==Phrack Inc.== Volume Three, Issue 25, File 4 of 11 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= =-= =-= =-= S P A N =-= =-= =-= =-= Space Physics Analysis Network =-= =-= =-= =-= Brought To You by Knight Lightning =-= =-= =-= =-= March 15, 1989 =-= =-= =-= =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Preface ~~~~~~~ In the spirit of the Future Transcendent Saga, I continue to bring forth information about the wide area networks. The information presented in this file is based primarily on research. I do not have direct access to SPAN other than through TCP/IP links, but this file should provide you with general information with which to properly use the Space Physics Analysis Network. Introduction ~~~~~~~~~~~~ The Space Physics Analysis Network (SPAN) has rapidly evolved into a broadly based network for cooperative, interdisciplinary and correlative space and Earth science data analysis that is spaceflight mission independent. The disciplines supported by SPAN originally were Solar-Terrestrial and Interplanetary Physics. This support has been expanded to include Planetary, Astrophysics, Atmospherics, Oceans, Climate, and Earth Science. SPAN utilizes up-to-date hardware and software for computer-to-computer communications allowing binary file transfer, mail, and remote log-on capability to over 1200 space and Earth science computer systems in the United States, Europe, and Canada. SPAN has been reconfigured to take maximum advantage of NASA's Program Support Communication Network (PSCN) high speed backbone highway that has been established between its field centers. In addition to the computer-to-computer communications which utilizes DECnet, SPAN provides gateways to the NASA Packet Switched System (NPSS), GTE/Telenet, JANET, ARPANET, BITNET and CSNET. A major extension for SPAN using the TCP/IP suite of protocols has also been developed. This file provides basic information on SPAN, it's history, architecture, and present guidelines for it's use. It is anticipated that SPAN will continue to grow very rapidly over the next few years. Several existing wide-area DECnet networks have joined with SPAN to provide a uniform internetwork structure and more will follow. History Of The SPAN and the Data Systems Users Working Group (DSUWG) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ A considerable evolution has occurred in the past two decades in the way scientific research in all disciplines is done. This is particularly true of NASA where early research was centered around exploratory missions in which measurements from individual scientific instruments could be meaningfully employed to advance the state of knowledge. As these scientific disciplines have progressed, a much more profound and interrelated set of questions is being posed by researchers. The result is that present-day investigations are generally much more complex. For example, within the space science community large volumes of data are acquired from multiple sensors on individual spacecraft or ground-based systems and, quite often, data are needed from many institutions scattered across the country in order to address particular physical problems. It is clear that scientific research during the late 1980s and beyond will be devoted to intense multi-disciplinary studies aimed at exploring very complex physical questions. In general, the need for researchers to exchange data and technical information in a timely and interactive way has been increasing. The problems of data exchange are exacerbated by the lack of standards for scientific data bases. The net result is that, at present, most researchers recognize the value of multi-disciplinary studies, but the cost in time and effort is devastating to their research efforts. This trend is antithetical to the needs of the NASA research community. SPAN is only one of many research networks that are just beginning to fill a need for access to remote capabilities that are not obtainable locally. In May of 1980 the Space Plasma Physics Branch of the Office of Space Science of NASA Headquarters funded a project at Marshall Space Flight Center (MSFC) to investigate ways of performing correlative space plasma research nationwide on a daily basis. As a first step, a user group was formed called the Data Systems Users Working Group (DSUWG) to provide the space science community interaction and direction in the project. After the first meeting of the DSUWG in September 1980, it was decided that the approach would be to design, build, and operate a spacecraft mission independent science network as a test case. In addition, the construction of the system would be designed to use existing data analysis computer systems at space physics institutions and to take full advantage of "off-the-shelf" software and hardware. The Space Physics Analysis Network (SPAN) first became operational in December 1981 with three major nodes: o University of Texas at Dallas o Utah State University o MSFC Since that time it has grown rapidly. Once operational, SPAN immediately started to facilitate space-data analysis by providing electronic mail, document browsing, access to distributed data