# ELBs

* **ELBs provides security policies that have predefined SSL negotiation configurations** to use to negotiate SSL connections between clients and your load balancer.
  * If you are using the **HTTPS/SSL protocol for your listener, you can use one of the predefined security policies, or use your own custom security policy**.

* **If you create an HTTPS/SSL listener without associating a security policy, ELBs associate the default predefined security policy, ELBSecurityPolicy-2016-08**, with your load balancer.

![](/files/-MTba0SIwmwQAnmgt96G)

* When you use **TCP for both front-end and back-end connections, your load balancer forwards the request to the back-end instances without modifying the headers**.
  * **After your load balancer receives the request**, it **attempts to open a TCP connection to the back-end instance on the port specified** in the listener configuration.

* Because **load balancers intercept traffic between clients and your back-end instances**, the **access logs for your back-end instance contain the IP address of the load balancer** instead of the originating client.
  * You **can enable Proxy Protocol, which adds a header with the connection information of the client**, such as the source IP address, destination IP address, and port numbers.
    * The **header is then sent to the back-end instance as a part of the request**.

* Take note that **ALBs do NOT support SSL renegotiation for client or target connections**.
  * It is **not capable of re-negotiating or re-spawning an SSL connection** between the load balancer and the target EC2 instances.


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://karansingh.gitbook.io/tutorialsdojo-wrong-answers-aws-sec-spec/review-mode-test-2-90/elbs.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.