Application Gateway (Layer 7) in Azure - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is an Azure Application Gateway?

Azure Application Gateway is a web traffic load balancer that operates at Layer 7 (the application layer). It helps manage traffic to web applications by routing requests based on URL paths, host headers, and more.

beginner

What does Layer 7 mean in the context of Application Gateway?

Layer 7 refers to the application layer in the OSI model. It means the gateway can inspect and route traffic based on content like URLs, HTTP headers, and cookies, not just IP addresses or ports.

intermediate

How does Application Gateway improve security for web applications?

It can integrate with a Web Application Firewall (WAF) to protect against common web attacks like SQL injection and cross-site scripting, helping keep applications safe.

intermediate

What is path-based routing in Application Gateway?

Path-based routing lets the gateway send requests to different backend servers based on the URL path. For example, requests to '/images' can go to one server, while '/videos' go to another.

intermediate

Why would you use SSL termination with Application Gateway?

SSL termination means the gateway decrypts incoming HTTPS traffic, so backend servers get plain HTTP. This reduces the load on backend servers and lets the gateway inspect traffic for routing or security.

What layer of the OSI model does Azure Application Gateway operate on?

A Layer 7 - Application Layer

B Layer 3 - Network Layer

C Layer 4 - Transport Layer

D Layer 2 - Data Link Layer

Azure Application Gateway works at Layer 7, allowing it to route traffic based on application-level information like URLs and headers.

Which feature allows Application Gateway to send requests to different servers based on URL paths?

A DNS resolution

B IP-based routing

C Path-based routing

D Port forwarding

Path-based routing lets the gateway route requests depending on the URL path, directing traffic to specific backend pools.

What is the main benefit of enabling SSL termination on Application Gateway?

A It encrypts traffic between backend servers

B It decrypts HTTPS traffic at the gateway, reducing backend load

C It disables HTTPS for faster connections

D It blocks all HTTP traffic

SSL termination decrypts incoming HTTPS traffic at the gateway, so backend servers receive unencrypted traffic, reducing their processing work.

How does Application Gateway enhance security for web apps?

A By integrating with a Web Application Firewall (WAF)

B By blocking all incoming traffic

C By encrypting backend databases

D By disabling user authentication

Application Gateway can include a WAF to protect web apps from common attacks like SQL injection and cross-site scripting.

Which of these is NOT a routing method supported by Application Gateway?

A Path-based routing

B Host-based routing

C IP address-based routing

D MAC address-based routing

Application Gateway does not route based on MAC addresses; it supports path-based and host-based routing among others.

Explain how Azure Application Gateway routes web traffic and why operating at Layer 7 is important.

Think about how a traffic director decides where to send cars based on their destination signs.

Describe the security benefits of using Application Gateway with a Web Application Firewall.

Imagine a security guard checking visitors before they enter a building.