Description and Information

The University's communication networks are managed by BGSU Information Technology Services (ITS) and provide access to all on-campus services, the Internet, and Internet2. Keeping in mind the ITS goal of providing and maintaining consistent service to the University community, a traffic/packet shaping system has been implemented.

A traffic/packet shaping system allocates portions of the full capacity off-campus connection to classes of traffic in order to optimize network performance. The system does not examine the data itself for content, but rather it determines the communication application being used. Application examples include e-mail transport (SMTP), file transfer (FTP), Web/hypertext (http/https), etc. The level of network allocation used by each application is based on rules defined by ITS in conjunction with other campus departments.


Figure A:


A helpful analogy is to consider a multi-lane highway and truck traffic. The highway represents the Internet link. If the trucks are color-coded to signify the cargo onboard, then they would be analogous to the data packets displaying an application. Without examining the cargo itself, traffic rules could limit certain color trucks to a defined number of lanes of the highway. Some trucks could use any lane, while perhaps blue trucks could use only two of the lanes.

Certain communication applications are designed to use as much network allocation as the physical link can provide. If use of these applications increase, then the link will become saturated by demand and service will degrade for all communications over that link. The packet shaper allows ITS to configure the maximum amount of network traffic that can be consumed by these high-demand network applications, thereby limiting the effect of increased demand on service to the community. Conversely, ITS may choose to reserve portions of the link capacity to ensure that certain applications receive at least a minimum level of service. This balancing is carried out regularly by ITS as we monitor overall use of the University network.

To extend the highway analogy, perhaps red trucks are entering the highway very frequently - perhaps to the point that they would fill all the lanes if they were allowed to do so. A traffic rule limiting red trucks to three lanes of the highway would preserve capacity for trucks of other colors. Of course, the red trucks would experience congestion. And if green trucks were known to require special treatment (perhaps they carry perishable cargo), then a rule that reserved a lane for the exclusive use of green trucks might be appropriate.

Over time, ITS will continue to tune the packet shaper in response to changes in the behavior of the community, in response to the introduction of new applications, and based upon observed changes in congestion on Internet links. In our analogy, this would correspond to noticing patterns in truck colors, noticing new truck colors, or noticing the frequency of traffic jams.