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Policy on Computer Disconnection from PennNet

Background: A well functioning network is critical to the research, academic and service missions of the University. Information Security has documented an increasing frequency of computer intrusions which threaten the integrity of PennNet. The capacity of entire departments to teach and conduct research has been limited as a result, and sensitive data have been at risk of unauthorized disclosure. At times, rapid response is required to protect the integrity of systems, data and those that rely on them. Inefficiency sometimes results because the owners of the penetrated machines can not be located. Disagreements arise over the magnitude and immediacy of the problems without a formal mechanism for resolving conflicts.

Certain types of misconfiguration of Penn systems, intentional or otherwise, can have serious and detrimental consequences. Examples include using another host's Internet Protocol address ("IP Spoofing") or misconfigured networking protocols. Normal operation of Penn computers, and even computers elsewhere on the worldwide Internet, can be compromised. Networks can become so congested that network traffic can not get through.

Purpose: The goal of this policy is to protect the academic missions served by Penn's computers and networks from disruption.

Policy: Information Systems and Computing (ISC) will disconnect from PennNet any computers that have actually damaged or pose an imminent threat of harming the integrity of PennNet.

Scope: This policy only applies to computers and devices attached directly or indirectly to PennNet, including improper or defective "daisy-chain" connections and private Local Area Networks with active networking components connected to PennNet wallplates and hosts.

This policy does not address removing computers from PennNet for reasons related solely to their content.

Implementation: Systems administrators must report serious computer security incidents to the University Information Security Officer. Serious computer security incidents will be defined as those that jeopardize the integrity, privacy and/or availability of other computers and networks. Examples of serious computer security incidents include break-ins where privileged accounts (e.g. UNIX "root" account, or NT "Administrator" account) are used without authorization, incidents where network traffic is monitored without authorization, and incidents where Penn computers or networks are either the source or the target of "denial of service" attacks. The Information Security Officer will coordinate the response to computer security incidents, including notifying campus systems administrators, law enforcement officers, external sites, incident response teams and University offices as appropriate.

Authorized actions: If, in the judgment of the Vice Provost for ISC (VPISC) or his/her designate, criteria are met which suggest that a system poses a significant and immediate threat either to:

The security of other Penn computers and networks, or

The continued operation of Penn networks and computers,

and the problem cannot be resolved expeditiously through collaboration between the computer owners and ISC, then ISC will notify senior management of the department or unit and will require the owners to remove the computer from the network until the problem is solved.

Absent/Unidentified Owners: If ISC is unable, using the Assignments database, to identify a system owner or Local Support Provider (LSP), ISC will move unilaterally to protect the network by disconnecting the threatening system.

Disputes: In cases where there is persistent disagreement between ISC and the owner of the perceived threat, ISC must notify the owner and the LSP of the following information in writing:

The reason for the disconnection

What steps must be taken for the network connection to be restore

How to arrange for the system to be reconnected

The process of appealing a decision to disconnect

When the owner of the system has taken the steps necessary to correct the problem, ISC will restore the PennNet connection as soon as possible.

Appealing a Decision to Disconnect: The Council Committee on Communications shall appoint a subcommittee to review appeals of decisions to disconnect computers. The subcommittee will consist of:

At least four members of the faculty appointed by the Committee on Communications, one of whom to serve as chair .

VPISC or her/his designate

University Information Security Officer or her/his designate

The Committee on Communications may designate alternates to serve on the hearings of an appeal when its appointees are unavailable.

The owner of a disconnected system who believes that the threat that the system posed is outweighed by the impact of its disconnection on their academic mission may appeal the decision by documenting this belief in writing to the chair of the subcommittee. The chair or her/his designate may resolve the dispute amicably; failing this it will be heard formally by the subcommittee. The subcommittee will resolve conflicts as rapidly as possible within the constraints of fairness. It will establish and follow its own operating procedures.

If the subcommittee does not begin the proceedings within 5 working days in cases where the issue is a threat and not actual harm, or 30 working days in cases where ISC can document actual harm, the subject system must be reconnected. Once the subcommittee has begun the process, time limits will not be imposed.

In considering appeals, the subcommittee will balance the value of leaving machines connected against the associated risks. Its decision will be final. The only recourse for faculty whose appeals are denied will be to the Senate Committee on Academic Freedom and Responsibility. ISC may not appeal. However, it may re-disconnect the computer and restart the entire process whenever another trigger event is detected.

System owners who believe that their freedom of expression has been unduly infringed may, under the Guidelines for Open Expression, request that the Committee on Open Expression determine if the Guidelines were properly interpreted and applied to the disconnection of their system.

Interpreting this policy: As technology evolves, questions may arise about how to interpret this policy. The VPISC may as needed, after consultation with the Council Committee on Communications, publish specific rules interpreting this policy.

Advice: To minimize the likelihood of a serious computer security compromise, campus systems administrators are encouraged to configure their systems in accordance with the following standards:


Assignments Database: A computer database provided by ISC Networking where Local Support Providers maintain information about PennNet connected computers, including the network address, operating system, and contact information. For more information about how to maintain records in the Assignments Database, contact:

Denial of Service Attack: An attack where someone takes up so much of a shared resource that insufficient is left for others. Denial of service attacks threaten the availability of resources, including computer processes, disk space, or network capacity among other things. The result is a degradation or loss of service.

Local Support Provider: Departments/Units at Penn appoint Local Support Providers to provide information technology support locally.


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