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Questions tagged [broadcast]

Broadcast refers to sending a message to all devices on the same LAN.

Ethernet can communicate point to point (with a specific ARP address as destination and source) or it can broadcast to all devices on the same LAN.

Examples of that are DHCP requests and ARP requests.

On Super User this tag does not refer to TV broadcasting.

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Problem playing games using OpenVPN that use broadcast packets. Other games work, hosts can ping each other

I'm running an OpenVPN server in bridged mode and clients can successfully connect, see shared folder and play LAN games that let you enter the LAN IP address. However I'm unable to play games like Sacred Underworld I believe because it sends out…
Coder
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What is ICMP broadcast good for?

To configure Linux to ignore ICMP broadcasts (to protect from SMURF attacks), I have added the following line to /etc/sysctl.conf: net.ipv4.icmp_echo_ignore_broadcasts = 1 Anyone knows what are the drawbacks of ignoring ICMP broadcasts? In other…
brahima
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Unable to ping broadcast address

Host address: 192.168.0.13 Network: 192.168.0.0 255.255.255.0 Router: Cisco DPC3825 DOCSIS 3.0 Gateway (user manual) My home network uses the 192.168.0.0 /24 network for my (mostly wireless) devices. On many other networks I frequent, I'll ping…
root
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From where do I get a reply if I ping broadcast address 255.255.255.255 from a router

When I do a ping to the broadcast address, I get reply from self-loopback 127.0.0.1. Is this scenario correct or should I get reply from the longest-prefix IP? ping 255.255.255.255 PING 255.255.255.255 (255.255.255.255): 40 data bytes 68 bytes from…
Praveen
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Understanding DHCP discovery specific subnet

I am learning networking and in class we are talking about DHCP. I understand that when a host just joins a network it does not have an ip yet so it sends out a dicovery message. we are using wireshark to see the in's and out's of the DHCP message.…
Peter Sun
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Windows IP address cached even after cable unplugged?

I have a PC which connects to a network by both wired cable and wireless. Of course, it has 2 IP Addresses : 192.168.5.111 and 192.168.5.112. (Subnet mask 255.255.255.0) As usual, the PC picks the wired-IP(192.168.5.111) as its main-IP while the…
David Tran
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Broadcast address in IPV4

I have a small network with the subnet mask 255.255.255.240 and the IP range is 192.168.2.1 - 192.168.2.12. From 192.168.2.1, I want to broadcast a packet. I don't want this packet to go anywhere outside this subnet. After reading several basic…
PermanentGuest
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Is it possible to get a router’s IP address from a Wi-Fi signal?

Is it possible to get a router’s IP address from a Wi-Fi signal without having to connect in, given that it's broadcasting Wi-Fi, but requires a WPA password?
Sandfrog
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Send broadcast message on user login

I'd want to add a new feature to my Red Hat 5 so when any user opens a ssh remote session a broadcast message gets delivered to a defined user/all users. How to do it?
Pedro Montoto García
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OpenWRT Broadcast Packet Forwarding

I am trying to forward broadcast packets from one LAN to another LAN using OpenWRT. My setup looks like this: (Netgear R6080 Router, OpenWrt SNAPSHOT r20168-b2681e584c / LuCI Master git-22.203.79817-25dcd0b) I've got port forwarding set up between…
Alex Charters
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Synology NAS Hibernation issues due to SMB broadcasts

I'm another user going around this merry-go round again. I purchased a Synology NAS DS718+, installed Plex and Docker (calibre-web-server), and have found the NAS is never sleeping. After looking at Synology's own advice for Hibernation issues, I…
davidhood2
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IPv6 link-local multicast vs. IPv4 broadcast

I know that there is no broadcast in IPv6. However, there is the concept of link-local multicast using the ff02::1 IP address, reaching all hosts in the very same local network. So what is the difference between ff02::1 and IPv4 broadcast? Since…
user1816723
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Script/program that listens for user input, reads logs for output and sends broadcast

During code deployments there is a risk of service/system failures. The Network Operations Center monitors alerts from servers. If the alert comes as a result of a code deployment then it might not be anything to be concerned about. If however…
Wings
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Why broadcast ping takes longer than host ping

I have a simple question. I have read that when I'm pinging broadcast address in LAN every device responds to ICMP Echo Request and console shows first(quickest) response. But when I pinged broadcast response time was about 10 times longer than…
some_ONE
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How to use a key binding within shell script ? (Launch terminator in broadcast mode in background)

I currently use a small shell script to start a terminator window as a background process which has multiple splits specified with a layout. terminator --layout=My_layout & I want to execute a command to connect to a remote server in all the…
Suvarna Pattayil
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