The Metropolitan ISP
The objective of this network design was to provide services for up to 100,000 people using very high-grade components that would withstand difficult environments, such as is found in Africa, to provide five or more years of reliable performance so that the new ISP would be well established with a solid reputation for service.
Most often we would consult with the client on their needs and provide documentation of the network and server designs, with which clients could build the network using their personnel. On one occasion my company was contracted to build and install the entire network as well as to provide training.
Past designs of Metropolitan networks have featured:
16 or 18 servers in 42U racks
Xeon and Opteron processors
Fastest and maximum RAM in each server
Hardware RAID for the optimal combination of speed, capacity, reliability, and ease of maintenance
On-hand cold spares for all critical components
Redundant power supplies
Operation guides for each server