EIP
Elastic IP is a kind of NAT IP, by binding with server, NAT mapping between Elastic IP and private address of server, to realize the communication between server and public network.
Network Services
network service provides EIP, NAT gateway, DNS resolution, etc.
NAT Gateway
NAT gateway can provide IP address translation function for servers in public cloud VPC network, so that servers can access external network or provide Internet services.
DNS
DNS is used to resolve simple and memorable domain names into IP addresses for computer communication, so that users can easily access specified URLs or servers through domain names, etc.