bases, facilities for numeric and graphic data transfer, access to Class VI machines, and entry to gateways for other networks. The DSUWG continues to provide guidance for SPAN growth and seeks to identify, promote, and implement appropriate standards for the efficient management and exchange of data, related information, and graphics. All SPAN member organizations are expected to participate in the DSUWG. The basic composition of the DSUWG is a representative scientist and computer systems manager (who has the networking responsibility) at each of the member institutions. DSUWG meetings are held regularly at approximately nine month intervals. The DSUWG is structured along lines conducive to addressing major outstanding problems of scientific data exchange and correlation. There is a chairman for each subgroup to coordinate and focus the group's activities and a project scientist to oversee the implementation of the DSUWG recommendations and policies. The working group itself is divided into several subgroups which address issues of policy, networking and hardware, software and graphics standards, and data base standards. The DSUWG is a dynamic, evolving organization. We expect members to move in (or out) as appropriate to their active involvement in data related issues. We also realize that at present SPAN and the DSUWG are dealing with only a limited portion of the whole spectrum of problems facing the NASA research community. As present problems are solved, as the network evolves, and as new issues arise, we look to the DSUWG to reflect these changes in it's makeup, structure, and focus. The SPAN is currently managed by the National Space Science Data Center (NSSDC) located at Goddard Space Flight Center (GSFC). All SPAN physical circuits are funded by the Communication and Data Systems Division at NASA Headquarters. Personnel at the NSSDC facility, at the NASA SPAN centers, and the remote institutions work in unison to manage and maintain the network. Network Configuration and Evolution ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The initial topology for SPAN was a modified star where all communication with the remote institutions came to a major central switching or message routing node at MSFC. This topology served the network well until many new nodes were added and more scientists became accustomed to using the network. As data rate demands on the network increased, it was apparent that a new topology using lines with higher data rates was needed. Toward this end, a new communication architecture for SPAN was constructed and implemented. The current structure of SPAN in the United States is composed of an interconnected four-star, mesh topology. Each star has, as its nucleus, a SPAN routing center. The routing centers are located at GSFC, MSFC, Jet Propulsion Lab (JPL), and Johnson Space Center (JSC). The routing centers are linked together by a set of redundant 56 kbps backbone circuits. Tail circuits, at speeds of 9.6 kbps (minimum line speed), are connected to each routing center and and into the SPAN backbone. Most remote institutions have local area networks that allow a number of different machines to be connected to SPAN. Regardless of a machine's position in the network, all computers on SPAN are treated logically equal. The main goal of the new SPAN architecture is for a node that is located across the country through two routing centers to be as transparently accessible as a SPAN node sharing the same machine room with the originating system. This ease of use and network transparency is one of SPAN's greatest assets. The new configuration allows for rapid expansion of the network via the addition of new tail circuits, upgrade to existing tail circuits, and dynamic dialing of higher data-rate backbone circuits Implementation of this new configuration began in July 1986, and the new topology was completed in November 1986, although there are new circuits being added on a continuing basis. It is expected that a fifth routing center located at Ames Research Center. Nearly all of the machines on SPAN are linked together using the commercially available software package DECnet. DECnet allows suitably configured computers (IBM-PCs and mainframes, SUN/UNIX workstations, DEC/PROs, PDPs, VAXs, and DECSYSTEMs) to communicate across a variety of media (fiber optics, coax, leased telephone lines, etc.) utilizing a variety of low level protocols (DDCMP, Ethernet, X.25). There are also several institutions that are connected through Janus hosts which run more then one protocol. SPAN links computers together and touches several other networks in the United States, Europe, and Canada that are used for data analysis on NASA spaceflight missions and other NASA related projects. At this time, there are well over 1200+ computers that are accessible through SPAN. DECnet networks has been accomplished by the unprecedented, successful cooperation of the network management of the previously separate networks. For example, the International High Energy Physics Network (HEPNET), the Canadian Data Analysis Network (DAN) and the Texas University Network (TEXNET) now have nonconflicting