Tcp/Ip Index
Topics for Tcp/Ip

Settings

Telnet Block Size/Block Delay

Telnet Receive Data Mask

Telnet Null after CR

Admittance Processing

Tcp/Ip Configuration Admittance Data

Tcp/Ip Runtime Admittance Data

Connection Establishment

Tcp/Ip Connect

Topics for SLIP

Settings

SLIP Communications Parameters

SLIP Dial Paraeters

Telnet Block Size / Block Delay

Telnet Receive Data Mask

Telnet NULL after CR

   Admittance Processing

SLIP Configuration Admittance Data

SLIP Runtime Admittance Data

Connection Establishment

   SLIP Connect

SLIP Connection Parameters

General Introduction to using SLIP with SOFTERM

SLIP refers to the capability of providing Tcp/Ip networking over an asynchronous communications link.  This mechanism allows access to a Tcp/Ip capable system or a Tcp/Ip network.  The INTERNET is one such example of a Tcp/Ip network that could be connnected to via SLIP.

Typically, it is necessary to connect to the Tcp/Ip network via a modem and then negotiate a series of questions and answers in standard asynchronous mode before entering into Tcp/Ip SLIP mode.

The SOFTERM family of products provide a seamless integration of these two requirements though the SOFTERM SLIP connection path and the SOFTERM Tcp/Ip SLIP kernel.  Once a session has been built containing a SOFTERM SLIP connection path object and that session is started, SOFTERM will initialize the modem, dial the target system and allow the user to interact with the target system in order to perform some or all of the following tasks:

•	login

•	obtain a temporary IP address

•	enter SLIP mode

At this point, both Tcp/Ip and the SOFTERM session are ready to establish a Telnet session to the destination address specifed in the session object.

It is possible to further automate this connection process by adding an entry to the PHONES database file that defines the phone number and associates a series of batch commands with that number that are to be automatically executed when the session is started.

Batch Commands

Batch commands are defined with their associated PHONES database file entry.  They are used to perform automatic logons to remote systems, to decode ip addresses in the receive data stream that are to be used by the local PC and to enter SLIP mode.

Supported commands are:

SEND string[CR]

WAITFOR string SEND reply[CR]

WAITFOR_IP string

WAITFOR_NETMASK string

WAITFOR_GATEWAY string

SLIPMODE

where:

[CR] is a convenient method for representing the carriage return character when it is required in a string. [LF] may also be used to represent a line feed character.

Each string argument can be either a sequence of words enclosed in single(') or double(") quotes or can be a single word.

The SEND keyword defines a string that is to be transmitted immediately when a connection is established between the local PC and the Tcp/Ip system or network.

The WAITFOR keyword defines a string that when detected by the local PC in the receive data stream causes the associated SEND string to be transmitted to the Tcp/Ip system or network.

The WAITFOR_IP, WAITFOR_NETMASK and WAITFOR_GATEWAY keywords define lead-in strings for the local ip address, local ip address mask and gateway ip address respectively.  When one of these lead-in strings has been detected by the local PC in the receive data stream, the receive data stream is further monitored for the first valid ip address in dotted notation.  When a valid ip address has been assembled, that address is subsequently used by the Tcp/Ip kernel during Tcp/Ip operations.  These lead-in strings need only define a unique string that precedes an ip address somewhere in the receive data stream, they do not have to define the string immediately preceding the ip address.  When remote Tcp/Ip systems or networks provide these common capabilities, it avoids having to continually reconfigure and reinstall the Tcp/Ip kernel.

The SLIPMODE keyword causes the Tcp/Ip kernel to be readied for Tcp/Ip operations and placed into SLIP mode and causes the execution of batch commands to be terminated.  When specified, SLIP mode is initiated when the command immediately preceding the SLIPMODE command has been executed.


Tcp/Ip Configuration Admittance Data

This dialog allows you to specify the connection parameters for the Tcp/Ip connection.  The IP address, telnet port number, and initial handshake transmission may be specified.

