the connection. This can be done with the DIAL command or it can be invoked from the "prodial" program installed on one of the UNIX systems on the network. This also allows connections to be scheduled by using the UNIX cron scheduler to call pmdial.

DESTINATION - The Internet Address of the system at the remote end of the dial-up connection. A valid IP address using standard dot notation should be entered as the value.

NETMASK - The netmask of the system at the remote end of the dial-up connection, A valid netmask using standard dot notation should be entered as the value.

ROUTING - This parameter determines whether, Routing Information Protocol (RIP) packets will be sent across the interface, allowing the remote system to manage and broadcast the current routing tables to its local network. When OFF, the PortMaster will listen on the interface for RIP packets, but will not broadcast any routing informatlon on the interface, VaLid values are ON or OFF,

IDLETIME - For Manual and On-Demand type locations this specifies the number of minutes the line should be idle (no network traffic to the remote site) before disconnecting the telephone connection. A value between 0 and 240 can be specified. If 0 is chosen, the connection will not time out.

MAXPORTS - The number of dial-out ports the PortMaster can use for this network connection. If 0 is selected dialing to this location will be disabled. If more than I is selected the PortMaster will use the "High Water Mark" to decide when to open and dial additional lines. If more than one line is open to the remote


location the PortMaster w/wiIl automatically use load balancing to achieve the maximum throughput of all lines combined. If multiple lines are open the "Idle Timeout" value will be used to decide when to disconnect unneeded lines, A value between 0 and l0 may be entered.

HIGH WATER - The number of bytes of queued network traffic required to open an additional dial-out line to the remote site, This value is only used when the "Maximum Ports" is greater than I and there are available modems on the PortMaster. Setting a very small number will cause the PortMaster to quickly use all of the ports specified in "Maximum Ports", Generally, interactive terminal traffic has no more than a few hundred bytes queued at any one time. However, file transfers (ie. ftp) will queue several thousand bytes. These size differences should be used when deciding what number to use for the High Water Mark. A value between 0 and 65535 may be entered,

GROUP - The modem pool group to which this location is assigned. Only modem ports which are configured with this Group Number will be available for dial-out to this location. This can be used to reserve modems for dial-up to specific locations or to differentiate different types of modems which would be compatible with the remote location, A value between 0 and 100 ma), be entered.

SCRIPT - The dial command script is used to issue commands to the modem (or other similar equipment) to dial the correct number and establish the link. In addition, this script is used for authentication (password security) at the remote site. Three values must be entered with the SCRIPT parameter. The syntax is:

SET location_name SCRIPT lineno send reply

Where line_no is a number between 1 and 6. send is a string of up to 30 characters surrounded by double quotes, reply is a string of up to 30 characters surrounded by double quotes. Each line_no represents one send-reply combination.

Each "Send" string is issued out of the PortMaster serial port to the modem or remote computer. Each "Reply" string is used by the PortMaster to verify that the previous 'Send" string was properly received by the modem or remote computer and the PortMaster should transmit the next "Send" string.

Any printing ASCII character can be placed in the send or reply strings. In addition, the following special characters are available:

\r - This is replaced by the ASCII carriage return,

\n - This is replaced by the ASCII line feed.

\OXX - This is replaced by the octal digit in the XX.

\\ - This is replaced by the single backslash (\).

Generally Send strings would end with the "\r" character,

It is important that the last entry in the Dial Command Script be a Reply string which indicates that the remote location is ready to begin receiving network packets. This is used to activate the TCP/IP protocol coming from the PortMaster. When connecting to a remote PortMaster the final reply string to look for


should be "SLflP". For other products, consult that
vendors users manual

 The following Dial Command Script is an example of how to establish a connection between two PortMasters which have modems supporting the "AT" dial

 command syntax:

 Send

 ATDT18005551212\r \r my_location_name\r my~password\r

 Reply

 CONNECT login: ssword: SL/IP

 The "18005551212" would be replaced by the actual telephone number of the remote modem. "my_location_name" would be replaced by the actual user name for your location. "my~0assword" would be replaced by the actual password set up at the remote site which corresponds to the user name.

 SHOW Command

 List a summary of the locations table or the detail of a specific location.

 The syntax for the show command is:

 SHOW TABLE LOCATION - to display a summary of the location table.

 SHO%V location_name - where location_name is the name of a previously created location. This will display all of the configuration information for the location.

