Question : Network specifications

Hi, iam designing a network on paper and i would like the specifications for the following: Building 1 floor 1, 50 users, floor 2, 50 users, building 2, 50 users and building 3, 50 users. Buildings 1 and 3 are pre-wired with Cat 5 UTP and building 2 is grade II listed.  The connection is by LAN and each bulding runs its own applications. Any ideas?

Answer : Network specifications

Small note,

For more speed between buildings, use two or more fiber channels, the 3750 can bundle up to 4 fiber "channels", which means 4GB backbone..