Hey guys , I\u2019m Rocky. This may seem sudden, but have you ever thought about what an IP address is?
When you use a smartphone or computer, you can connect to the Internet without even thinking about it, and you can watch YouTube or upload photos to Instagram. But how can you communicate correctly no matter where you are in the world?<\/p>\n
The key to this is\u00a0the IP address<\/strong>\u00a0. An IP address is like an \u201caddress\u201d on the Internet, and is essential for data to reach the correct destination. However, knowing IP addresses can give you a deeper understanding of how the Internet works and make it easier to identify the cause of network problems.<\/p>\n In this article, we will explain the role and types of IP addresses, and how they are assigned, as clearly as possible. For ease of explanation, this article assumes that IP addresses are IPv4. Although it does not touch on IPv6, we hope you will continue reading to understand the mechanisms that are familiar to you. <\/p>\n If you want to deep dive into Networking make sure to explore our computer networking<\/strong> <\/a>book that is beginner friendly and written in a way for you guys to understand at ease<\/p>\n An IP address is like an \u201caddress\u201d on the Internet. When a smartphone or computer connects to the Internet, an IP address is assigned to each network, enabling it to send and receive data.<\/p>\n For example, when you open a website on your smartphone, the communication takes place as follows:<\/p>\n \u2460 \u201cI want to view this site!\u201d A data request is sent to the IP address of the web server. Without an IP address, you wouldn\u2019t know where to send your data and you wouldn\u2019t be able to open the website.<\/p>\n Did you know that there are several types of IP addresses? There are several types of IP addresses, but the first thing you need to know These two have very different roles in terms of \u201cwhere they are used\u201d and \u201chow far they reach.\u201d Here is a table summarizing the differences between them.<\/p>\n Comparison itemsGlobal IP addressPrivate IP addressesApplicationsUsed throughout the internetFor use in home and corporate networksAddress UniquenessUnique in the world (no duplicates)Unique within the same networkCommunication rangeCommunication across the internetCommunication is possible only within a private networkAdministratorISPs (Internet Service Providers) and cloud providersHome and corporate network administrators<\/p>\n As mentioned above, a global IP address is a public address that can be used to communicate from anywhere in the world, But doesn\u2019t that alone seem a bit strange to you?<\/p>\n When we use the Internet at home, in most cases, our devices are assigned private IP addresses. To unravel this mystery, let\u2019s think about it in terms of a real address.<\/p>\n Global IP address \u2192 \u201cAddress of an entire city, town, or village\u201d<\/strong><\/p>\n For example, suppose A wants to send a letter to B via school. However, this address alone does not tell you who the package is addressed to. Private IP address \u2192 \u201cClassroom and seat number in school\u201d<\/strong><\/p>\n For example, let\u2019s say that Person B is seated in \u201c2nd year, class 3, seat number 15.\u201d In this way, in a situation like that shown above, the information \u201cMr. B at School B\u201d alone is not enough to accurately deliver a letter to Mr. B from outside.<\/p>\n So far, we have learned that in order to communicate with the outside world, you need an \u201caddress (= global IP address)\u201d. This is where the address conversion mechanism known as\u00a0NAT<\/strong>\u00a0(Network Address Translation) comes in . The key component that supports this mechanism is the router.<\/p>\n The router functions like an \u201coffice\u201d in a school. For example, when Person A tries to access the outside world, the communication (letter) is first passed to School A\u2019s router (= office)Because private IP addresses cannot be used to communicate with the outside world, the router converts the sender information (IP) into a global IP address and sends it out onto the Internet based on information about which device is trying to send what kind of communication.<\/p>\n This allows external services to know \u201cwhere the communication came from\u201d through the global IP address. <\/p>\n In this way, NAT converts a private IP to a global IP when sending, and converts the global IP to a private IP when receiving, so that the data can be delivered correctly to the terminal.<\/p>\n This conversion process is usually performed automatically by network devices such as routers, which act as a bridge between home and school networks and the Internet.<\/p>\n Next, we will explain the difference between a \u201cfixed IP address\u201d and a \u201cdynamic IP address\u201d.<\/p>\n Comparison itemsStatic IP addressDynamic IP AddressIP address fluctuationsAlways use the same numberChanged at a certain timeApplicationsServer operation, remote accessHome Internet ConnectionsManagementContract with an ISP to get a fixed IP addressISP automatically changes and assigns<\/p>\n In most home internet networks, dynamic IP addresses are automatically assigned by the ISP (Internet Service Provider). Dynamic IP addresses are a widely used mechanism to simplify network administration[1], On the other hand, there are times when using a fixed IP address is recommended for companies and server operations. So far, we have introduced that there are various types of IP addresses, each with different uses and allocation methods. But doesn\u2019t this raise a question? In fact, there is a global management system for IP address allocation to ensure the harmonious operation of the entire Internet. For example, to use a fixed IP address, you need to sign a contract with an ISP (Internet Service Provider). International organizations are involved in the management of IP addresses. RIRs manage IP addresses in their respective regions. caseAllocation processCountries with NIRIANA \u2192 RIR \u2192 NIR \u2192 LIR \u2192 Individual\/CorporateCountries without NIRIANA \u2192 RIR \u2192 LIR \u2192 Individual\/Corporate<\/p>\n
However, since we don\u2019t usually use it without thinking about it, there are probably many people who have heard of it but don\u2019t really understand it.<\/p>\n
The purpose is not to cover everything, but to serve as an \u201centrance<\/strong>\u201d for beginners to the basics of networking.<\/p>\n<\/a>What is an IP address?<\/h1>\n
<\/a>Why do we need IP addresses?<\/h3>\n
\u2461 The web server sends the data to the requested IP address.