network addresses. Every node on each of these networks is as accessible to SPAN users as any other SPAN node. The mutual cooperation of these WANs has given enhanced capabilities for all. There are several capabilities and features that SPAN is developing, making it unique within the NASA science community. The SPAN system provides remote users with access to science data bases and brings scientists throughout the country together in a common working environment. Unlike past NASA mission networks, where the remote sites have only remote terminals (supporting one person at the remote site at a time), SPAN supports many users simultaneously at each remote node through computer-to-remote computer communications software. Users at their institutions can participate in a number of network functions involving other remote computer facilities. Scientific papers, data and graphics files can easily be transferred between network nodes. This significantly reduces the time it takes to perform correlative work when authors are located across the country or ocean. As an introduction to SPAN's network wide capabilities. More advanced users are referred to the DEC DECnet User's Manual. SPAN will continue to be used as a test case between NASA science investigators with the intent of exploring and employing modern computer and communication technology as a tool for doing NASA science research. This can be accomplished because SPAN is not a project dependent system that requires a static hardware and software configuration for the duration of a mission. SPAN has provided a quick reaction capability for several NASA and ESA missions. Each of these missions needed to rapidly move near real-time ground and spacecraft observations to a variety of destinations for analysis and mission planning. Because of SPAN's great success, new NASA spaceflight missions are seriously looking into creating networks with similar capabilities that are internetworked with SPAN. Within the next few years, new developments in software and hardware will be implemented on SPAN that will continue to aid NASA science research. It is anticipated that SPAN will greatly improve its access to gateways into Europe and other locations throughout the world. As a natural evolution, SPAN will migrate toward the International Standards Organization's (ISO) Open Systems Interconnect (OSI) protocol as the software becomes available. It is expected that the ISO/OSI protocol will greatly enhance SPAN and increase the number of heterogeneous computer systems accessible. Security And Conduct On The Network ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Misconduct is defined as: 1. Any unauthorized access or use of computers on the network, 2. Attempts to defeat computer security systems (e.g. violating a captive account), 3. Repeated login failures to computers or privileged accounts to which the user is not authorized to use, 4. Massive file transfers from a given site without prior consent and coordination with the appropriate SPAN routing centers. The network is monitored very closely, and it is relatively simple to spot an attempted break-in and then track down the source. When a violation is found, the matter will be reported to the DSUWG steering committee and the SPAN line will be in immediate danger of being disconnected. If the situation cannot be resolved to the satisfaction of both the DSUWG steering committee and network management, the SPAN line to the offending site will be reviewed for the possibility of permanent disconnection. In short, NASA pays for the communications lines and will not tolerate misconduct on the network. SPAN Network Information Center (SPAN-NIC) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The SPAN-NIC is located at the National Space Science Data Center in Greenbelt, Maryland. The purpose of the SPAN-NIC is to provide general user services and technical support to SPAN users via telephone, electronic mail, and postal mail. As SPAN has grown exponentially over recent years, it was realized that a central organization had to be developed to provide users with technical assistance to better utilize the resources that the network provides. This is accomplished by maintaining and distributing relevant technical documents, providing user assistance on DECnet related questions, monitoring traffic on the network, and maintaining an online data base of SPAN node information. More specific information on becoming a SPAN site, beyond that provided in this document, can also be obtained through SPAN-NIC. The SPAN-NIC uses a VAX 8650 running VMS as its host computer. Users wishing to use the online information services can use the account with the username SPAN_NIC. Remote logins are capable via SET HOST from SPAN, TELENET from ARPANET and by other procedures detailed later. SPAN-NIC DECnet host address: NSSDCA or 6.133 SPAN-NIC ARPANET host address: NSSDC.ARPA or 128.183.10.4 SPAN-NIC GTE/TELENET DTE number: 311032107035 An alternative to remote login is to access online text files that are available. These text files reside in a directory that is pointed to by the logical name "SPAN_NIC:". Example commands for