Normally, the only field which requires input is the IP address field.  The telnet port number should be left with the "Use Default" checkbox checked unless you know that an alternate number should be used; this will cause the connection to be initiated on the default port number of 23.  The "Handshake Transmission" is normally left blank,  as most Tcp/Ip hosts respond once the connection is established.

If you wish to modify any of the parameters at the time the connection is initiated, use the checkbox "Display this dialog box at connect time".  Checking the field will cause this dialog to be presented when the runtime session is started so that the connection parameters may be changed before the connection is initiated.

To save the connection information under the current name, use the "Save" pushbutton.  To specify a new name, use the "Save as" pushbutton.


Tcp/Ip Runtime Admittance Data

This dialog allows you to modify the preset connection parameters for the Tcp/Ip connection.  The IP address, telnet port number, and initial handshake transmission may be modified.

Normally, the only field which requires change is the IP address field.  The telnet port number should be left with the "Use Default" checkbox checked unless you know that an alternate number should be used; this will cause the connection to be initiated on the default port number of 23.  The "Handshake Transmission" is normally left blank,  as most Tcp/Ip hosts respond once the connection is established.

This dialog is presented because the checkbox "Display this dialog box at connect time" was checked in the admittance data for this session.  You may change the setting at this time if you wish, and after pressing "Save" or "Save as", the dialog will not be presented on subsequent executions of this session profile.

To initiate the connection without updating the saved profile information, press "OK".  To save the connection information under the current name, use the "Save" pushbutton.  To specify a new name, use the "Save as" pushbutton.  To cancel this session, use "Cancel".


Tcp/Ip Dial
SLIP / Tcp/Ip Connect

This dialog monitors the progress of the connection.

In the case of a SLIP connection, this dialog initially monitors the progress of initializing the modem, dialing the remote system, and executing any batch commands associated with the phone number in the PHONES file.  If the phone number does not have an entry in the PHONES database file or the entry does not contain any associated batch commands, this dialog will be dismissed once the modem connection is complete.  The terminal emulation of the currrent session will be available for interactive use with the system connected to in order to allow login/password processing to be performed.  At the same time that this dialog is dismissed, another modeless dialog will be displayed that contains additional Tcp/Ip parameters.  When the interactive mode is complete, Telnet session establishment will be initiated when this modeless dialog is dismissed by pressing the "OK" pushbutton.

No preset time limit is applied and an attempt to establish the Telnet session is continued until the Tcp/Ip transport layer signals that the connection attempt has failed, or you press the "Cancel" pushbutton.


SLIP Communications Parameters

This dialog allows a modem and associated communications parameters to be specified for an asynchronous communications connection to a SLIP capable system or to a SLIP router.

Modem

Baud Rate

Data Bits, Stop Bits, Parity


SLIP Dial Parameters

This dialog allows a phone number to be specified that will be used to establish an asynchronous communications connection to a SLIP capable system or to a SLIP router.

Number to Dial

Phone Numbers

Wait For Carrier Timeout

Execute Batch Commands Timeout


Telnet Block Size/Block Delay

This dialog allows the selection of the maximum amount of telnet data which is to be transmitted in a single block and the minimum amount of time between successive transmitted blocks.  These items should be left at their default values unless you have a specific problem which modification of these parameters may solve.

Block Size

Inter-Block Delay


Telnet Receive Data Mask

This dialog allows selection of 7 or 8 data bits per data character.

Mask Receive Data to 7bits


Telnet Null after CR

This dialog allows control over the insertion and deletion of null characters which follow carriage returns in the Telnet data stream.

Strip null following received carriage return

Do not add null after transmitted carriage return


IP address / host name

This field is used to specify the target host with which to establish the Tcp/Ip connection.  Either an IP address in dotted decimal notation or an alphanumeric host name may be used.


