---
title: "filter IP AS SERVER In W5500"
url: "https://maker.wiznet.io/forum/15606"
markdown_url: "https://maker.wiznet.io/forum/15606/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "bahmanroshan"
created: "2025-02-23T21:04:03+09:00"
last_activity: "2025-02-25T09:49:59+09:00"
language: "en"
views: 3
replies: 2
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# filter IP AS SERVER In W5500

## Question

Asked by bahmanroshan on 2025-02-23 in Ethernet Chips.

IS IT POSSIBLE TO Filter Special IP As Server To Connect To Client bY w5500 Hardware ?

If Is It Possible , How Can Do It ?

## Replies

### Reply 1 (verified answer) by WIZnet AI assistant (automated answer), 2025-02-23

Yes, it is possible to filter specific IP addresses when using the W5500 hardware as a server to connect to a client. This can be achieved by implementing IP filtering in your application code. The W5500 itself does not have built-in IP filtering capabilities, so you will need to handle this in the software running on your microcontroller or host system. Here is a general approach to achieve IP filtering: 1. **Receive Connection Request:** When a connection request is received, the W5500 will provide the IP address of the client attempting to connect. 2. **Check IP Address:** In your application code, compare the client's IP address against a list of allowed IP addresses. 3. **Allow or Deny Connection:** If the client's IP address matches one of the allowed IP addresses, proceed with establishing the connection. If not, deny the connection. 4. **Implement Logic:** You can implement this logic using conditional statements in your code to check the IP address and decide whether to accept or reject the connection. This approach requires programming on the host system that interfaces with the W5500. You can refer to the W5500 datasheet and programming guides for more details on handling connections and retrieving client IP addresses. For more detailed guidance, you can explore the technical documentation available at [docs.wiznet.io](https://docs.wiznet.io). If you have any further questions or need additional assistance, feel free to ask! WIZnet AI Support Team

### Reply 2 by louis_m, 2025-02-25 (in reply to reply 1)

You're using the W5500 as a server, right?

Unfortunately, there's no way to filter client IPs on the server.

You'll need to check the IP addresses that are connecting separately and implement code to ensure that only the IPs you want are allowed to connect.

Thank you.

---

Source: https://maker.wiznet.io/forum/15606