Which OSPF metric would result from a bandwidth reference of 10,000,000,000 on a 1-Gbps link?

In OSPF (Open Shortest Path First), the metric used to calculate the cost of a link is derived from the reference bandwidth, which is typically set to 100 Mbps by default. The cost is calculated using the formula:

Cost = Reference Bandwidth / Interface Bandwidth.

In this case, the reference bandwidth is set to 10,000,000,000 bits per second (10 Gbps), and the link speed is 1 Gbps. To find the OSPF metric (cost) for this link, you use the aforementioned formula. First, express the link speed in the same unit (10^9):

Cost = 10,000,000,000 / 1,000,000,000 = 10.

Thus, the resulting metric for a 1-Gbps interface with a reference bandwidth of 10 Gbps is indeed 10. This shows how OSPF treats higher bandwidth links as less costly, promoting the use of such paths in routing decisions. Understanding how to effectively configure and interpret these metrics is crucial for optimizing OSPF in enterprise networks.