STC has created a new tailored solutions service to provide customers with the quick-start engineering and integration support needed for deploying e-services. The new service draws upon the expertise of 1,400 engineers across STC to assure customers the best possible solutions to meet their specific business needs as well as complete implementation services to ensure solutions work [...]
Try the following experiment. Run mping against a single mping receiver on the same LAN, and examine the average time. Then add a handful of roping receivers on the same LAN and repeat the experiment (if necessary, receivers can be added on a single host). Continue adding roping receivers and see how the average time [...]
Most modern host machines with low-end Ethernet cards are fully capable of sending packets fast enough to saturate a 10-Mbps link. Since multicast is built on top of UDP, preventing network flooding is entirely up to the design skill and restraint of the application programmer. This means that the sending program should rate limit the [...]
In several articles I have referred to how to select a multicast address. From the length of the various sections, it should be obvious that choosing a multicast address is not always straightforward. Selecting a multicast address is straightforward if the application being developed is for use by only a few people. Examples of these [...]
Administrative scoping was created in response to the weaknesses of TTL scoping, specifically overloading a function of the IP header to limit delivery of packets and provide privacy. Also, in dense mode protocols, expiring packets could interfere with the prune process. Instead of overloading the TTL to control the scope of a multicast group, the [...]
The need for and use of Time-To-Live or simply TTL scoping was largely motivated by the kinds of multicast routing protocols that were first developed. These protocols were based on broadcasting data to the entire network and then having uninterested receivers prune their links from the tree. The two most common of these protocols were [...]
In the main part of this book, we have tried to avoid too many details of how multicast routing works inside the network, but it is useful to see a brief explanation of how SSM makes multicast routing easier. With ASM, multicast trees that span networks are centered on well-known routers, called rendezvous points (RPs). [...]
Adding Multicast Membership Once the bind is complete, a multicast-specific call needs to be performed in order to begin receiving multicast packets. We mentioned earlier that multicast addresses are often referred to as a multicast group. In order to receive packets for a specific multicast group, a host needs to announce its intention to add [...]
The approach in this article is to build out the API and its options through the dis- cussion of simple examplesmmulticast sender and receiver programs. Sockets are an application programming interface (API) that provide basic function calls to send data across a network. Originally developed as part of the Berkeley Standard Distribution (BSD) of Unix, [...]
The history of multicast has been an evolution consisting of many changes. Though it is beyond the scope of this book to go into much detail, we will discuss briefly how multicast operates. The first deployment of multicast occurred in 1992. The motivation was to transmit audio and video from the March Internet Engineering Task [...]
