BGP/MPLS IP VPNs: Better Than ATM/Frame Relay

摘要

Enterprise customers spend considerably more on private line, public frame relay and public ATM services than on public IP networks. This is likely to change over the next few years, because ATM/FR is no longer as attractive to either enterprises or providers.Part of the problem with ATM/FR services is price, which is unnecessarily high because of low levels of competition and limited availability, compared to globally-available ISP services. But both FR and ATM face other challenges as well.FR networks have been popular for remote office links, many of which still carry SNA applications running at only 56 kbps. This worked fine for distributed transaction processing, where traffic volumes are small.