You can configure Telix to set up your computer as a remote host, so that others may call your system and perform operations like transferring files and chatting. It is like having a small BBS on your system. However, if your security needs are complicated you should consider using a real BBS program. There are a few requirements to running Host Mode. Your modem must be able to pick up the phone when it rings. The CD (Carrier Detect) Mask must be properly defined in the Configuration Menu, so that Telix can tell when it is connected to a caller. Telix must also be able to hang up the modem by dropping (turning off) the DTR line on the RS-232 port. If one of these requirements is not met you probably can not run Telix Host Mode on your system. The Telix Host Mode is set in motion as a script in Telix's powerful SALT script language. To run the Host Mode script, press Alt-G while in Terminal mode, and then enter 'HOST' as the script file name. The script 'HOST' will then be run. Several Host Mode configuration settings are kept in a file called 'HOST.CNF'. The first time you run the Host Mode script, it will not find this file, and automatically run the host Mode configuration script 'HCONFIG', which will create the file and allow you to change default values. You should run HCONFIG when you need to configure the Host Mode. HCONFIG will present you with the following parameters: A: Level One password. This is the password that callers must successfully enter to be admitted to the Host Mode and have Level One access. B: Level two password. This is the password that callers must successfully enter to be admitted to the Host Mode and have Level Two (Sysop) access. C: DOS shell password. This is the password that users of the Host Mode have to enter to use the Remote DOS Shell option. D: Shut down Host Mode password. This is the password that callers must enter to shut down the Host Mode, when they press Ctrl-Z. E: Host Download Directory. Level 1 access callers will only be able to download (have Telix send them) files that are in this directory. As well, the 'F'iles command will show them only the contents of this directory. !! CAUTION !! DO NOT, UNDER ANY CIRCUMSTANCES, define this directory to the same name as the directory you run Telix in. If you did that, callers could download the Host Mode configura- tion file, which is stored there, and see your passwords. Level 2 access callers may specify any download path, but this is the default. F: Host Upload Directory. Level 1 access callers will only be able to upload (send to Telix) files into this directory. Level 2 access callers can specify any path, but files will go here by default. G: Connection type. This can be either 'Modem' or 'Direct'. Use 'Modem' if your host system is being accessed through a modem, or 'Direct' if two computers are hard-wired. This stops Telix from trying to initialize a non-existent modem. or trying to determine the caller's baud. There is one other important parameter which must be properly set for Host Mode operation. This is the Auto Answer string, which is defined in the 'Modem and dialing' page of the Configuration Menu. This string is sent to the modem when Telix enters Host Mode, and should make the modem pick up the phone when it rings. The default string is set up for Hayes compatible modems. It is: 'AT X1 S0=1|^M' where AT The modem attention code. X1 Tells the modem to reply with extended result codes. This means the modem indicates the caller's baud rate. S0=1 Tells the modem to answer after one ring. ^M Sends the terminating Carriage Return character. There are two optional text files which are displayed to callers if they exist, called LOGO.MSG, and WELCOME.MSG. The Host Mode can actually be run once it's configured. Telix will make a note in the Host Mode audit file HOST.LOG and then will immediately send the Host Mode init string to the modem. Telix then waits for a caller. While in Host Mode, on the local side, the user can always press Esc to exit Host Mode, or End to terminate the current caller. He can also enter commands for the remote caller, so that a novice caller can be helped along by the host operator. Also the current caller will be automatically terminated if there is inactivity for five minutes, or the connection is lost. This is all noted in the host audit file. If the caller has only access Level One, references to other disk directories than the ones defined in HCONFIG are ignored. All operations take place in the defined directories. Telix protects your files from being accidentally overwritten by the caller as well. Telix knows a caller is online when the Carrier Detect signal turns on. At this point, Telix will try to determine the caller's baud rate. Most Hayes compatible modems can be initialized to send the string 'CONNECT baud' where baud is the baud rate of the caller, when they sense a connection. If Telix sees this string it will switch to the appropriate baud. If this string is not received within a few seconds of the connection, Telix will leave the baud rate at whatever it was. Also, it should be mentioned that Telix can not determine the caller's other settings like parity, data bits, and stop bits. These must already match Telix's settings. If the file LOGO.MSG exists in the Telix directory