May 14th, 2004 by Dana Roode
Unsolicited, unwelcome, and sometimes offensive commercial email — “spam” — continues to plague the world’s electronic mail users. Here at UCI, NACS began regularly filtering inbound electronic mail nearly two years ago in an effort to catch and label spam, rendering it easily identifiable by end users. NACS runs the SpamAssassin software on the campus electronic mail gateways (also known as Mail Transfer Agents, or MTAs), as well as on the Enterprise Services servers often referred to as “ea” and “e4e”.
SpamAssassin uses a variety of techniques to determine if a message is spam, and if it is, the software adds “headers” to the message labeling it as such. Most electronic mail programs, such as Eudora, Outlook, and Netscape, are capable of reading and processing these special headers. You must configure your mail software to take advantage of this feature.
NACS remains dedicated to reducing the amount of spam received by our users, and we continue to research new ideas and techniques for doing so.
If you are uncertain as to whether or not your electronic mail program can be configured to make use of the SpamAssassin headers, contact your local computing support coordinator or the NACS Response Center.
More information about the NACS spam tagging service can be found on the web at http://www.nacs.uci.edu/email/spam/index.html, including how to configure Eudora, Netscape, Outlook XP, Mail for MacOS X, Microsoft Entourage X, and Procmail to filter-out spam which has been identified the the service.
May 14th, 2004 by Dana Roode
NACS hosts and manages the Middle Performance Computing (MPC) “Beowulf” Cluster on behalf of campus researchers who need substantial computational power.
MPC comprises private nodes and shared nodes, including a part-time shared cluster using NACS PC lab systems. MPC systems feature a mix of architectures to provide high computational throughput.
A feature of the MPC service is the opportunity for researchers to join their own systems to the cluster. In exchange for system administration, housing, and 24/7 oversight provided by NACS, researchers allow 25% of their systems to be configured as part of a campus computational resource. (The remaining 75% is configured to be a cluster, or “queue”, dedicated to the owner.) Contributors may, of course, make use of systems designated for campus use.
Contributors also become voting members of the MPC Advisory Board. The purpose of the MPCAB is to advise NACS on the governance, policies, procedures, and technical aspects of the MPC cluster.
Researchers may request accounts on MPC (and other NACS resources) online. Any future changes that impact MPC users will be posted on the MPC website.
NACS also hosts the GradEA Beowulf Cluster for the exclusive use of UCI graduate students.
MPC web site:
http://www.nacs.uci.edu/computing/mpc/
MPC account requests:
http://www.nacs.uci.edu/rcs/resources.html
GradEA web site:
http://www.nacs.uci.edu/computing/gradea/
May 14th, 2004 by Dana Roode
Many faculty and staff have a need to access UCInet and other network resources from off campus, in particular, scholarly resources licensed by the UCI Libraries and available only to systems which are part of UCInet.
NACS has developed and supports three different ways of connecting to UCInet from off campus:
- the lifeline modem pool
- the proxy server
- the virtual private network (VPN) device.
Modem Pool
The first such service deployed was the “lifeline modem pool.” This is, as the name implies, the resource of last resort. Bandwidth (data throughput) is limited, compared to cable modem or DSL, and there are limits on the amount of time you are allowed to use the service. The advantage is that it can be used from any telephone line in the world (if you are willing to accept long-distance charges).
Proxy Server
The proxy server is a collaborative effort between NACS and the UCI Libraries. Users of the proxy server make web requests as if from on campus, regardless of how they connect to the Internet. However, this service is sometimes slow depending on the number of users simultaneously working through it.
VPN
An alternative to using the proxy server is to use the NACS Virtual Private Network, or “VPN”.
The advantage that the VPN has over the proxy server is that it opens up ALL network resources that require a UCI network address, while the proxy server only addresses Web-based applications. It may also be faster. Finally, the VPN offers a secure connection to campus from outside, commercial, and wireless networks, which are inherently insecure.
It is expected that proxy server and lifeline modem pool users will migrate to the VPN as the preferred way of connecting with campus services which are restricted to UCI address space.
Because the proxy server requires manually encoding each site which is restricted to UCI affiliates, it is difficult to maintain, and it is intended that this service be phased out over the next year.
For more information, please consult the following web pages.
Lifeline modem pool: http://www.nacs.uci.edu/network/modem/
NACS Proxy Server: http://www.nacs.uci.edu/network/proxy/
NACS VPN Information: http://www.nacs.uci.edu/security/vpn.html