When we buy cloud hosts, whether it is domestic Alibaba Cloud or Google cloud host Amazon

Virtual Private Cloud (VPC)

When we buy cloud hosts, whether it is domestic Alibaba Cloud or Google cloud host Amazon, ARM hostingwe will encounter a concept of creating hosts in the purchase process: VPC. What is a VPC and why do I need to configure one when creating a host?

VPC stands for Virtual Private Cloud. In Chinese, some are called private network, and some are called private network. The core is that one or more machines (or other resources) that you can buy can be partitioned into a private network, isolated from other users. You can also isolate your own machine with multiple resources (if you need to). VPC is a technology that accompanies cloud computing. It is created to solve the functions, security, and flexibility that traditional networks cannot meet in the cloud environment.

VPC Origin

General networks, such as our home network, Cloud platfrom provider will configure the information network in the router for the address segment, such as the common 192.168... , or 10.*.*.*. When there is a computer or mobile phone access to the router, the router will assign these teaching equipment resources to the students as an IP address in a network segment, these system devices are in this network segment (subnet), the development of the relationship between our own home devices can learn to communicate with each other, the computer company can see the photos in the NAS, the mobile phone market can project the screen to the TV.

What if it's in the machine room? virtual private cloudThe server is connected to the switch, and the router is connected to the switch. Servers in the same router can communicate with each other. To be isolated, just as servers of different users under a router are isolated or servers of different services of the same user are isolated from each other, you can create a VLAN for each server to be isolated so that servers in the same vlan can communicate with each other, but servers in different vlans cannot communicate with each other.

What about cloud computing? Common vlans cannot meet the requirements of cloud computing.

The number of vlans is limited. Only 4000 vlans can be created.

The volume of cloud computing is large, the number of users is far more than 4000, and some users only have one or two hosts, and the number limit is even more difficult.

Vlan configuration is complex and inflexible.

Limited by the students' physical knowledge network, it is not possible to cross geographical spatial locations. If the server in machine room A and the db server in machine room B are the same enterprise business, we need to be divided into the same social network, vlan is also impossible in China.

To that end, Amazon, the leading cloud computing company, first used VPC technology in 2010 (though it wasn't called VPC at the time). The current VPC is basically based on overlay technology, built on top of a three-layer network, to achieve a two-layer network.