Suggest an editImprove this articleRefine the answer for “What is a broadcast MAC address?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)**A broadcast MAC address** is the special MAC address `FF:FF:FF:FF:FF:FF`, meaning the frame is sent to all devices within a single local network. **Key point:** broadcast does not pass through routers and is limited to a single broadcast domain.Shown above the full answer for quick recall.Answer (EN)Image**A broadcast MAC address** is a **special MAC address** that means the frame is sent to **all devices within a single local network**. Put simply: **broadcast = "one → all"**. --- ## What a broadcast MAC address looks like The broadcast MAC address **is always the same one**: ``` FF:FF:FF:FF:FF:FF ``` - all 48 bits = `1` - there is **no other version** of a broadcast MAC --- ## How broadcast works at the data link layer 1. The device sends a frame with the destination MAC address `FF:FF:FF:FF:FF:FF` 2. The switch: - **sends the frame out on all ports** (except the incoming one) 3. **Every device** on the network: - receives the frame - checks it - decides whether it needs it or not --- ## Why broadcast is needed Broadcast is used when: - the sender **does not know the recipient's MAC address** - the message needs to be delivered **to everyone on the network** Typical examples: - an **ARP request** - service announcements on the network - some device discovery protocols --- ## Limitations of broadcast Important for an interview: - broadcast **does not pass through routers** - it is limited to **a single broadcast domain** - a large amount of broadcast traffic: - loads the network - reduces performance --- ## Comparing MAC address types | Type | Who it is sent to | |---|---| | Unicast | one device | | Multicast | a group of devices | | **Broadcast** | all devices | --- ## Short version for an interview > **A broadcast MAC address** is the MAC address `FF:FF:FF:FF:FF:FF`, used to send frames to all devices within a single local network.For the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.