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I checked the link above <a href="http://ieoc.com/forums/t/29903.aspx" rel="ugc">http://ieoc.com/forums/t/29903.aspx</a><br />
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&lt;&lt;The main difference is that broadcast frames are by nature meant to be sent to all ports in the specific VLAN&gt;&gt;<br />
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Ok the Broadcast is clear <br />
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the Unknown Unicast is not clear , on the same site it says :<br />
&lt;&lt;&nbsp;while unknown unicast are only initially sent to all ports - once the outgoing port is learned, the switch will only forward it out the port where the receiver is located.&gt;&gt;<br />
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Initially sent to all ports ? are all ports on the switch or all ports on the same VLAN ?<br />
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Not clear yet
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all ports just like a broadcast packet. it is so it can learn the path and port for future reference.
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so where is the difference between Unknown Unicast and Broadcast?
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The packet header is different
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<blockquote>
The packet header is different
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How is it different? can you please elaborate a little bit on that ?
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Predrag's comment was a real life scenario rather than a textbook answer
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<div class="content wysiwyg-content">
I have encontered some words that are not really clear to understand such as:<br />
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Unknown Unicast, is it a Broadcast ?<br />
Unknown Multicast ?<br />
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any clarifications ?<br />
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Thank you
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I have encontered some words that are not really clear to understand such as:

Unknown Unicast, is it a Broadcast ?
Unknown Multicast ?


any clarifications ?

Thank you

UNKNOWN /Unicast-Multicast and Broadcast Terminology

A router is a networking device that forwards data packets between computer networks. Routers perform the "traffic directing" functions on the Internet. The most familiar type of routers are home and small office cable or DSL routers that simply pass data, such as web pages, email, IM, and videos between computers and the Internet. More sophisticated routers, such as enterprise routers, connect large business or ISP networks up to the powerful core routers that forward data at high speed along the optical fiber lines of the Internet backbone. Though routers are typically dedicated hardware devices, use of software-based routers has grown increasingly common.

Routers

A switch is a device that filters and forwards packets of data between LAN segments. Switches operate at the data link layer or the network layer of the Open Systems Interconnection (OSI) Reference Model and therefore support any packet protocol. LANs that use switches to join segments are called switched LANs or, in the case of Ethernet networks, switched Ethernet LANs. A hub is a connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports; when a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.

Switches / Hubs

Networking is the process of connecting computing devices, peripherals and terminals together through a system that uses wiring, cabling or radio waves that enable their users to communicate, share information and interact over distances. Often associated are issues regarding operating systems, hardware and equipment, cloud and virtual networking, protocols, architecture, storage and management.