Selecting Networking Solutions for Workloads

1. What CIDR address ranges should you use for your VPC?
The range you choose for your VPC should be large enough to host all of the available instances that you will need for your application stack.

2. Why do you need more than one VPC?
You should use separate VPCs for development, testing, and production environments.

3. Why should you avoid using public subnets for your web servers?    
There is no good reason for using public IP addresses for your web servers. Instead, locate your web servers behind load balancers hosted on public subnets. Your web servers should be hosted on private subnets that protect your web servers from direct Internet access.

4. Can your existing public IP addresses be moved to AWS?
You can move your public IP addresses to AWS by using a bring-your-own IP (BYOIP) address service.

5. What AWS networking services can replace existing hardware devices?
All networking services provided by AWS are software services. For example, routers and load balancers and all network services are software appliances.

6. What can network ACLs do that a security group cannot do?
A network ACL has the ability to block a specific IP address, and a security group does not.

7. Why would you use elastic IP addresses?    
Elastic IP addresses can be used to add static public IP addresses to an EC2 instance or can be assigned to a NAT gateway service.

8. How can Direct Connect help your VPN connections with multiple VPCs in different AWS regions?
A Direct Connect gateway can allow you to connect to multiple VPCs in different AWS regions to provide high-speed connectivity.