Infrastructure Technology  «Prev  Next»

Lesson 6 Internet multicasting
Objective Describe Internet multicasting.

Internet Multicasting: A Comprehensive Overview for E-commerce

In the realm of digital communication, Internet multicasting stands as a pivotal technique, especially germane to e-commerce platforms aiming for efficient data dissemination. Defined technically, Internet multicasting refers to the transmission of a single data packet to a specific group of recipients across a network. Unlike broadcasting, which transmits data to all nodes on a network, or unicasting, which targets a singular recipient, multicasting operates on a selective broadcast paradigm. It ensures that data reaches only those subscribers or nodes that have explicitly expressed interest in it.
Within the e-commerce context, Internet multicasting can be instrumental. Consider scenarios where live product launches, real-time auctions, or virtual trade fairs are being conducted. Instead of inundating the entire user base with data streams, multicasting allows e-commerce platforms to transmit information only to those users who have opted into the event, thereby optimizing bandwidth usage and ensuring a seamless user experience.
Key features of Internet multicasting include:
  1. Group Communication: Multicasting leverages 'multicast groups.' When a user or node wishes to receive content, they join a specific multicast group. Data is then sent to this group's address, ensuring only members receive the content.
  2. Efficiency: By transmitting a single data packet to multiple recipients simultaneously, multicasting reduces network traffic and conserves bandwidth, pivotal for e-commerce platforms handling large user bases.
  3. Dynamic Membership: Multicast groups are dynamic. Nodes can join or leave groups based on their interest, ensuring flexibility and user autonomy.
  4. Application in E-commerce: Beyond live events, multicasting can facilitate targeted marketing campaigns, real-time analytics dissemination, and synchronous updates to distributed e-commerce databases.

In summation, Internet multicasting offers a sophisticated mechanism for targeted data transmission, aligning well with the demands of contemporary e-commerce ecosystems. Its judicious implementation can lead to enhanced user experiences, efficient network utilization, and the streamlined operation of e-commerce platforms.
Internet multicasting is an IP-based networking technique used to broadcast various media types from a single source to multiple end-points. Unlike the classic peer-to-peer internetworking which consumes large amounts of bandwidth, multicasting makes efficient use of bandwidth because it implements a mainly asynchronous, one-to-many networking model, as illustrated here.

This illustrates how multicasting works.
1. Multicast in hosts, 2. Link-level Multicast, 3. Host-to router protocol, 4. Intra-domain Multicast Routing, 5. Inter-domain Multicast Routing

IP Multicast Applications

  1. Unicast is point-to-point
  2. But many applications relays the same information to many.
  3. Examples:Radio, TV, Conferencing, Distribution of control information, Distributed games
  4. But in fact, few use native multicasting today, except control and IPTV

IP Multicast Summary
  1. The Internet abstraction of hardware multicasting.
  2. Prime architect: Steve Deering
  3. Group addresses (class D)
  4. Exploits multicast-capable networking hardware if available
  5. Best-effort delivery semantics (unreliable)
  6. Receiver-based multicast: Senders send to any group, Receivers join groups
  7. Dynamic group membership: . Hosts leave and join groups dynamically
  8. Notation:
    . (S, G) . specific sender S to group G
    . (*, G) . all senders to group G	

Reliable Multicast

  1. There is no multicast-TCP.
    There is no such thing as multicast-TCP in the standard TCP/IP protocol suite. TCP is a connection-oriented, reliable transport protocol that is designed for one-to-one communication. Multicast is a one-to-many communication paradigm, where a single sender can send data to multiple receivers simultaneously.
  2. Problem: how to deal with all acknowledgments: TCP-like ACKs would cause ACK-implosions
  3. Ideas:
    1. Acknowledgment aggregation points to keep copies of data for retransmission cases
    2. Use NACKs (Negative acknowledgements)
    3. Send redundant information so that lost information can be recomputed from the information received, i.e. use forward error correcting codes (FEC)
  4. There is no general-purpose reliable multicast protocol for the Internet: Only application-specific
Multicasting supports video streaming, radio simulation, and Webcasts. Teleconferencing and videoconferencing also use multicasting, but they require more robust protocols and wider bandwidth.

IP Multicasting

Internet protocol (IP) multicasting is a variation on network multicasting. Unlike traditional Internet traffic that requires separate connections for each source-destination pair, IP multicasting allows many recipients to share the same source. This means that just one set of data packets is transmitted for all the destinations. Thus for large amounts of data, IP multicasting is more efficient than normal Internet transmissions because the server can broadcast a message to many recipients simultaneously. Standards are being developed to support multicasting over a TCP/IP network such as the Internet. These standards will allow users to join multicast groups easily.
There are several vendors of multicasting servers. Consider your needs carefully and compare their offerings before deciding on any one product.

Vendors of Multicasting Servers and Their Websites

Internet multicasting is a method used to send Internet Protocol (IP) datagrams to a group of interested receivers in a single transmission. It's an efficient way to transmit data, especially for applications like streaming media. Here's a list of some prominent vendors in the multicasting server domain:
  1. Cisco Systems, Inc.:
    • Description: Cisco is a global leader in networking and IT solutions, offering a range of products and services, including those related to multicasting.
    • Website:
  2. Juniper Networks:
    • Description: Juniper Networks specializes in network solutions and has products that support multicasting, such as their routers and switches.
    • Website:
  3. Microsoft Corporation:
    • Description: Microsoft's Windows Server has components that support multicasting, especially useful in deploying applications across networks.
    • Website:
  4. Wowza Media Systems:
    • Description: Wowza offers streaming media server software that supports multicast streaming in enterprise environments.
    • Website:
  5. Vidyo, Inc.:
    • Description: Vidyo offers video conferencing solutions that utilize multicasting for efficient video distribution.
    • Website:
  6. Zebra Technologies:
    • Description: Zebra offers the Zebra Multicast Server, which facilitates efficient data distribution across networks.
    • Website:
  7. Peplink:
    • Description: Peplink provides networking solutions, including routers and switches, some of which support multicasting functionalities.
    • Website:
  8. NewTek, Inc.:
    • Description: NewTek specializes in video production tools, and their NDI (Network Device Interface) technology leverages multicasting for video transmission.
    • Website:

These vendors are at the forefront of providing multicasting solutions, each with its unique offerings. When selecting a multicasting server, it's essential to consider the specific needs and scale of your project, and consult directly with vendors or their local representatives for detailed product specifications and capabilities.

The next lesson wraps up the module.
Ad Multicasting on the Internet