Point-to-Point Private Circuits
What is a Point-to-Point Private Circuit?
(also known as a point to point leased line)
This is a connection running from a company's premises to another location (across a metropolitan area, another city or country etc.) The ISP or carrier would determine the route over its network; configure the line (often physically laying down some or all of the cable required to get from point A to point B) and determine its price. Depending on whether a third party is used for the backhaul between sites, either the full capacity of the tail circuit is available to the customer or perhaps a rate limited proportion only.
Note that point-to-point leased lines can have dedicated internet access at one or both ends of the line and can distribute / route bandwidth to the other end. Dedicated point-to-point lines originally formed the infrastructure of private networks.
The difference between SDH and Ethernet
In brief, these standards are the basis for fibre optic data transmission and do not interoperate at bit level currently. (SONET is the standard for the US and Canada). SDH bandwidth speeds are available in 2 Mbps, 34 Mbps, 45 Mbps 155 Mbps and 622 Mbps whereas Ethernet is available in 10 Mbps, 100 Mbps, 1 Gbps and 10 Gbps.
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