal pages (not to be confused with accounts on social networks and services of this type), and much more.
Local networks
A local network, or, as it is often called, a “lokalka”, is organized to unite a limited number of terminals. The architecture of the local network in the sense of connection, as already clear, can be both a wired connection and VPN access. In both cases, a connection to the main administrator server is required. Network services in this case can work in a double mode: with automatic identification (assigning an address to each machine) or with manual entry of parameters.
Local networks, in principle, have a distinctive feature, consisting only in the fact that any terminal needs registration (which is not required, for example, in peer- to -peer networks) and a central server (plus admin). In addition, access to “shared” information can be either full or limited. It all depends on the settings. However, even if you look at the so-called cloud services, they, in fact, also constitute a virtual network, where users, having authenticated, get rights to access certain information, download or edit files, etc. With all this sometimes it is even possible to simultaneously change the contents of a file in real time.
Internet Architecture : A Little History
Finally, we move on to the network, which today is the largest in the world. Of course, this is the Internet, or the World Wide Web. The prototype of the World Wide Web is considered to be ARPANET - communication developed for military purposes in the United States as early as 1969. Then, however, the connection between only two nodes was tested, but over time, a network connection with a cable was established even with terminals located in the UK.
Only much later, when TCP / IP-based authentication and a domain naming system appeared, and what we now call the Internet came about.
In general, it is believed that on the Internet there is no single central server where all information could be stored. Yes, to date, and disk drives of such capacity does not exist. All information is distributed between hundreds of thousands of individual servers of various types. In other words, the Internet can equally be attributed to both peer-to-peer and hybrid networks. With all this, on a single machine, you can create your own Internet server, which will not only manage the network settings or save the necessary information, but also provide other users with access to it. Wi-Fi distribution - what is not the easiest example?
Basic parameters and settings
As for the parameters and settings, everything is simple. As a rule, manual input of network IP, DNS or proxy servers has not been used for a long time. Instead, any provider provides automatic recognition of a computer or mobile device on the network.
In Windows systems, access to these settings is made through the network properties with the choice of IPv4 protocol parameters (or, if it works, IPv6). As a rule, the settings themselves indicate automatic receipt of addresses, which saves the user from entering data manually. However, in some cases, especially when configuring RDP clients (remote access) or when organizing access to some specific services, manual data entry is mandatory.
Conclusion
As you can see, understanding what the network architecture is, in general, is not particularly difficult. In principle, only the main aspects of the organization of the work of networks were considered here in order to explain to any, even the most unprepared user, this question, so to speak, on fingers. In fact, of course, everything is much more complicated, because we did not touch upon the concepts of DNS, proxy, DHCP, WINS, etc. servers, as well as issues related to software. It seems that even this minimal information is enough to understand the structure and basic principles of the functioning of networks of any type.