Qual è il mio indirizzo IP?

What is an IP address and why does it matter?

‘IP’ stands for Internet Protocol, which is the set of rules that makes it possible for devices to communicate over the Internet. With billions of people accessing the Internet every day, unique identifiers are necessary to keep track of who is doing what. The Internet Protocol solves this by assigning IP numbers to every device accessing the Internet.

A computer’s IP address is like the physical address of a house. If someone calls a pizzeria to order a delivery, they need to provide their physical address. Without that address, the pizza delivery person will have no idea which house to deliver the pizza to.

For example, when a user types a domain name, like google.com, into a web browser, this will initiate a request to Google’s web server asking for content (the Google homepage). Once Google receives the request, it needs to know where to send the website content. For this reason, the request will contain the asker’s IP address. Using the provided IP address, Google can send a response back to the user’s device, which will then display that content in the user’s web browser.

Il sistema che coordina tutto questo è chiamato DNS. Funziona come una rubrica telefonica per gli indirizzi IP in modo che gli utenti possano accedere ai servizi Web utilizzando nomi di dominio compatibili con la lettura umana. Ad esempio, quando un utente digita un nome di dominio, ad esempio ‘facebook.com’ nella finestra del browser, inizia una query DNS che alla fine porta a un server DNS che traduce il nome di dominio in un indirizzo IP.

What do IP addresses look like? These addresses have a different format based on whether they are IPv4 or IPv6.

What is the difference between IPv4 and IPv6?

IPv4 and IPv6 are different versions of the Internet Protocol. IPv4 was implemented in 1983 and is still in use today. The format for IPv4 addresses is four sets of numbers separated by dots, for example: ‘192.0.2.1’. This is a 32-bit format, which means that it allows for 2³², or about 4.3 billion, unique IP addresses, which it turns out is not enough for the amount of devices that are now on the Internet. The need for more IP addresses led to the implementation of IPv6.* IPv6 addresses use a more complex format that utilizes sets of numbers and letters separated by single or double colons, for example: ‘2001:0db8:85a3:0000:0000:8a2e:0370:7334’. This 128-bit format can support 2¹²⁸ unique addresses. (That computes to a 39-digit number!)

IPv6 provides some other updates to IPv4, including security and privacy improvements. Despite their differences, both IPv4 and IPv6 have been used concurrently on the web for over a decade. The two versions can run in parallel, but special measures had to be implemented to facilitate communications between IPv4 and IPv6 devices. This compromise had to be made because so much of the web is still running on IPv4 addresses.

*Cos'è successo all'IPv5? IPv5 è stato un protocollo di dati sperimentale in streaming che non è mai stato implementato. Utilizzava la stessa formattazione a 32 bit di IPv4, quindi non ha risolto adeguatamente il problema di non avere abbastanza indirizzi IP univoci. Per questo motivo, IPv6 è diventato il legittimo successore di IPv4.

What is the difference between static IPs and dynamic IPs?

L'offerta limitata di indirizzi IPv4 ha portato all'introduzione di un'assegnazione dinamica degli indirizzi IP, che è ancora una pratica molto comune. La maggior parte dei dispositivi connessi a Internet viene assegnata a indirizzi IP temporanei.

Ad esempio, quando un utente di casa si connette a Internet sul proprio computer portatile, l'ISP dell'utente gli assegna un indirizzo IP temporaneo da un pool di indirizzi IP condivisi. Questo indirizzo IP è noto come indirizzo IP dinamico. Ciò è più conveniente per l'ISP rispetto all'assegnazione di un indirizzo IP permanente o statico a ciascun utente.

Some ISP customers, such as large enterprises, will pay to maintain a static IP address (for example, Cloudflare’s 1.1.1.1). However, for most users, having a dynamic IP address is sufficient. When hosting a web server, such as a self-hosted website, API, or gaming server, a dynamic IP address can create problems. A change in IP address can cause their DNS queries to fail, effectively taking the resource offline. Luckily, this issue can easily be corrected with Cloudflare’s dynamic DNS.