
Explanation
Box 1: AGW1
Azure Application Gateway offers a web application firewall (WAF) that provides centralized protection of your web applications from common exploits and vulnerabilities. Web applications are increasingly targeted by malicious attacks that exploit commonly known vulnerabilities. SQL injection and cross-site scripting are among the most common attacks.
Box 2: ELB1
Public IP addresses allow Internet resources to communicate inbound to Azure resources. Public IP addresses also enable Azure resources to communicate outbound to Internet and public-facing Azure services with an IP address assigned to the resource.
Note: In Azure Resource Manager, a public IP address is a resource that has its own properties. Some of the resources you can associate a public IP address resource with are:
* Virtual machine network interfaces
* Internet-facing load balancers
* VPN gateways
* Application gateways
References:
https://docs.microsoft.com/en-us/azure/application-gateway/waf-overview
https://docs.microsoft.com/en-us/azure/virtual-network/virtual-network-ip-addresses-overview-arm