HP 600 Series, Услуги и приложения

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A number of alternative backbone technologies are emerging in the industry.
Long-distance carriers have made the most progress in providing frame relay
services. Frame relay bases its design on packet-switching technology, as
does X.25. However, unlike X.25, frame relay provides its control through
only OSI layers 1 and 2, which preserves network performance. The design
of a frame relay network provides an fully meshed network that compen-
sates for point failures with automatic rerouting. Customers have a single
point of entry to the frame relay network, and all network routing happens
transparently. This is depicted in figure 3.
Figure 3. Frame Relay Network
Frame relay is also very suitable for bursty data networks, where irregular
traffic patterns cause variable bandwidth demands. A frame relay backbone
network would provide Fleet Call with built-in redundancy and high perform-
ance. Compared to a meshed topology with dedicated circuits, frame relay is
more cost-effective. In addition, the selected long-distance carrier assumes
total responsibility for failures within the meshed network, thereby relieving
Fleet Call of this responsibility.
Frame Relay Network Design: Fleet Call, Inc.
Network Topology
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