Telnet port - Use default

This checkbox allows you to select the default port number on which to establish the Tcp/Ip Telnet connection.  The default port number is 23, and is used for almost all terminal telnet connections.

If this field is checked, input to the "Specific port #" field is disabled.  If this field is not checked, the desired port number may be entered.


Telnet port - Specific port #

This field is used to specify a port number other than the Tcp/Ip Telnet default of 23.  If the "Use default" checkbox is checked, entry into this field is disabled.  Otherwise, you may enter the desired Tcp/Ip port for this telnet connection.


Handshake Transmission

This field is optional.

Enter a string to be transmitted to the host as soon as a valid connection is made.  This could be as simple as a carriage return, [CR], to "wake up" the remote system.

This field is normally left blank, as most Tcp/Ip hosts respond once the connection is established.


Display this dialog box at connect time

If you check this box, the Admittance Data dialog will be presented whenever this profile is started.

This is designed to be used with a general-purpose Session profile which provides semi-automated connections by maintaining the base parameters while letting you change others.

For instance, you could have a general-purpose Tcp/Ip connection which set non-changing parameters, such as

Telnet port #, and would use this dialog to provide the IP address.


Runtime Admittance - OK
Runtime Admittance Data - OK

Press this pushbutton to initiate the connection process.  A connect dialog will be presented if the connection takes more than a second or two to complete.


Admittance Data - Save

Press this pushbutton to save any changed Admittance Data to the current session object name.


Admittance Data - Save as

Press this pushbutton to save the current Admittance data to a new session object name.


Modem

Select a modem from the modem list.

The modem list is built from the entries in the MODEMS database file.  When a modem list entry is selected, the baud rate and communications parameters fields of this dialog will be updated with the data from the SET record of the selected modem entry in the MODEMS database file.  If the selected modem entry does not contain a SET record, the baud rate and communications parameters fields will be set from the default values defined in the NETINFO file or specified during execution of the TCPSETUP configuration program.  These fields may be modified but if alternate settings are often required, it is recommended that either the MODEMS database file entry be changed or one or more new MODEMS database file entries be added.


Baud Rate

Select the desired communications port baud rate from the list of supported values.

If this field is modified often from either the SET record value or the default value, it is recommended that either the MODEMS database file entry be changed or one or more new MODEMS database file entries be added.


Data Bits, Stop Bits, Parity

Select the desired combined communications port data bits, stop bits and parity from the list of supported values.

If this field is modified often from either the SET record value or the default value, it is recommended that either the MODEMS database file entry be changed or one or more new MODEMS database file entries be added.


Number to Dial
SLIP Dial Parameters, Number to Dial

Enter the phone number of the Tcp/Ip capable system or Tcp/Ip network in the Number to Dial field.

If the phone number is available as an entry in the "Phone Numbers List" and it is selected from this list, the Number to Dial field will be updated from the selected entry in the PHONES database file.

When the Number to Dial is entered directly into this field, the advanced capabilities and benefits of batch command execution can not be utilized.

If the Number to dial is entered directly into the dialog Number to Dial field and it is a frequently used number, it is recommended that this number be added to the PHONES database file as a new entry.


Phone Numbers
SLIP Dial Parameters, Phone Numbers

Select the name of the entry containing the number to dial from this Phone Numbers list.

The Phone Numbers list is built from the entries in the PHONES database file.  When a Phone Numbers list entry is selected, the Number to Dial field of this dialog will be updated with the data from that PHONES database file entry.


Wait for Carrier Timeout

This field allows the specification of the maximum time interval that a dial operation should take between the initiation of the dial operation and the detection of a carrier signal.    Enter a value  between 1 and 255 seconds, inclusive.


Execute batch Commands Timeout

This field allows the specification of the maximum time interval that a dial operation should take between the detection of a carrier signal and the execution of the last batch command that specifies a receive string for the selected entry in the PHONES database file.  Enter a value of between 1 and 255 seconds, inclusive.

