scordella
Feb 20, 2011, 03:49 PM
Consider the following applications. In each case indicate whether you would use X.25, frame relay, or ATM facilities. Assume that the facilities are available and “competitively ”priced.
You have a large number of locations in a metropolitan area. At each location there is a large number of real-time data transactions processed. Information about the transactions must be sent independently and more or less randomly among the locations. That is, the transaction are not batched or do not occur in bunches. Performance requirements are such that the delay must be short. Volumes at each location are modest but in total range up to few megabits per second in total.
You now have a national WAN with about a half dozen locations in relatively remote areas. The transmission facilities are varied and include radio links, satellite links, and phone links using modems. The data rates are relatively modest.
In this case, you have multimedia applications. These include image communication and significant real-time video and audio services. These are interspersed with a multitude of other data services. The number of locations is small, but with the image and video applications the volume is quite large, nearing gigabit per second ranges. There are also a large number of users and applications involved so that a large number of virtual circuits are needed even though the number of locations is small.
You have a large number of locations in a metropolitan area. At each location there is a large number of real-time data transactions processed. Information about the transactions must be sent independently and more or less randomly among the locations. That is, the transaction are not batched or do not occur in bunches. Performance requirements are such that the delay must be short. Volumes at each location are modest but in total range up to few megabits per second in total.
You now have a national WAN with about a half dozen locations in relatively remote areas. The transmission facilities are varied and include radio links, satellite links, and phone links using modems. The data rates are relatively modest.
In this case, you have multimedia applications. These include image communication and significant real-time video and audio services. These are interspersed with a multitude of other data services. The number of locations is small, but with the image and video applications the volume is quite large, nearing gigabit per second ranges. There are also a large number of users and applications involved so that a large number of virtual circuits are needed even though the number of locations is small.