listing this directory follow: From SPAN: $ DIRECTORY NSSDCA::SPAN__NIC: From ARPA: FTP> ls SPAN__NIC: The available files and a synopsis of their contents can be found in the file "SPAN_NIC:SPAN_INDEX.TXT". Once a file is identified, it can be transferred to the remote host using the VMS COPY command, or the FTP GET command. It is important to note that this capability will be growing significantly not only to catch up to the current SPAN configuration but also keep current with its growth. DECnet Primer ~~~~~~~~~~~~~ The purpose of the SPAN is to support communications between users on network nodes. This includes data access and exchange, electronic mail communication, and sharing of resources among members of the space science community. Communication between nodes on the SPAN is accomplished by means of DECnet software. DECnet software creates and maintains logical links between network nodes with different or similar operating systems. The operating systems currently in use on SPAN are VAX/VMS, RSX, and IAS. DECnet provides network control, automatic routing of messages, and a user interface to the network. The DECnet user interface provides commonly needed functions for both terminal users and programs. The purpose of this section of the file is to provide a guide on the specific implementation of DECnet on SPAN and is not intended to supercede the extensive manuals on DECnet already produced by DEC. DECnet supports the following functions for network users: 1. TASK-TO-TASK COMMUNICATIONS: User tasks can exchange data over a network logical link. The communicating tasks can be on the same or different nodes. Task-to- task communication can be used to initiate and control tasks on remote nodes. 2. REMOTE FILE ACCESS: Users can access files on remote nodes at a terminal or within a program. At a terminal, users can transfer files between nodes, display files and directories from remote nodes, and submit files containing commands for execution at a remote node. Inside a program, users can read and write files residing at a remote node. 3. TERMINAL COMMUNICATIONS: RSX and IAS users can send messages to terminals on remote RSX or IAS nodes. This capability is available on VMS nodes by using the PHONE utility. 4. MAIL FACILITY: VMS users can send mail messages to accounts on remote VMS nodes. This capability is currently available for RSX and IAS nodes but is not supported by DEC. There are slight variations for RSX and IAS network mail compared to VMS mail. 5. REMOTE HOST: VMS, RSX, and IAS users can log-on to a remote host as if their terminals were local. Network Implementations For DECnet ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The SPAN includes implementations for RSX, IAS and VAX/VMS operating systems. DECnet software exists at all the SPAN nodes and it allows for the communication of data and messages between any of the nodes. Each of the network nodes has a version of DECnet that is compatible with the operating system of that node. These versions of DECnet have been presently developed to different extents causing some nodes to have more or less capabilities than other nodes. The version or "phase" of the DECnet, as it is called, indicates the capability of of that node to perform certain levels of communication. Since RSX and IAS implementations are almost identical, they are described together. Users need not have any special privileges (VAX/VMS users will need the NETMBX privilege on their account) to run network tasks or create programs which access the network. However users must supply valid access control information to be able to use resources. The term "access control" refers to the user name and password of an account (local or on a remote node). Online system documentation is a particularly important and valuable component of DEC systems. At the present, SPAN is comprised almost completely of DEC systems. An extensive set of system help files and libraries exists on all the SPAN DEC nodes. The HELP command invokes the HELP Utility to display information about a particular topic. The HELP utility retrieves help available in the system help files or in any help library that you specify. You can also specify a set of default help libraries for HELP to search in addition to these libraries. Format: HELP [keyword [...]] On many systems, new users can display a tutorial explanation of HELP by typing TUTORIAL in response to the "HELP Subtopic?" prompt and pressing the RETURN key. Utilities for DECnet-VAX ~~~~~~~~~~~~~~~~~~~~~~~~ VAX terminal users have several utility programs for network communications available from the VMS operating system. Documentation for most of these utilities can be found in the Utility Reference Manual of the VAX/VMS manual set, and each utility has extensive online help available. The following descriptions offer a brief introduction to these utilities: MAIL: The VAX/VMS mail utility allows you to send a message to any account or to a series of accounts on the network. To send a message, you must know the account name of the person you wish to contact and his node name or node number. (This will be covered more extensively later in this