The value of this field is ignored during a dial operation if the Number to Dial was entered manually and not resolved from a PHONES database file entry or the  selected PHONES database file entry does not contain any batch commands that specify a receive string.


Block Size

Normally, telnet data is transmitted as it becomes available in as large as possible data blocks, limited by the underlying Tcp/Ip transport block size.  However, since Tcp/Ip terminal communications is often just an alternate communications layer which uses the same buffering mechanisms as ordinary terminal traffic, some terminal protocol converters and/or hosts are limited in how much data can be received in a single block.  This option allows specification of the maximum telnet data transmitted in a single block.  Enter a value of between 16 and 1024 (bytes), inclusive.


Block Delay
Inter-Block Delay

Normally, telnet data is transmitted as it becomes available in as large as possible data blocks, limited by the underlying Tcp/Ip transport block size.  However, since Tcp/Ip terminal communications is often just an alternate communications layer which uses the same buffering mechanisms as ordinary terminal traffic, some protocol converters and/or hosts are limited in how quickly successive blocks of data can be received.  This option allows specification of the minimum amount of time which will elapse between successive telnet transmits from the terminal.. Enter a value between 0 and 1000 (milliseconds), inclusive.


Receive Data Mask
Mask Receive Data to 7bits

Telnet data is, by default, 8 bits wide.  However, many terminal emulations require that the received data be only 7 bits wide.  In most instances, the data received on a telnet connection will conform to the requirements of the terminal.  However, when protocol converters are used in the route between the terminal and the host, sometimes the 8th bit will be randomly set, causing the terminal to act unreliably.  This option specifies the valid data width of each received byte.  Check this option if data is to be masked to 7 bits.


Strip null following received carriage return

Telnet conventions require that a carriage return character that signifies an end-of-line must be followed by either a null or a line feed.  In most cases, the inserted nulls will cause no problems and aid in the interpretation of the received data stream.  Sometimes, however, the nulls get inserted after carriage return characters which are not really end-of-line indicators; an example of this is terminals that use binary arguments for cursor positioning.  In this case, the null causes erratic terminal behavior.

If you experience erratic terminal behavior, check this box.  In most cases, eliminating the null after received carriage return characters will have no effect on other aspects of terminal operations.


Do not add null after transmitted carriage return

Telnet conventions require that a carriage return character that signifies an end-of-line must be followed by either a null or a line feed.  In most cases, the inserted nulls will cause no problems, and they aid in the interpretation of the received data stream.  Sometimes, however, host computer applications will complain about receiving nulls following carriage returns.

If you experience problems with host applications that appear to be associated with null insertion, check this box.  In most cases, eliminating the null after transmitted carriage return characters will have no effect on other aspects of host computer operations.


SLIP Configuration Admittance Data

This dialog allows you to specify the connection parameters for the Tcp/Ip connection.  The Phone number, IP address, telnet port number, and initial handshake transmission may be specified.

The initial value of the "Phone Number" field is derived from the phone number entered into the phone number field of the connection path Dial Parameters dialog.  If the value of this phone number field in the admittance data is changed it will override any value that is entered into the connection path Dial Parameters dialog field.  At connect time, the PHONES file will be searched in order to find an entry containing this phone number in order that any associated and appropriate batch commands may be executed.

Normally, the only field which requires input is the IP address field.  The telnet port number should be left with the "Use Default" checkbox checked unless you know that an alternate number should be used; this will cause the connection to be initiated on the default port number of 23.  The "Handshake Transmission" is normally left blank,  as most Tcp/Ip hosts respond once the connection is established.

If you wish to modify any of the parameters at the time the connection is initiated, use the checkbox "Display this dialog box at connect time".  Checking the field will cause this dialog to be presented when the runtime session is started so that the connection parameters may be changed before the connection is initiated.

