Questions tagged [broadcast]
For questions about broadcasting in computer networking. Use this tag when you are troubleshooting or configuring network devices in relation to broadcast.
161 questions
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Unknown MAC address data frame flooding by switch
Let's say switch A has 2 switches connected at port 2 & port 4. There are a total of 8 ports.
With time, it knows the MAC address of other devices connected to it.
Now, the device on port 1 wants ...
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Switch Module on a Router
I have configured spanning tree on switch A.
I can show the spanning tree and it is running on switch A
The 2 interface does not form an etherchannel, they are individual port
There are no broadcast ...
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Allowing broadcast through a Cisco 5508
We recently installed WiFi thermostats that connect to a Delta eBMGR, which is connected via ethernet. They utilize the BACnet protocol, which is broadcast traffic. They are on their own subnet, but ...
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DHCP packets in a Wi-Fi network (WEP2-Personal)
The DHCP packets with the message type Discover, Offer, Request and Acknowledge use the L2 broadcast address for communication (even in the Acknowledge packet which has an IP destination of the newly ...
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point-to-point or broadcast network : concrete case
What concrete rule or layer of the OSI model should be used to decide whether a network is a point-to-point network or a broadcast network?
A general definition (*) seems clear, but in practice it ...
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Why isn't my computer flooded with Beacon frames?
I used Wireshark to capture IEEE 802.11 Beacon frames in promiscuous mode. I see frames from about a dozen of AP's around me.
But I receive them only once in a few seconds, despite AP's having beacon ...
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Why is 10.1.255.255 an invalid broadcast address?
I’ve been following the CCENT official certification book(100-105) and came upon this question in the “do I know this already?” quiz. The books only covered /24 subnetting only so far.
Which of the ...
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Is a DHCP offer packet a broadcast or unicast?
DHCP OFFER is a layer3 broadcast because the server doesn't know the client's IP, but the server knows the client's MAC address. So why does it send the OFFER as L2 broadcast?
If anyone ask me about ...
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WHY and HOW do routers and vlans break broadcast domains?
Everybody says routers (and vlans) break broadcast domains, but nobody goes into WHY that is, it seems.
What's the router logic?
Say I have three routers on my lan, with one main router and the ...
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Ethernet frame's source mac-address out of a port in an ARP request forwarded to an interconnected switch towards an end host
PC1 ----- (P1) SWITCH1 (P2) ----- (P2) SWITCH2 (P1) ----- PC2
Assume two network switches SWITCH1 and SWITCH2 are interconnected to each other through their ports P2 respectively present on each ...
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What is the difference between broadcasting and flooding?
In the Open Shortest Path First routing algorithm, the information about connected links is "flooded" throughout the network.
How is flooding different from broadcasting?
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Pinging broadcast address [closed]
I am using Linux. I read somewhere on the internet that pinging the address 255.255.255.255 will ping everyone in the network segment. And it will return every IP addresses in that subnet. But when I ...
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very strange broadcast in LAN with Cisco ASA
Today i have detected Cisco ASA 5505 CPU usage went to 100% and LAN was flood with broadcast (ff:ff:ff:ff:ff) going to 10.0.12.255 address, i have noticed all these activity in wireshark that some ...
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Can Directed Broadcasts be forwarded even if the destination is 2 hops away?
I was studying for the CCNA exam and I read this: " When a directed broadcast packet reaches a router that is directly connected to the destination network , that packet is broadcast on the ...
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BACnet broadcasts with 2 subnets on one VLAN
I have a building automation network configuration with mechanical equipment on subnet 10.233.138.0/24 and electrical equipment on subnet 10.233.136.0/23. BACnet uses broadcasts for certain functions ...
