Changes
→Network Topology
== Network Topology ==
In Blacksburg, CNS has redundant fiber uplinks from the [[Andrews Information Systems Building]] to Ashburn, Virginia and Atlanta, Georgia. The [[Mid-Atlantic Broadband Communities Corporation]] provides the dual OC-192 (10 Gigabit) connections to Ashburn, in addition to the unspecified and either OC-192 or OC-768 connections to Atlanta.
CNS's primary upstream router is routers are located in Equinix's [[Ashburn, Virginia]] datacenter. At Equinix, CNS has about 4 Gbps aggregate bandwidth for commodity Internet from Cogent, as well as, through the [[Mid Atlantic Terascale Partnership]], connections to [[Network Virginia]], [[National LambdaRail]], and [[Internet2]]. They are also a member of the [[Mid-Atlantic Research Infrastructure Alliance]], although it is unclear what role this alliance provides in providing connectivity. In 2014, CNS added additional upstream routers in Telx's [[Atlanta, Georgia]] datacenter. This additional presence location improves network redundancy and is the first located outside of Virginia.
From the Andrews Information Systems Building, there are redundant fiber connections to the main campus at both [[Burruss Hall]] and [[Cassell Colliseum]]. [[Owens Hall]], [[Hillcrest Hall]], and [[Shanks Hall]] have intermediate routers for some buildings. Nearly all ethernet portals on campus are capable of 100 Mbps or Gigabit speeds, due to fiber interconnects between buildings; however, intrabuilding wiring varies in age and may not support high speeds. The vast majority of campus IPv4s come from two directly-allocated blocks (128.173.0.0/16 and 198.82.0.0/16).