To save the connection information under the current name, use the "Save" pushbutton.  To specify a new name, use the "Save as" pushbutton.


SLIP Runtime Admittance Data

This dialog allows you to modify the preset connection parameters for the Tcp/Ip connection.  The Phone number, IP address, telnet port number, and initial handshake transmission may be modified.

If the value of this "Phone Number" field in the admittance data is changed it will override any value that is entered into the connection path Dial Parameters dialog field.  At connect time, the PHONES file will be searched in order to find an entry containing this phone number in order that any associated and appropriate batch commands may be executed.

Normally, the only field which requires change is the IP address field.  The telnet port number should be left with the "Use Default" checkbox checked unless you know that an alternate number should be used; this will cause the connection to be initiated on the default port number of 23.  The "Handshake Transmission" is normally left blank,  as most Tcp/Ip hosts respond once the connection is established.

This dialog is presented because the checkbox "Display this dialog box at connect time" was checked in the admittance data for this session.  You may change the setting at this time if you wish, and after pressing "Save" or "Save as", the dialog will not be presented on subsequent executions of this session profile.

To initiate the connection without updating the saved profile information, press "OK".  To save the connection information under the current name, use the "Save" pushbutton.  To specify a new name, use the "Save as" pushbutton.  To cancel this session, use "Cancel".


SLIP Admittance Data, Phone Number

Enter the phone number of the Tcp/Ip capable system or Tcp/Ip network in the phone number field.

If this field is left blank, the phone number entered into the phone number field of the Dial Parameters dialog will be used.  If this field is specified, it's value will be used instead of any value entered into the phone number field of the Dial Parameters dialog.


SLIP Connection Parameters

This dialog is displayed during the SLIP connection process if the phone number specified in the SLIP Admittance Data  (or Dial Parameters dialog) does not have an entry in the PHONES database file or the entry in the PHONES database file does not have any associated batch commands.  This dialog allows certiain Tcp/Ip parameters to be defined or modified.

Local PC's IP Address

Domain Name

1st Name Server's IP Address

2nd Name Server's IP Address

Update NETINFO File


Local PC's IP Address

This field is used to specify the local IP address that is to be used for the current session.  The initial displayed value is obtained from the IPADDRESS record of the NETINFO file and the purpose of this field is cater to those Tcp/Ip networks that dynamically allocate an IP address that will be differnet each time that network is accessed.  A dynamically allocated IP address will be sent within a text string sent by the Tcp/Ip network and should be displayed on the terminal emulation screen.  This value must be entered into this dialog field so that the local Tcp/Ip environment may be correctly configured.


Domain Name

This field is used to define the name of the domain to which this PC belongs.  In conjunction with the "Name Server IP Addresses", this name allows access to a mechanism whereby destination IP addresses can be resolved by name rather than having to be specified in decimal dotted notation.  The alternative mechanism for name resolution is to build a local HOSTS database file that resolves host names to ip addresses.  The initial displayed value is obtained from the DOMAIN record of the NETINFO file and a value only needs to be entered into this dialog field if destination addresses will be specified as names rather than IP addresses.

1st Name Server's IP Address

2nd Name Server's IP Address


1st Name Server's IP Address

This field is used to define the IP address of the first name server that will be accessed when a destination host name must be resolved to an IP address and that host name can not be resolved by accessing the local HOSTS database file.

Domain Name


2nd Name Server's IP Address

This field is used to define the IP address of the second name server that will be accessed when a destination host name must be resolved to an IP address and that host name can not be resolved by accessing the local HOSTS database file or the 1st Name Server's Ip Address.

Domain Name


Update NETINFO file

This field id used to define whether the preceding field values are to be used to update those values recorded in the NETINFO file.  If the values are not expected to change regularly, it is recommened that this checkbox field be checked.

The following record in the NETINFO file will be updated:-

IPADDRESS=

DOMAIN=

NSIPADDRESS=

NS2IPADDRESS=