Merge pull request #267774 from jaesoni/slv-vs-appgw

Clarification on SLB vs AGW

Author: prmerger-automator[bot]

articles/application-gateway/tcp-tls-proxy-overview.md

@@ -13,7 +13,7 @@ ms.author: greglin
 
 In addition to the existing Layer 7 capabilities (HTTP, HTTPS, WebSockets and HTTP/2), Azure Application Gateway now also supports Layer 4 (TCP protocol) and TLS (Transport Layer Security) proxying.  This feature is currently in public preview. To preview this feature, see [Register to the preview](how-to-tcp-tls-proxy.md#register-to-the-preview).
 
-## Application Gateway Layer 4 capabilities
+## TLS/TCP proxy capabilities on Application Gateway
 
 As a reverse proxy service, the Layer 4 operations of Application Gateway work similar to its Layer 7 proxy operations. A client establishes a TCP connection with Application Gateway, and Application Gateway itself initiates a new TCP connection to a backend server from the backend pool. The following figure shows typical operation.
 
@@ -24,7 +24,14 @@ Process flow:
 1. A client initiates a TCP or TLS connection with the application gateway using its frontend listener's IP address and port number. This establishes the frontend connection. Once the connection is established, the client sends a request using the required application layer protocol. 
 2. The application gateway establishes a new connection with one of the backend targets from the associated backend pool (forming the backend connection) and sends the client request to that backend server. 
 3. The response from the backend server is sent back to the client by the application gateway. 
-4. The same frontend TCP connection is used for subsequent requests from the client unless the TCP idle timeout closes that connection. 
+4. The same frontend TCP connection is used for subsequent requests from the client unless the TCP idle timeout closes that connection.
+
+### Comparing Azure Load Balancer with Azure Application Gateway:
+| Product | Type |
+| ---------- | ---------- |
+| [**Azure Load Balancer**](../load-balancer/load-balancer-overview.md) | A pass-through load balancer where a client directly establishes a connection with a backend server selected by the Load Balancer's distribution algorithm. |
+| **Azure Application Gateway** | Terminating load balancer where a client directly establishes a connection with Application Gateway and a separate connection is initiated with a backend server selected by Application Gateway's distribution algorithm. |
+
 
 ## Features