file). FINGER: The DECUS VAX/VMS Finger utility has been installed on a number of SPAN VAX/VMS systems. Finger allows a user to see who is doing what, both on his machine and on other machines on the network that support Finger. Finger also allows a user to find information about the location and accounts used by other users, both locally and on the network. The following is an example session using the FINGER utility. $ FINGER NSSDCA VAX 8600, VMS V4.3. Sunday, 28-Sep-1986 19:55,4 Users,0 Batch. Up since Sunday, 28-Sep-1986 14:28 Process Personal name Program Login Idle Location HILLS H.Kent Hills Tm 19:02 NSSDC.DECnet _RTA4: Dr. Ken Klenk Tm 17:55 NSSDC.DECnet _NVA1: Michael L. Gough Mail 15:13 SPAN Man Joe Hacker Finger 17:33 bldg26/111 $ FINGER SWAFFORD@NSSDCA [NSSDCA.DECnet] NSSDCA VAX/VMS, Sunday, 28-Sep-1986 19:55 Process Personal name Program Login Idle Location SPAN Man Finger 17:33 Logged in since: Sunday, 28-Sep-1986 17:33 Mail: (no new mail) Plan: Joe Hacker, SPAN Hackers Guild Telephone: (800)555-6000 If your VAX supports VMS Finger, further information can be found by typing HELP FINGER. If your system does not currently have the FINGER utility, a copy of it is available in the form of a BACKUP save set in the file: NSSDCA::SPAN_NIC:FINGER.BCK PHONE: The VAX/VMS PHONE utility allows you to have an interactive conversation with any current user on the network. This utility can only be used on video terminals which support direct cursor positioning. The local system manager should know if your terminal can support this utility. To initiate a phone call, enter the DCL command PHONE. This should clear the screen and set up the phone screen format. The following commands can be executed: DIAL nodename::username Places a call to another user. You must wait for a response from that user to continue. DIAL is the default command if just nodename::username is entered. ANSWER Answers the phone when you receive a call. HANGUP Ends the conversation (you could also enter a CTRL/Z). REJECT Rejects the phone call that has been received. DIR nodename:: Displays a list of all current users on the specified node. This command is extremely useful to list current users on other nodes of the network. FACSIMILE filename Will send the specified file to your listener as part of your conversation. To execute any of these commands during a conversation, the switch hook character must be entered first. By default, that character is the percent key. REMOTE FILE ACCESS: DCL commands that access files will act transparently over the network. For example, to copy a file from a remote node: $copy From: node"username password"::disk:[directory]file.lis To: newfile.lis This will copy "file.lis" in "directory" on "node" to the account the command was issued in and name it "newfile.lis". The access information (user name and password of the remote account) is enclosed in quotes. Note that you can also copy that same file to any other node and account you desire. For another example, to obtain a directory listing from a remote node, use the following command: $dir node::[directory] (if on the default disk) Utilities for DECnet-11M/DECnet-IAS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ There are certain DECnet functions that can only be done on nodes that have the same type of operating systems, such as the MPB, TRW, SPRL, LASR, and UTD nodes all with an RSX-11M operating system. The capabilities offered to the RSX DECnet user can be broken down into two major categories: those functions for terminal users and those functions for FORTRAN programmers. DECnet-11M terminal users have several utility programs available to them which allows logging onto other machines in the network, file transfers, message communication, and network status information. REMOTE-LOGON: The REMOTE-LOGON procedure allows a user at a node to log-on to another node in the network. This capability is also called virtual terminal. The "SET /HOST=nodename" command allows the user to log-on to adjacent nodes in the network from a DECnet-11M node. This command is initiated by simply typing "SET /HOST=nodename". The "SET HOST" command on the SPAN-VAX also allows you to log-on to adjacent nodes. NETWORK FILE TRANSFER: NFT is the Network File Transfer program and is part of the DECnet software. It is invoked by typing NFT to file = from file or by typing NFT to file = from file. Embedded in the file names must be the node name, access information, and directory if it is different than the default conventions. Also note that file names can only be 9 (nine) characters long on RSX systems. Therefore, VAX/VMS files with more than 9 characters will not copy with default-file naming. In such a case you must explicitly name the file being copied to an RSX system. The following structure for the file names must be used when talking to the SPAN nodes with NFT. NODE/username/password::Dev:[dir.sub-dir]file.type The following NFT switches are very useful: /LI Directory listing switch. /AP Appends/adds files to end of existing file. /DE Deletes one or more files. /EX Executes command file stored on remote/local node. /SB Submits command file for execution (remote/local). /SP Spools files to the line printer (works only with "like" nodes). A particular use for NFT is for the display of graphics files on the network. It is important to note, however, that some device-dependent graphics files are not all displayable, such as those generated by IGL software. The graphic files generated by graphic packages that are displayable when residing at other nodes may be displayed by using the following input: NFT> TI:=SPAN/NET/NET::[NETNET.RIMS]D1364.COL Graphics files generated by IGL can be displayed by running either REPLAY or NETREP programs (see the net-library documentation). TERMINAL COMMUNICATIONS: TLK is the Terminal Communications Utility which allows users to exchange messages through their terminals. TLK somewhat resembles the RSX broadcast command but with more capabilities. TLK currently works only between RSX-11 nodes and within a RSX-11 node. There are two basic modes of operation for TLK: The single message mode and the dialogue mode. The single message mode conveys short messages to any terminal in the same node or remote node. The syntax for this operation is: >TLK TARGETNODE::TTn:--Message-- To initiate the the dialogue mode type: >TLK TARGETNODE::TTn When you receive the TLK> prompt, you can enter a new message line. Graphics Display Utilities ~~~~~~~~~~~~~~~~~~~~~~~~~~ One of the main objectives of the SPAN system project is to accommodate coordinated data analysis without leaving one's institution. Therefore, there is a strong need to develop the ability to have graphic images of data from any node to be displayed by any other node. The current inability to display data on an arbitrary graphics device at any node has been quickly recognized. As general network utilities are developed to support the display of device dependent and independent graphic images, the handbook SPAN Graphics Display Utilities Handbook will serve to document their use and limitations. The graphics handbook is a practical guide to those common network facilities which will be used to support network correlative studies from the one-to-one to the workshop levels. For each graphics software utility the handbook contains information necessary to obtain, use, and implement the utility. Network Control Program ~~~~~~~~~~~~~~~~~~~~~~~ NCP is the Network Control Program and is designed primarily to help the network manager. However, there are some NCP commands which are useful for the general user. With these commands, the user can quickly determine node names and whether nodes are reachable or not. Help can be obtained by entering NCP>HELP and continuing from there. For a complete listing of all the NCP commands that are available to nonpriviledged users, refer to the NCP Utility manual on VAXs, and the NCP appendix of the DECnet-11M manual for PDPs. The following two commands are probably the most beneficial to users: $ RUN SYS$SYSTEM:NCP !on VAXs -or- > RUN $NCP !on PDPs NCP> SHOW KNOWN NODES !show a list of all nodes ! defined in the volatile data base NCP> SHOW ACTIVE NODES !show a list of only currently reachable Please note that the second command cannot be used on "end nodes", that is, nodes that do not perform at least DECnet Level I routing. In addition, only nodes in the user's area will be displayed on either Level I or Level II routers. In the case of end nodes, users should find out the name of the nearest Level I or II routing node and issue the following command: NCP> TELL GEORGE SHOW ACTIVE NODES Mail ~~~~ As briefly discussed earlier all SPAN DEC nodes have a network mail utility. Before sending a mail message, the node name and user name must be known. To send a message to the project manager, you would enter the following commands: $ MAIL MAIL> SEND To: NSSDCA::THOMAS Subj: MAIL UTILITY TEST Enter your message below. Press ctrl/z when complete ctrl/c to quit: VALERIE, OUR NETWORK CONNECTION IS NOW AVAILABLE AT ALL TIMES. WE ARE LOOKING FORWARD TO WORKING FULL TIME ON SPAN. THANKS FOR ALL YOUR HELP. FRED MAIL>EXIT In order to send mail to more than one user, list the desired network users on the same line as the TO: command, separating each with a comma. Another way to accomplish this is to use a file of names. For example, in the file SEPAC.DIS, all SEPAC investigators on SPAN are listed: SSL::ROBERTS SSL::REASONER SSL::CHAPPELL SWRI::JIM TRW::TAYLOR STAR::WILLIAMSON The network mail utility will send duplicate messages to all those named in the above file by putting the file name on the TO: command line (TO: @SEPAC). A second option for the SEND command is to include a file name that contains the text to be sent. You will still be prompted for the To: and Subject: information. The following statements give a brief description of other functions of the MAIL utility: READ n Will list, on the terminal, the mail message corresponding to number n. If n is not entered, new mail messages will be listed. EXTRACT Saves a copy of the current message to a designated file. FORWARD Sends a copy of the current message to other users. REPLY Allows you to send a message to the sender of the current message. DIR Lists all messages in the current folder that