Yes, there are still many companies using legacy systems that are currently operating on old Frame Relay/ATM systems.
Also, there are many reasons why a company could still be on these systems, maybe old equipment, software, etc.
Probably the most logical one is they haven't been introduced to MPLS yet. We've noticed that companies still don't know what MPLS is
As funny as it may seem, we have converted several legacy T1 and T3 circuits to Ethernet Services and the companies didn't even know what Ethernet service was until we explained it to them. After we explained it, they migrated to Ethernet. The same case studies applies to MPLS.--
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