---
title: "MAC, IP, GT, SN information"
url: "https://maker.wiznet.io/forum/13714"
markdown_url: "https://maker.wiznet.io/forum/13714/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "Glomumu"
created: "2020-02-20T12:25:20+09:00"
last_activity: "2020-02-27T23:05:53+09:00"
language: "en"
views: 2294
replies: 9
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# MAC, IP, GT, SN information

## Question

Asked by Glomumu on 2020-02-20 in Ethernet Chips.

Hi everyone!

Maybe this is a stupid questions, but I want to be sure about it.

When you initialize W5500 you need to set net information. In mi case, I want to set as an static IP to understand its

I use cmd-> ipconfig/all and cmd->arp -a to see my network information how it works.

With arp -a I can see what IPs are being used, so I can choose one, and with ipconfig, I can see gw and sn, but I don’t sure about what MAC.

I’m electronic student and I’m don’t know too much about ethernet nets. But I’m trying to learn ![:smiley:](https://emoji.discourse-cdn.com/twitter/smiley.png?v=12)

Could someone help me please?

## Replies

### Reply 1 by becky, 2020-02-21

What’s your question?

The MAC address must have a unique address assigned by the IEEE for each device.
Even if you use DHCP rather than static IP, you still need to set the MAC address.

### Reply 2 by Glomumu, 2020-02-21 (in reply to reply 1)

Hi!

I want to know what it’s the MAC of my chip.
In the datasshet I can read “*W5500 enables users to have the Internet connectivity in their applications just by using the single chip in which TCP/IP stack, 10/100 Ethernet MAC and PHY embedded*”
I want to know how to know my ethernet MAC?

Thank you in advance

### Reply 3 by becky, 2020-02-21

WIZnet can’t be a substitute for user’s MAC address.
W5500 is a product without a MAC address. Should write a MAC address directly from the MCU.
Refer to [IEEE SA - IEEE Registration Authority](http://standards.ieee.org/faqs/regauth.html#22)

### Reply 4 by Glomumu, 2020-02-21

Hi!

Thank you!

This MAC could be a “random MAC”. I mean, following the standard. I’m right?

### Reply 5 by becky, 2020-02-23

No, MAC address must be allocated from IEEE.
Mac address must have a unique number for each device, which is managed by the IEEE.

### Reply 6 by Glomumu, 2020-02-25

Hi becky, thanks for your response.

To study and testing Wiznet, I could use a generated MAC, only for testing.

If in the future, I want to sell a product with include W5500, it should have an unique MAC address, using for example, a dvice that provides that MAC, for example, Microchip device’s AT24MAC402. I’m right?

Thank you in advance

### Reply 7 by becky, 2020-02-26

Yes, you need to buy mac address from IEEE or get other way.
You can purchase the MAC address types MA-S, MA-M, and MA-L from the IEEE.

[![image](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/9/9f82a0dbe51f4613f5e00b9e62e86b845d4bd5b1.png) image748×620 43.8 KB](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/9/9f82a0dbe51f4613f5e00b9e62e86b845d4bd5b1.png)

This is Registration Fees of MA-S. You can use a 28
Please refer to link.
<https://standards.ieee.org/products-services/regauth/oui36/index.html>

### Reply 8 by Glomumu, 2020-02-27

OK Becky

Thank you for helping me understand this topic.

### Reply 9 by Mxyxixptlick, 2020-02-27

If your W5500 is NOT sitting on the Internet with no router or firewall in between, you can give it a locally-administered MAC address that costs nothing. Just make sure it’s unique on your LAN. <https://en.wikipedia.org/wiki/MAC_address#Universal_vs._local>

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Source: https://maker.wiznet.io/forum/13714