you have selected. The sequence numbers can then be used with the READ command. DEL Delete the message just read. The message is actually moved to the WASTEBASKET folder until you exit the utility, when it is actually deleted. Therefore, you can retrieve a message that you have "deleted", up until you enter "exit" or ^Z to the MAIL> prompt. HELP Always useful if you're lost. Remote Node Information Files ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ All nodes on the SPAN are required to maintain two node specific information files in their DECnet default directories. The first file is a network user list file that contains specific information on each network user who has an account on the machine. At a minimum, the user list file should contain the name of the user, his electronic mail address, his account/project identifier, and his default directory. All of this information is easily obtained on VAX/VMS systems from the SYS$SYSTEM:SYSUAF.DAT file. (Note that the SYSUAF.DAT file is (and should be) only readable by the system manager.) The file is called USERLIST.LIS and resides in the node's DECnet default directory. A command procedure for creating this file is available in NSSDCA::SPAN_NIC:USERLIST.COM. This procedure should be executed from the SYSTEM account on the remote node for which it is to be compiled. Following is an example of displaying the USERLIST.LIS file on NSSDCA from a VAX/VMS system. $ TYPE NSSDCA::USERLIST Userlist file created at : 28-SEP-1986 22:06:01.71 Owner Mail Address Project Default Directory ---------------- ----------------- --------- ----------------- ROBERT HOLZER NSSDCA::HOLZER CD8UCLGU CDAW_C8USER:[HOLZER] RICHARD HOROWITZ NSSDCA::HOROWITZ ACQ633GU ACQ_USER:[HOROWITZ] CHERYL HUANG NSSDCA::HUANG CD8IOWGU CDAW_C8USER:[HUANG] DOMINIK P. IASCO NSSDCA::IASCONE PCDCDWPG CDAW_DEV:[IASCONE] ISADARE BRADSKY NSSDCA::IZZY DVDSARPG DAVID_DEV:[IZZY] WENDELL JOHNSON NSSDCA::JOHNSON DCSSARPG CODD_DEV:[JOHNSON] DAVID JOSLIN NSSDCA::JOSLIN SYSNYMOP OPERS_OPER:[JOSLIN] JENNIFER HYESONG NSSDCA::JPARK CAS130GU CAS_USER:[JPARK] HSIAOFANG HU NSSDCA::JUDY DVDSARPG DAVID_DEV:[JUDY] YOUNG-WOON KANG NSSDCA::KANG ADCSARGU ADC_USER:[KANG] SUSAN E. KAYSER NSSDCA::KAYSER ACQSARGU ACQ_USER:[KAYSER] DR. JOSEPH KING NSSDCA::KING ADM633MG ADM_USER:[KING] BERNDT KLECKER NSSDCA::KLECKER CD8MAXGU CDAW_C8USER:[KLECKER] KENNETH KLENK NSSDCA::KLENK PCDSARPG ADM_USER:[KLENK] Much like the user list, a node information listing is available for all nodes in their DECnet default account. This file is named NODEINFO.LIS. The following example is for the SSL node and should be taken as a template for the generic NODEINFO.LIS file that should be on each node in SPAN. $ TYPE SSL::NODEINFO Telenet Access To SPAN ~~~~~~~~~~~~~~~~~~~~~~ As SPAN grows, the number of users wishing to make use of its capabilities increases dramatically. Now it is possible for any user with a terminal and a 0.3 or 1.2 kbps modem to access SPAN from anywhere in the U.S. simply by making a local telephone call. There exists an interconnection between SPAN and the NASA Packet Switched Service (NPSS). The NPSS in turn has a gateway to the public GTE Telenet network which provides the local call access facilities. The user dials into one of Telenet's local access facilities and dials the NASA DAF (Data Access Facility) security computer. The user is then able to access SPAN transparently through the NSSDC or SSL machines. To find the phone number of a PAD local to the area you are calling from, you can call the Telenet customer service office, toll free, at 1-800-TELENET. They will be able to provide you with the number of the nearest Telenet PAD. The following outlines the steps that one must go through to gain access to SPAN through Telenet. 1. First dial into the local Telenet PAD. 2. When the PAD answers, hit carriage return several times until the '@' prompt appears. @ 3. Next enter the host identification address of the NASA DAF (security computer). This identification was not yet available at publication time, but will be made available to all users requesting this type of access. @ID ;32100104/NASA 4. You will then be prompted for a password (which will be made available with the identification above). PASSWORD = 021075 (Note: Tthe password will not be echoed) 5. Then type . You will be connected to the NASA DAF computer. The DAF will tell you which facility and port you succeeded in reaching, along with a "ready" and then an asterisk prompt: NASA PACKET NETWORK - PSCN TROUBLE 205/544(FTS 824)-1771 PAD 311032115056 *1 ready * All entries to the DAF must be in capital letters, and the USERID and PASSWORD will undoubtedly be echoed on the screen. *LOGON ENTER USERID> LPORTER ENTER PASSWORD> XXXXXXX ENTER SERVICE> SPANSSL NETWORK CONNECTION IN PROGRESS connected Alternatively, you may enter NSSDC for the "Service>" request. 