Multicast refers to one-to-many network transmission options, where packets will be automatically propagated just to those nodes wishing to receive them. IP-based multicast is the common case, though other multicast implementations exist.
Questions tagged [multicast]
1621 questions
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votes
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What is the purpose of SO_REUSEADDR?
I am trying to understand a multicast code, and I don't understand the utilities of a little part :
int fd_socket = socket(AF_INET, SOCK_DGRAM, 0);
u_int yes = 1;
setsockopt(fd_socket, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes));
I don't…
user6125411
5
votes
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Use ip route add to add multicast routes to multiple devices
TLDR: Is there a way to use "ip route" to add multicast routes for multiple NICs?
We have software that joins two sockets bound to different ip addresses on separate NICS to two separate multicast groups, eg socket 1 is bound to 192.168.0.2 and…
gnac
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receive multicast from specific network interface on Linux
I'm trying to receive a multicast data from specific network interface on CentOS 5.5
sd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_port = htons(1234);
addr.sin_addr.s_addr =…
Dima
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In Golang, how to receive multicast packets with socket bound to specific address/port?
Task at hand is to bind a socket specifically to address 1.0.0.2:520 (assigned to eth2), then read multicast UDP packets addressed to 224.0.0.9:520.
I am trying the code below, based on https://godoc.org/golang.org/x/net/ipv4
Unfortunately, result…
Everton
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1 answer
Openwrt allow multicast traffic
I'm running openwrt on a device and have a python script that listens and prints to screen multicast traffic on 239.2.1.1.
However nothing is being printed to the screen and I believe this is a firewall issue.
How do I make sure that multicast…
Steven Lutz
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UDPClient Multicast receive fails on computer with multiple NICs
I've got a computer with multiple NICs - and UDPClient's send method continually fails. Here's the code:
private static void receiveData()
{
recvSock = new UdpClient(PORT);
…
Dan
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3 answers
Is CHANGE_WIFI_MULTICAST_STATE permission and use of WifiManager.MulticastLock required to receive multicast packets on Android?
I have a test app that I'm using to demonstrate whether or not multicast traffic is making it into an Android device. I'm seeing behavior that appears to contradict Google's documentation here and here which implies that two prerequisites need to…
unbrokenrabbit
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Why can't I get UPnP unicast M-SEARCH to work instead of MultiCast M-SEARCH?
Good morning,
We've decided to use UPnP as much as possible. We are using MultiCast on 239.255.255.250:1900 for our M-SEARCH.
However, we're looking at how to handle when a customer has MultiCast locked down on their network. Looking at the UPnP…
Curtis
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2 answers
Netlink Multicast Kernel Group
The task I am trying to achieve is actually quite simple (multicast the string "TEST" to a userland daemon), but the kernel module doesn't compile. It stops with the error:
passing argument 4 of ‘genlmsg_multicast_allns’ makes integer from pointer…
user4122787
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1 answer
Is Multicast broken for Android 2.0.1 (currently on the DROID) or am I missing something?
This code works perfectly in Ubuntu, Windows, and Mac OS X. It also works fine with a Nexus One running Android 2.1.1.
I start sending and listening multicast datagrams, and all the computers and the Nexus One will see each other perfectly. Then I…
Gubatron
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4 answers
join igmp_group not working in lightwight IP (lwip)
I'm new to lwip, and I want to create a multicast receiver with lwip. My steps are as follow:
1. Enable LWIP_IGMP;
2. Set NETIF_FLAG_IGMP in low_level_init();
3. Join multicast group, create and bind pcb;
4. udp_connect to remote_ip (or multicast IP…
user3567175
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IPv6 multicast addresses: Is the Group ID field effectively 112 bits or 32 bits?
I'm trying to understand the rules for choosing an IPv6 multicast address Group ID, and the RFC seems somewhat inconsistent. For example, in RFC 2373 section 2.7 this diagram is shown:
| 8 | 4 | 4 | 112 bits …
Jeremy Friesner
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Does Android's RTP library support multicast?
I am trying to multicast an audio stream from one device to many others using Android's RTP classes.
I do not want to use any third party libraries if at all possible.
I am able to stream two way audio between two devices using AudioStream and…
Nova Entropy
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3 answers
Writing a reliable, totally-ordered multicast system in Python
I have to write a reliable, totally-ordered multicast system from scratch in Python. I can't use any external libraries. I'm allowed to use a central sequencer.
There seems to be two immediate approaches:
write an efficient system, attaching a…
Daniel Schierbeck
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4 answers
SSIS : Using multicast to enter data into 2 RELATED destinations
I am new to SSIS. I have data coming from a single source. I need to enter that data into several tables (these tables are related by foreign key relationships). I am using multicast to enter the data into several destinations.
My question…
dcinadr
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