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Do Bluetooth Devices have MAC address with the same specification as the MAC addresses of the Ethernet and Wi-Fi Network cards?

Bluetooth devices are required to have a unique device address, assigned from the same registry as Ethernet and Wifi MAC addresses. Quoting the Bluetooth specification version 5.0 volume 1: Each ...
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Does Switch need its own MAC address?

The basic function of a switch is transparent bridging - for this, it doesn't need any MAC address of its own. However, if you need to talk to a switch - ie. a managed switch - then that switch ...
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How do we prevent loss of sensitive information from MAC spoofing?

MAC spoofing is more about LAN disruption than stealing information. I think you have a mistaken idea about routers. Routers do not route to MAC addresses, and on a LAN, a router is simply another ...
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7 votes

ICMP packet with correct mac address but wrong ip address

It is as you said. The computer with that MAC address will receive the ethernet frame, since on layer 2 it's all good. Then, looking at layer 3, it will discard the IP packet, since the IP address is ...
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7 votes
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Run MACsec and VLAN in parallel?

Welcome to Network Engineering! There is no standard for MACSec and 802.1Q, so manufacturers have come up with their own solutions. Cisco calls it "WAN MACSec," and does it this way: The WAN ...
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7 votes

Is IP an abstraction

Is your home postal address an abstraction? When someone send you a paper mail, they put your address on the envelope, then put the envelope in the mailbox (the first "router"). Then this mail goes ...
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Layering unicast addressing over multicasts

First part of the question is whether there is a standard that prohibits use of IPv4 unicast addresses with multicast MAC address in an ethernet frame ? The problem here is that you are dealing ...
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6 votes
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What is persistent connection and session

First a word about: I understand word persistent as following : no one else can occupy wire at the time of persistent connection. So this connection is only one-to-one. But this is not right. ...
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6 votes
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Why is RTS/CTS optional for IEEE 802.11?

The reason it is optional is that in 802.11 RTS and CTS are management frames. Management frames are sent at the lowest base/basic/required data rate supported by all clients associated to the ESS, ...
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6 votes

Does Switch need its own MAC address?

Yes, if your switch supports spanning-tree protocol(either legacy spanning tree protocol, rapid-pvst+ or MST) your switch will have a mac address since spanning-tree protocol uses bridgeID to elect ...
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6 votes
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Does MACsec (IEEE 802.1AE) support multicast / broadcast?

MACsec provides security on the point-to-point link level. MACsec and 802.1X sit (more or less) in between the physical layer (L1) and the data link layer (L2). The key management is between the layer-...
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How might I test layer2 latency over ethernet without a target IP address?

The narrow answer is no, there's no "ethernet ping" which is normally implemented. Your network termination unit appears to be a switch, presumably switching between your local copper and fibre ...
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5 votes

Is IP an abstraction

IP is an abstraction, but not the way you're describing it. In the OSI and TCP/IP models, layers abstract the layers below them. For example, an application protocol, like http, just expects a stream ...
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What if receiver changes its IP address during the transmission process?

The data will get lost. At the very latest, the last router in the chain will send a "Who has X" ARP request and get no answer, so it will not be able to deliver the packet. Or, if it still ...
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4 votes

when will an arp table be updated

The RFC doesn't address your second scenario. The reason for this is that Host C sending to Host A may not be on the same network as Host A. Host A having an ARP cache entry in that case doesn't ...
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4 votes

Is there a way to build a functional (sub)network with devices that have the same MAC Address?

Put every device in a different VLAN: device 1: vlan 11, device 2: vlan 12, ... Put a different IP network for each device: device 1: 192.168.1.11/24 device 2: 192.168.2.11/24 ... Then put your ...
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4 votes

Do Bluetooth Devices have MAC address with the same specification as the MAC addresses of the Ethernet and Wi-Fi Network cards?

Bluetooth devices are assigned addresses similarly to Ethernet - an organizationally unique identifier (OUI) of 3 bytes followed by another 3 bytes assigned by the vendor. The Bluetooth address of a ...
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4 votes
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How transparent bridging Wi-Fi with Ethernet works?

You seem to be confusing the different network layers. Routers route packets at layer-3, using the layer-3, e.g. IP, addresses, but bridging happens at layer-2, using layer-2, e.g. MAC, addresses. ...
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4 votes

Is the MAC address pool from which Bluetooth, Wi-Fi, GSM cards etc take their addresses from the same address pool as the ethernet MAC address pool?

Ethernet uses the "MAC-48" address space by IEEE. It is/was used for Wi-Fi, Bluetooth, Fibre Channel, SAS, ATM, Token Ring (and some others) as well. This gives us the opportunity to bridge all of ...
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4 votes

How often does it happen that at the Layer 2 (MAC) an error goes undetected?

Ethernet layer 2 doesn't correct errors, it only detects them by frame check sequence (FCS). The algorithm for FCS is CRC with the polynomial G(x) = x32 + x26 + x23 + x22 + x16 + x12 + x11 + x10 + x8 +...
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4 votes

Packet with wrong source MAC address

Consider the following network, with correct addressing, masks and the obvious routes. B K |.2 |.? 10.0.0.0/24 ===+===+===+================ |.1 R |.1 10.0.1.0/24 ===+...
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4 votes
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Why the ARP packet contains values like "Physical Address length" etc?

From Wikipedia: ARP has been implemented with many combinations of network and data link layer technologies, such as IPv4, Chaosnet, DECnet and Xerox PARC Universal Packet (PUP) using IEEE 802 ...
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What are the most common technologies that the IPv4 or IPv6 run on top of BESIDES the ethernet protocol?

As mentioned in your question about Bluetooth, IP can run over a wide range of underlying transport technologies - many of which are quite dissimilar to Ethernet. There are a bunch of easy legacy ...
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3 votes
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Switches - help me to understand please

If a PC wants to send to another PC through a switch and does not know its MAC address, that means all PCs on network will receive it and see it!! Hosts on a LAN with a protocol that uses MAC ...
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3 votes
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Regarding Encapsulation in OSI layer

Since you're quoting me, allow me to answer your question. I don't think it's contradictory at all. While it's true that tunneling protocols* don't fit the OSI model, the process of encapsulation ...
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3 votes

Assign an IP to a MAC Address to DHCP POOL

On a Cisco IOS DHCP server, it is pretty simple. In the DHCP pool configuration, use the address command to assign an IP address to a MAC address: address <ip-address> hardware-address <mac-...
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3 votes
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Detecting MAC addresses in a shared medium using WLAN/802.11 features

For A to detect B, it has go into "monitor mode" and listen on every channel (there's no guarantee B is even on the same channel) for 802.11 headers. But doing so means A is no longer associated with ...
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3 votes

when will an arp table be updated

I'll try to answer each of your questions, one after the other. But the premise is that an arp entry will get generated on a host, only when it sees an ARP response. Hosts dont typically do mac-...
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3 votes

How transparent bridging Wi-Fi with Ethernet works?

A "self-learning MAC bridge" tracks the MAC addresses from the frames it receives - this way it nows, which frames need to be forwarded to which port. WiFi bridging works the same way. MAC addresses ...
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3 votes

Minimum frame size in ethernet CSMA/CD

sender should be transmitting for at least the 2*PT,where PT is end to end propagation delay. Worst case is between senders that are located at opposite ends of a collision domain. Imagine sender 1 ...
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