Zen and the Art of Internet by Brendan P. Kehoe (easy books to read in english .txt) 📕

free. Commercial Services for applications that are commercially available over the Internet.

Usenet is often used to announce a new service or capability on the Internet. In particular, the groups comp.archives and comp.protocols.tcp-ip are good places to look. Information will drift into other areas as word spreads. Usenet News for information on reading news.

Finger

On many systems there exists the finger command, which yield information about each user that's currently logged in. This command also has extensions for use over the Internet, as well. Under normal circumstances, the command is simply finger for a summary of who's logged into the local system, or finger username for specific information about a user. It's also possible to go one step further and go onto the network. The general usage is

finger @hostname

To see who's currently logged in at Widener University, for instance, use

% finger @cs.widener.edu [cs.widener.edu] Login Name TTY Idle When Where brendan Brendan Kehoe p0 Fri 02:14 tattoo.cs.widene sven Sven Heinicke p1 Fri 04:16 xyplex3.cs.widen

To find out about a certain user, they can be fingered specifically (and need not be logged in):

% finger [email protected] [cs.widener.edu] Login name: bart In real life: Bart Simpson Directory: /home/springfield/bart Shell: /bin/underachiever Affiliation: Brother of Lisa Home System: channel29.fox.org Last login Thu May 23 12:14 (EDT) on ttyp6 from channel29.fox.org. No unread mail Project: To become a "fluff" cartoon character. Plan: Don't have a cow, man.

Please realize that some sites are very security conscious, and need to restrict the information about their systems and users available to the outside world. To that end, they often block finger requests from outside sites---so don't be surprised if fingering a computer or a user returns with Connection refused.

Internet Relay Chat

The Lamont View Server System On lamont.ldgo.columbia.edu in pub/gb.tar.Z.

Ping

The ping command allows the user to check if another system is currently ``up'' and running. The general form of the command is ping system. {The usage will, again, vary.} For example,

ping cs.widener.edu

will tell you if the main machine in Widener University's Computer Science lab is currently online (we certainly hope so!).

Many implementations of ping also include an option to let you see how fast a link is running (to give you some idea of the load on the network). For example:

% ping -s cs.swarthmore.edu PING cs.swarthmore.edu: 56 data bytes 64 bytes from 130.58.68.1: icmp_seq=0 ttl=251 time=66 ms 64 bytes from 130.58.68.1: icmp_seq=1 ttl=251 time=45 ms 64 bytes from 130.58.68.1: icmp_seq=2 ttl=251 time=46 ms ^C --- cs.swarthmore.edu ping statistics --- 3 packets transmitted, 3 packets received, 0% packet loss round-trip min/avg/max = 45/52/66 ms

This case tells us that for cs.swarthmore.edu it takes about 46 milliseconds for a packet to go from Widener to Swarthmore College and back again. It also gives the average and worst-case speeds, and any packet loss that may have occurred (e.g. because of network congestion).

While ping generally doesn't hurt network performance, you shouldn't use it too often---usually once or twice will leave you relatively sure of the other system's state.

Talk

Sometimes email is clumsy and difficult to manage when one really needs to have an interactive conversation. The Internet provides for that as well, in the form of talk. Two users can literally see each other type across thousands of miles.

To talk with Bart Simpson at Widener, one would type

talk bart@@cs.widener.edu

which would cause a message similar to the following to be displayed on Bart's terminal:

Message from [email protected] at 21:45 ... talk: connection requested by [email protected] talk: respond with: talk [email protected]

Bart would, presumably, respond by typing talk [email protected]. They could then chat about whatever they wished, with instantaneous response time, rather than the write-and-wait style of email. To leave talk, on many systems one would type Ctrl-C (hold down the Control key and press C). Check local documentation to be sure.

There are two different versions of talk in common use today. The first, dubbed old talk,'' is supported by a set of Unix systems (most notably, those currently sold by Sun). The second, ntalk (akanew talk''), is more of the standard. If, when attempting to talk with another user, it responds with an error about protocol families, odds are the incompatibilities between versions of talk is the culprit. It's up to the system administrators of sites which use the old talk to install ntalk for their users.

Wide Area Information Servers (WAIS)

The WHOIS Database

The main WHOIS database is run at the Network Information Center (NIC). The whois command will let you search a database of every registered domain (e.g. mit.edu) and of registered users. It's primarily used by system postmasters or listowners to find the Points of Contact for a site, to let them know of a problem or contact them for one reason or another. You can also find out their postal address. For example:

% whois mit.edu Massachusetts Institute of Technology (MIT) MIT.EDU 18.72.2.1 Massachusetts Institute of Technology (MIT-DOM) MIT.EDU

Note that there are two entries for mit.edu; we'll go for the second.

% whois mit-dom Massachusetts Institute of Technology (MIT-DOM) Cambridge, MA 02139

Domain Name: MIT.EDU

Administrative Contact, Technical Contact, Zone Contact: Schiller, Jeffrey I. (JIS) [email protected]

(617) 253-8400

Record last updated on 22-Jun-88.