6. You should now get the VMS "Username" prompt: Username: SPAN 7. You will then be prompted for the name of the SPAN host destination. For instance, if you are a Pilot Land Data System user on the NSSDC VAX 11/780, you would enter NSSDC and hit the carriage return in response to the prompt for host name. SPAN host name? NSSDC 8. Finally, continue with normal logon procedure for the destination host. The SPAN X.25 gateways have also been used extensively for internetwork communications to developing networks in Europe and Canada. The traffic from the United States to Europe was so extensive that a dedicated link between the GSFC and ESOC routing centers. This link became operational in January 1987. Configuration Of SPAN/TELENET Gateway ---------- | dial-up| | user | ---------- | ------------------------- | TELENET | ------------------------- | gateway ------------------------- | NPSS | ------------------------- | | ----------- ----------- | SSL | | NSSDC | | VAX 780 | | VAX 8650| ----------- ----------- | | ------------------------- | SPAN | ------------------------- | | | | ------ ------ ------ ------ |SPAN| |SPAN| |SPAN| |SPAN| |node| |node| |node| |node| ------ ------ ------ ------ SPAN/ARPANET/BITNET/Public Packet Mail Gateways ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ SPAN supports several gateways both to and from several major networks. The following gives the current syntax for forming an address to another user on another network. There are several similar gateways at other SPAN nodes that are not included in this list. Stanford is used here only as a typical example. If it is necessary for you to use the Stanford mail gateway on an occasional basis, you should obtain permission from the system manager on the STAR node (or any other non-NASA gateway node). Currently, there is no restriction on the NSSDCA gateway usage. SPAN-to-ARPANET: NSSDC Gateway . . To: NSSDCA::ARPA%"arpauser@arpahost" JPL Gateway . . . To: JPLLSI::"arpauser@arpahost" Stanford Gateway. To: STAR::"arpauser@arpahost" ARPANET-to-SPAN: NSSDC Gateway . . To: spanuser%spanhost.SPAN@128.183.10.4 JPL Gateway . . . To: spanuser%spanhost.SPAN@JPL-VLSI.ARPA Stanford Gateway. To: spanuser%spanhost.SPAN@STAR.STANFORD.EDU [Note: 128.183.10.4 is MILNET/ARPANET address for the NSSDC] SPAN-to-BITNET: NSSDC Gateway. . .To: NSSDCA::ARPA%"bituser%bithost.BITNET@CUNY.CUNYVM.EDU" JPL Gateway. . . .To: JPLLSI::"bituser%bithost.BITNET@CUNY.CUNYVM.EDU" Stanford Gateway .To: STAR::"bituser%bithost.BITNET@CUNY.CUNYVM.EDU" BITNET-to-SPAN: Stanford Gateway. . . . To: spanuser%spanhost.SPAN@SU-STAR.ARPA The following gateways allow users on a VAX that supports a connection to a public packet switch system (virtually anywhere in the world) to reach SPAN nodes and vice-versa. Note that this will transmit mail only to and from VAXs that support DEC PSI and PSI incoming and outgoing mail. SPAN-to-Public Packet VAX NSSDC Gateway. To: NSSDCA::PSI%dte_number::username SSL Gateway. . To: SSL::PSI%dte_number::username Public Packet VAX-to-SPAN node NSSDC Gateway. To: PSI%311032107035::span_node_name::username SSL Gateway. . To: PSI%311032100160::span_node_name::username It is possible for remote terminal access and mail between users on England's Joint Academic Network (JANET) and SPAN. JANET is a private X.25 network used by the UK academic community and is accessible through the two SPAN public packet switched gateways at MSFC and at the NSSDC. List Of Acronyms ~~~~~~~~~~~~~~~~ ARC - Ames Research Center ARPANET - Advanced Research Projects Agency network BITNET - Because It's Time Network CDAW - Coordinated Data Analysis Workshop CSNET - Computer Science Network DDCMP - DEC "level II" network protocol DEC - Digital Equipment Corporation DECnet - DEC networking products generic family name DSUWG - Data System Users Working Group ESOC - European Space Operations Center ESTEC - European Space Research and Technology Center GSFC - Goddard Space Flight Center GTE - General Telephone and Electic HEPNET - High Energy Physics Network INFNET - Instituto Nazional Fisica Nucleare Network ISAS - Institute of Space and Astronautical Science ISO/OSI - International Standards Organization/Open Systems Interconnection (network protocol) ISTP - International Solar Terrestrial Physics JANET - Joint Academic Network (in United Kingdom) JPL - Jet Propulsion Laboratory JSC - Johnson Space Center kbps - Kilobit per second LAN - Local area network LANL - Los Alamos National Laboratory MFENET - Magnetic Fussion Energy Network MILNET - Defence data network (originally part of ARPANET) MSFC - Marshall Space Flight Center NCAR - National Center for Atmospheric Research NFT - Network File Transfer (program on RSX/IAS systems) NIC - Network Information Center NPSS - NASA Packet Switched System (using X.25 protocol) NSSDC - National Space Science Data Center (at GSFC) PDS - Planetary Data System PSCN - Program Support Communications Network SESNET - Space and Earth Science Network (at GSFC) SPAN - Space Physics Analysis Network SSL - Space Science Laboratory (at MSFC) RVT - Remote virtual terminal program for RSX or IAS systems TCP/IP - Transmission Control Protocol/Internet Protocol Telenet - A public packed switched network owned by GTE TEXNET - Texas Network (Academic network) WAN - Wide area network X.25 - A "level II" communication protocol for packet switched networks _______________________________________________________________________________