Our Network

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Internet Service Providers and Infrastructure

Our commodity internet bandwidth (currently 200Mbit as of April 11, 2012; to be 300Mbit within a few weeks) is purchased through Paetec, while our academic and administrative bandwidth is purchased through UMass, who buys their access from Level 3 and Qwest. Connectivity between colleges is provided by the Five College fiber-optic network, linking all five campuses in a ring with a single run out of that ring to 1 Federal Street in Springfield, much like a lollipop on a stick. If that 'stick' to Springfield should be cut, for whatever reason, UMass leases a redundant 1-gigabit link from NEON Communications, direct to Boston, that acts as a failsafe to ensure connectivity for the Five Colleges. In case of a loss of connectivity somewhere along the ring, traffic will be rerouted in the opposite direction along the ring, going the long way but still eventually reaching its destination. Each campus has a redundant connection to this ring. At Hampshire, we have one connection in the basement of Cole, and one in ASH. Failover is automatic.

Hampshire's Network

Hampshire's network is a star topology, centered in the basement of Cole. In general, buildings are connected to the core with gigabit fiber, and have a layer 3 OSPF networking device with an associated VLAN and subnet. This is to increase resiliency, keep traffic local as much as possible, and reduce the size of the broadcast domains on campus. For security and IP conservation reasons, all of these addresses are RFC1918's that get translated at the edge of our network into a /21 of globally-valid addresses. All connections made concurrently by a single IP inside our network are mapped to the same IP outside, and your translation is reserved for 30 minutes.

We have a gigabit physical connection to each of the other four institutions in the Five College Consortium, through the Five College Fiber Network. Any connection initiated from on campus to any of the other four colleges will get routed over this link, meaning we get gigabit speeds between the institutions on the Five College Network. We have firewalls at the edges of our network, one on each link, that perform firewall and NAT functions. These units are currently Cisco ASA5520's.

The bandwidth shaper on the Paetec link is a NetEqualizer NE3000. It shares bandwidth equally among IP's currently asking for it by delaying top users' packets in units of 1/1000 of a second when link utilization nears saturation. It also limits the number of concurrent connections each IP can use.

The College maintains an L2TP/IPSec VPN, which is run on a Vyatta box. Access to Hampshire College's network through the VPN is limited to faculty and staff.

The College also maintains two traditional PBXes and one Voice-over-IP PBX for telecommunications.

Wireless Networking

Hampshire's wireless network is powered by Cisco 1131 (802.11a/b/g), 1142 (a/b/g/n), and H3C 2620/2620E (a/b/g/n) Access Points at various locations around the campus, ensuring connectivity in all public areas of the campus, as well as all of Dakin and Merrill, most of Enfield and Greenwich and the renovated areas of Prescott. We are currently transitioning from "fat" Cisco access points to "thin" H3C access points. There are two discrete wireless networks available in academic areas -

  • Hampguest (public) – This network does not require a login and has an entirely separate connection to the Internet. In this way, it is like sitting in an internet cafe - you are not really on Hampshire's network while using this wireless network, and as such cannot access anything that is on-campus only, and on-campus services will be slower than when using wallace or the dorm networks. This network is only available in the public areas of campus. Students should register their guests' computers under their names if they have guests that need access in the dorms. In this way, you are taking responsiblity for the actions of your guests on our network.
  • Wallace (private) – This network requires a Hampnet login, and provides full, direct access to on-campus services.

In the dorms, the network name matches the housing area, and requires a Hampnet login, like wallace. For instance, in Merrill, the network name is "merrill".

Future Projects

  • Full 802.11n wireless coverage in Enfield and Greenwich, coverage in Prescott will continue to follow the renovations
  • 10 gigabit backbone
  • WPA2-encrypted wireless networks
  • More Open Source network equipment
  • IPv6 Deployment
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