Domain servers in listed order: STRAWB.MIT.EDU 18.71.0.151 W20NS.MIT.EDU 18.70.0.160 BITSY.MIT.EDU 18.72.0.3 LITHIUM.LCS.MIT.EDU 18.26.0.121

To see this host record with registered users, repeat the command with a star ('*') before the name; or, use '%' to show JUST the registered users.

Much better! Now this information (sought, possibly, by a system administrator) can be used to find out how to notify MIT of a security issue or problem with connectivity.

Queries can be made for individuals as well; the following would yield an entry for the author:

% whois brendan Kehoe, Brendan (BK59) [email protected] Widener University Department of Computer Science Kirkbride 219 P.O. Box 83 Widener University Chester, PA 19013

(215)/499-4011

Record last updated on 02-May-91.

Included is the author's name, his handle (a unique sequence of letters and numbers), information on how to contact him, and the last time the record was modified in any way.

Anyone can register with the whois database. People who are administrative or technical contacts for domains are registered automatically when their domain applications are processed. For normal users, one must simply fill out a form from the NIC. FTP to nic.ddn.mil and get the file netinfo/user-template.txt. The completed form should be mailed to [email protected].

Other Uses of WHOIS

Also, many educational sites run WHOIS servers of their own, to offer information about people who may be currently on the staff or attending the institution. To specify a WHOIS server, many implementations include some sort of option or qualifier---in VMS under MultiNet, it's /HOST, in Unix -h. To receive information about using the Stanford server, one might use the command

whois -h stanford.edu help

A large list of systems offering WHOIS services is being maintained by Matt Power of MIT ([email protected]). It is available via anonymous FTP from sipb.mit.edu, in the directory pub/whois. The file is named whois-servers.list.

The systems available include, but are certainly not limited to, Syracuse University (syr.edu), New York University (acfcluster.nyu.edu), the University of California at San Diego (ucsd.edu), and Stanford University (stanford.edu).

``Fingers were made before forks.'' Jonathan Swift, Polite Conversation

Commercial Services

Many services can be accessed through the Internet. As time progresses and more outlets for commercial activity appear, once-restricted traffic (by the NSFnet Acceptable Use Policy) may now flow freely. Now that there are other networks for that information to travel on, businesses are making their move.

Internet Service Providers

Providers (AlterNet, PSI, etc)...

Supercomputers The Internet Resource Guide (IRG) contains a chapter on computer time that's available for a fee. Rather than reproduce it here, which would fast become out-of-date as well as triple the size of this guide, it's suggested that the reader consult the IRG if such services are of interest.

Electronic Journals

The Association of Research Libraries (ARL) publishes a hard-copy directory of electronic journals, newsletters, and scholarly discussion lists. It is a compilation of entries for hundreds of

sts, dozens of journals and newsletters, and a many ``other'' titles, including newsletter-digests, into one reference source. Each entry includes instructions on how to access the referenced publication or list.

The documents are available electronically by sending the commands

get ejournl1 directry get ejournl2 directry

to the server at [email protected]. Listservs for further instructions on using a listserv.

The directory, along with a compilation by Diane Kovacs called Directories of Academic E-Mail Conferences, is available in print and on diskette (DOS WordPerfect and MacWord) from:

Office of Scientific & Academic Publishing Association of Research Libraries 1527 New Hampshire Avenue, NW Washington, DC 20036 [email protected]

(202) 232--2466

(202) 462--7849 (Fax)

The ARL is a not-for-profit organization representing over one hundred research libraries in the United States and Canada. The publication is available to ARL members for $10 and to non-members for $20 (add $5 postage per directory for foreign addresses). Orders of six or more copies will receive a 10% discount; all orders must be prepaid and sent to the ARL.

Commercial Databases

The American Institute of Physics maintains the Physics Information Network. It contains the bibliographic SPIN and General Physics Advanced Abstracts databases. Also available is access to bulletin boards and several searchable lists (job notices, announcements, etc). Telnet to pinet.aip.org; new users must log in as NEW and give registration information.

Some of the databases accessible through WAIS (WAIS) are available for a fee.

Clarinet News

Clarinet's an electronic publishing network service that provides professional news and information, including live UPI wireservice news, in the Usenet file format.

Clarinet lets you read an ``electronic newspaper'' right on the local system; you can get timely industry news, technology related wirestories, syndicated columns and features, financial information, stock quotes and more.

Clarinet's provided by using the Usenet message interchange format, and is available via UUCP and other delivery protocols, including NNTP.

The main feature is ClariNews, an ``electronic newspaper,'' gathered live from the wire services of United Press International (UPI). ClariNews articles are distributed in 100 newsgroups based on their subject matter, and are keyworded for additional topics and the geographical location of the story. ClariNews includes headlines, industry news, box scores, network TV schedules, and more. The main products of ClariNews are:

ClariNews General, the general news``paper'' with news, sports, and features, averaging about 400 stories per day.

TechWire, special groups for stories on science, technology, and industry stories around them.

ClariNews-Biz, business and financial stories.

Newsbytes, a daily computer