it is displayed to the caller. Basically, it should identify the system. Then Telix will ask the caller for his/her name. The name must be at least five letters long and is only used when indicating the caller in the Host Mode audit file. If a password has been defined Telix will ask the caller for it. The caller has three tries to complete the password. All password attempts, successful or failed, are written to the Host audit file. If the caller enters the Level One access password, he may manipulate only the disk directories defined in HCONFIG. Any other directories can not be accessed. If he enters the Level Two access password, the caller may use full pathnames in all file specifications. The level 2 password should only be kept for yourself or those you completely trust, as a Level 2 caller can access any files on your system. If there is a file called WELCOME.MSG in the Telix directory, it is shown to the caller. This file can contain further identification or news that you only want valid callers to see. After each 23 lines the caller is prompted to press any key to continue. The caller may press Ctrl-S to pause at any time, and Ctrl-C or Ctrl-K to abort the listing. After the TELIX.MSG file is displayed the caller is presented with a menu of options: 旼컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� � �Files Type Upload Download Shell Chat Goodbye ? � 읕컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� The action to be taken is selected by entering its first letter. Case does not matter. The host operator is free to enter any keystrokes for the caller. The 'Files' option allows the caller to list the files in the current disk directory. The caller must press a key after each screen. The output is not echoed on the local screen. If the caller has access level two they are prompted for a filespec, which may include the * and ? wildcard characters so that the contents of other directories than the 'Host download dir' may be listed. The 'Type' option allows the caller to view any ASCII file in the Host Download Directory, or in any directory for access Level 2 callers. The same format and commands are available during this command as for the displaying of the optional message file TELIX.MSG. The 'Upload' option allows the caller to send a file to the host. The caller is shown the following menu: 旼컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� � Modem7 SEAlink Xmodem 1k-Xmodem G-1k-Xmodem Ymodem Ymodem-g � � Which protocol? � 읕컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴� The caller should select the appropriate protocol by its first letter (or 'E' for Ymodem-g). The caller is also asked for the filename. The transfer is then initiated. Level 1 callers may only upload files into the 'Host Upload Directory' defined with HCONFIG. The 'Download' command allows a caller to receive a file from the host. The caller must select the protocol as described above, and then must tell Telix the file(s) to send. The transfer is then initiated. Level 1 access callers may only download files from the 'Host Download Directory' defined with HCONFIG. The 'Shell' command is very powerful. It is also very dangerous command. It allows the caller to run a DOS shell on your system, except that the caller receives the output, and the caller enters the keystrokes. This command is basically similar to entering 'CTTY COMx' at the DOS prompt. The remote side has complete control of your system. !! This is obviously very dangerous !! The caller can format disks, delete files, or perform any other operation. A password must be entered to use the remote DOS shell to provide security. !! BE VERY CAREFUL WHOM YOU GIVE THIS PASSWORD TO !! They can do anything they want with your system. As well, don't leave it at the default that Telix comes with. There are a few limitations in the remote DOS shell. The caller will see program output only if the programs use standard DOS output. Programs that write directly to the video screen will work, but will not be seen by the remote caller. As well, programs that use non-DOS methods of getting keystrokes will not receive the callers keystrokes. Finally, under some systems, if the caller presses Backspace at the DOS prompt when the current line is empty, DOS will hang on the Host machine. As these are functions of DOS, there is nothing that can be done about these limita- tions. The 'Chat' command allows the caller to chat with the host operator. When the caller presses 'C' the host operator is paged for 20 seconds. Press the Space bar to chat with the caller, or any other key not to. Accepting the chat will place you in Chat Mode, exactly as if you had used the Alt-Y command. The caller's keystrokes are echoed back to him/her however, so that he/she can see them. Finally, the 'Goodbye' command allows the caller to log off the host. An entry noting the time and date is made in the host audit file, and Telix then waits for a new caller. The caller may also use one other command that is not displayed in the menu. This is to shut down the Host Mode. If the caller presses Ctrl-Z and success- fully enters the shut down Host password defined in the Configuration Menu, the Telix Host Mode is shut down and Telix returns to whatever it was doing before Host Mode was initiated.