\u2462 The web page can be displayed on the device.<\/p>\n<\/a>IP Address Type<\/h1>\n
The two most well-known types are global IP addresses and private IP addresses.
In addition to these, there are also classifications such as fixed IP addresses and dynamic IP addresses. These are important factors that affect the differences in how IP addresses are assigned.
You may be wondering, \u201cDynamic? IP addresses are \u201caddresses,\u201d so can they change?\u201d
From here, we will explain each type in order.<\/p>\n<\/a>Global and private IP addresses<\/h3>\n
is the difference between a global IP address and a private IP address.<\/p>\n
In fact, even when we use the Internet on a daily basis, we use these two different services without even realizing it.<\/p>\n
whereas a private IP address is a closed address that is used only within a specific network, such as a home or company.<\/p>\n
When our smartphones and computers are connected to our home Wi-Fi, they are actually assigned private IPs.
However, in reality, they also connect to \u201cexternal\u201d services on the Internet, such as YouTube and news sites.
The table says \u201cPrivate IPs are used within the home and business.\u201d
So how can they communicate with the \u201coutside world\u201d?<\/p>\n
The address of School B, where B is enrolled, is \u201cMarunouchi, Chiyoda-ku, Tokyo,\u201d and can be identified from anywhere in the country.
If this address is known, the letter can be delivered to School B.<\/p>\n
Even if you are told to \u201cdeliver it to B at School B,\u201d you cannot pinpoint which classroom B is in, or in other words, which device it is addressed to.<\/p>\n
This type of seat number\u00a0is information that uniquely identifies Person B\u00a0within School B.<\/strong>
However, this seat number cannot be identified from outside the school (on the Internet), since the same number may exist at other schools.<\/p>\n
So how does the actual communication take place?<\/p>\n<\/a>The role of the router<\/h3>\n
When a student (= a computer or smartphone) wants to send a message (= communication) to the outside world, the message is first collected by the router on campus.<\/p>\n
It is also possible to convert a global IP address to a private IP address<\/p>\n<\/a>Static and Dynamic IP Addresses<\/h3>\n
No special settings are required on the user\u2019s side, and an unused IP address is automatically assigned each time the user connects.<\/p>\n
allowing ISPs to efficiently utilize limited IPv4 address resources by automatically assigning and reusing unused addresses.<\/p>\n
Being able to connect using the same IP address at all times leads to improved security and reliability, such as access restrictions and stable operation of web servers.
Setting a fixed IP address allows you to set it up to allow access only from a limited number of IP addresses, which helps to ensure safe access to internal systems and prevent unauthorized access.<\/p>\n<\/a>IP Address Allocation<\/h1>\n
Among them, global IP addresses are essential for communicating with the \u201coutside world\u201d of the Internet, and must be uniquely assigned to devices around the world.<\/p>\n
\u201cWho on earth is managing so many IP addresses, and how?\u201d
\u201cIf each provider in each country distributes them as they please, won\u2019t there be duplication?\u201d<\/p>\n
This system is how we receive the correct IP addresses.<\/p>\n
However, the IP address itself is not something that the ISP just creates.
Let\u2019s take a look at how IP addresses are managed and who manages them.<\/p>\n<\/a>How IP Address Management Works<\/h2>\n
From here, let\u2019s take a look at the diagram to see the overall picture of how IP addresses are managed and assigned. It
may seem a little complicated at first glance, but we will explain the terms that appear in the diagram (IANA, RIR, NIR, LIR, etc.) in order, so please read on without worry.
In order to ensure that IP addresses are unique, a management system is necessary.
This role is played by the Internet Assigned Numbers Authority (\u00a0IANA<\/strong>\u00a0).
However, it is difficult for IANA to directly manage all IP addresses in the world. For this reason, IANA has divided the world into five regions and\u00a0established\u00a0RIRs<\/strong>
(Regional Internet Registries) to manage each region .<\/strong><\/p>\n
However, even with five regions, there are still many countries, making it difficult for the RIRs to manage them alone.
For this reason, some regions have established National Internet Registries (\u00a0NIRs<\/strong>\u00a0) and introduced a system of managing addresses on a country-by-country basis.
The existence of NIRs allows smooth communication between RIRs and LIRs, and allows for smooth allocation.<\/p>\n