Many users doubt whether it is worth to buy proxy or to use free versions. IPv4 addresses are of two types: public and private. The former are also often called white, or external, and the latter, gray or internal. What is the difference between them?

Public addresses are unique and can not be repeated anywhere and never, which is controlled by the provider who leased them to you, and he, in turn, leased them to another provider or IANA organization that monitors the distribution of addresses. And private ones, on the contrary, can be used by anyone and repeated as many times as desired. That is, private addresses can be repeated and not be unique, but at what cost? Nothing can be sent to them from the Internet. Nobody on the Internet knows the route to your private addresses, as well as to possibly the same addresses used by your neighbor, and since no one knows what difference does it make whether they repeat or not? In other words, outside the local network, private addresses are not routed.

There are not so many private addresses – why do a lot if you can repeat them as many times as necessary (on different local networks, of course).

Only three ranges of private addresses: (that is, everything that starts at 10.); (that is, from through inclusive); (i.e., from through inclusive).

Naturally, you are unlikely to need a net-sized network of such large sizes, so private addresses are usually divided into subnets using a longer prefix, for example, from the third range you can get 255 private subnets with 254 hosts each.

The next important question – let’s say we gave many private addresses to employees in the office, but how will they use the Internet?

They will send requests to the network, and responses to these requests will have to be returned to return addresses, which in this case are private. Since no one knows the routes to private addresses on the Internet, this is not possible.

As a rule, this problem is solved in one of two ways:

  1. The network uses a proxy server. This server has an interface in the external network and can also have an interface in the private one. Users access it, not the sites directly. The server is “own”, so it knows about its private addresses. It receives requests from them, and for each request it contacts the Internet from its public address. When it receives the answer, it will send it inside to the private address of the questioner.
  2. You can configure address translation (NAT) on the border router. And then when passing a packet from a local network to the Internet, the sender’s address will change: instead of an unknown private person, the public address will be entered from a certain address pool, or the router’s public address (different implementations are possible here). Answers from the Internet will be sent to this address. In the responses, a reverse replacement will occur: the recipient’s public address will be replaced with the original private address, after which the packet is returned to the client who made the request.

The proxy server is used to replace the local ip-address of the user, thereby ensuring anonymity. As a result, the Internet resources on which software is installed to determine your location will not be able to calculate it. You can buy proxy here

Private proxies are the great option because they can ensure total anonymity in the network. In this way, you can use proxy server in different directions. Some of them are social media marketing, search engine optimization, online games, bypassing regional blocks etc.