Multicast is the protocol which allow nodes inside to a cluster to communicate without knowing each other.<\/p>\n
You can think of multicast of a radio or a TV channel, only those who are tuned received the information.<\/p>\n
Communication between nodes is provided by JGroups, which is library for multicast communication.<\/p>\n
<\/p>\n
What is multicasting? <\/p>\n In a conventional Ethernet network, most Internet Protocol (IP) packets are sent using unicast <\/p>\n Unicast transmission sends a separate stream of data to each receiver, while multicast transmission sends <\/p>\n B. How do Multicast Addresses Work? <\/p>\n","protected":false},"excerpt":{"rendered":" Multicast is the protocol which allow nodes inside to a cluster to communicate without knowing each other.<\/p>\n You can think of multicast of a radio or a TV channel, only those who are tuned received the information.<\/p>\n Communication between nodes is provided by JGroups, which is library for multicast communication.<\/p>\n <\/p>\n What is multicasting? There […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"_links":{"self":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/1005"}],"collection":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1005"}],"version-history":[{"count":4,"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/1005\/revisions"}],"predecessor-version":[{"id":1008,"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/1005\/revisions\/1008"}],"wp:attachment":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1005"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1005"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1005"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\nThere are three types of communication between computers in a network:
\nUnicast – one computer talks directly to another computer<\/strong>
\nBroadcast – one computer talks to all computers
\nMulticast – one computer talks to a select group of others<\/strong><\/p>\n
\n(host-to-host) transmission. Every computer in a network can transmit and receive packets,
\nwhich in unicast transmission are labelled with the address of the receiving computer. Each
\ncomputer listens to all the other packets that are sent in the network and looks for packets
\nthat are addressed to itself. When a computer encounters a packet that is addressed to itself, it
\ninterrupts the processor and hands the packet to the operating system to process.
\nUnicasting is great for communicating directly with one or a few other computers. However if
\nyou want to communicate with a number of computers, unicasting becomes inefficient because
\na copy of each packet must be sent to every receiving unicast address. Unicasting uses up
\nbandwidth fast, especially when sending large multimedia files, which already take up a lot of<\/p>\n
\none stream of data that is separated as it passes through the routers and sent on to the receivers
\nWhat are the benefits of multicasting?
\nMulticasting optimises the performance of your network. Because only one multicast data stream
\nis sent out, multicasting preserves bandwidth on your network and eliminates traffic redundancy. In
\ncontrast, the unicast environment sends out a separate copy of the data to each receiver.
\nMulticasting also provides enhanced efficiency by controlling the traffic on your network and
\nreducing load on network devices.The clients on your network are able to decide whether or
\nnot to listen to a multicast address, so packets are only sent to where they are required.
\nIn addition, multicasting is scalable across different sized networks, but is particularly suited to
\nWAN environments. It gives people in different locations access to streaming data files, like a
\nvideo, film or live presentation without taking up excessive bandwidth or broadcasting the data
\nto all users on the network.<\/p>\n
\nBecause multicast addresses identify a transmission session rather than a specific physical
\ndestination or host, all of the receivers in a multicast group are identified by a single IP address.
\nThis section outlines how multicast IP and MAC addresses are structured.
\nHow are IPv4 multicast addresses organised?
\nIPv4 multicasting uses class D addresses. A class D address starts with 1110 higher order bits in
\nthe first octet, followed by a 28-bit group address.The last 28 bits of a class D address are
\nunstructured, unlike the class A, B and C IP addresses.These 28 bits identify the multicast group
\nidentity, which is a single address in the range of 224.0.0.0 to 239.255.255.255.
\nSome IPv4 multicast addresses are reserved for particular purposes.These addresses are
\nassigned by the Internet Assigned Numbers Authority (IANA).Table 1 outlines some of the
\nwell-known IPv4 multicast addresses.<\/p>\n