 
SAVE Command

 Save Locations into the permanent PortMaster configuration. The syntax is:

 SAVE LOCATION

 Managing the Passwords Table

 The Passwords Table provides a security and network parameter initialization scheme for locations or individual computers dialing into the Portmaster to establish remote network connections. Modem ports configured to accept Slip Dial-in sessions initially prompt for a login user name. After receiving the login name, the PortMaster checks the name against the list of names in the local Passwords Table. If found, the Portmaster assumes that this connection will be for a dial-in network session and initiates password authentication of the remote system, If successfully validated (the password received matches the password stored in the Passwords Table} the PortMaster responds with the message:

 SL/IP session from local (149.198.9.1) to remote beginning ....

The PortMaster then enables the SLIP network interface and any associated routing information as indicated in the Passwords Table. Finally it begins accepting and sending IP packets over the connection.

 1. the login name does not match an entry in the Passwords Table and the port is configured to support User Logins it automatically forwards the session to the designated host on the local network for password authentication.


 Four commands have been established /or managing the local passwords table:

 ADD Command - adds entries to the local passwords table.

 DELETE Command - deletes entries from the Iocal passwords table.

 SHOW Command - the entries in the local passwords table.

 SAVE Command - saves the passwords in the permanent configuration.

 ADD Command - Add an entry to the local passwords table, The syntax is:

 ADD password name password destination netmask [rip] Where:

 name - is the login name of the remote system requesting a SLIP dial-in session. This name can be up to 8 characters in length and is the user name to be supplied at the 'login:" prompt from the PortMaster. If the PortMaster is configured to support User Logins in addition to SLIP sessions, the SLIP login name must not conflict with a login name on the designated login host on the network.

password - is the password for the SLIP login name, This is a

 destination - The Internet Address or a valid host name of tile system at the remote end of the dial-up
connection.

netmask - is the netmask of the system at the remote end of the dial-up connection.

rip - When rip is specified, Routing Information Protocol (RIP) packets will be sent across the interface, allowing the remote system to manage and broadcast the current routing tables to its local network. Otherwise, the PortMaster will listen on the interface for RIP packets, but will not broadcast any routing information on the interface.

 DELETE Command

Delete an entry from the local passwords table. The syntax is: DELETE password name

Where:
name - is the login name of an existing password entry.


SHOW Command


List the contents of the active passwords table.


The syntax for the show command is:

SHOW password

SAVE Command

gave passwords into the permanent PortMaster configuration. The syntax is:


SAVE password

Managing the Hosts Table

Each device attached to the Ethernet (with uses TCP/IP) is assigned a unique internet address. Internet addresses are four byte numerical values. To make it easier to remember


these values, most systems on the network support a way of aliasing the internet address to some unique and easy to remember name. This is done on UNIX Workstations in the /crc/hosts file. The PortMaster also supports the same capability by maintaining a local hosts table.


The PortMaster hosts table should be used when any of the ports are set to prompt the user for a host name on the network. This table is then consulted to determine the correct internet address of the host.

If the hostname specified by the user is not found in the hosts table, then the PortMaster will attempt to match the hostname using the Network Information Service (NIS), also known as 'YP". See the section "Setting Global Parameters" for more information on setting the YP server and YP domain.

Three commands have been established for managing the local hosts table:

ADD Command - adds entries to the local hosts table.

DELETE Command - deletes entries from the local hosts table.

SHOW Command - shows the entries in the local hosts table.

ADD Command

Add an entry to the local hosts table. The syntax is: ADD host internet_address hostname

Where:

internet_address - is a valid host internet address in the form:

XXX.XXX,XXX.XXX

where XXX is a decimal number between 0 and 255.

hostname - is a character string of printable characters,

DELETE Command

Delete an entry from the local hosts table. The syntax is:

DELETE host internetaddress

- OR -

DELETE host hostname

Where:

internetaddress - is a valid host internet address in the form:

XXX.XXX.XXX.XXX

where XXX is a decimal number between 0 and 255,


hostname - is a character string of printable characters.

SHOW Command

List the contents of the local hosts table.

The syntax for the show command is:

SHOW table hosts

Managing the Routes Table

The PortMaster Routes table is used when static network routes are required. Static routes are required when the user chooses not to run the Routing Information Protocol (RIP) on the PortMaster, or when hosts or networks attached to the PortMaster do not have the ability to run the RIP protocol. The static routing table contains three entries:


Administration

Destination - This is the host or network to which the PortMaster will be required to send packets.

Gateway - This is the directly connected host through which packets should be forwarded to reach the above destination.

Metric - This is a metric representing the cost of sending the packet through the above gateway. Generally metric is the HOP count to the remote network. This would be the number of gateways through which the packet must traverse to reach its destination.

Four commands have been established for managing the local
routes table:

ADD Command - adds entries to the local routes table.

DELETE Command - deletes entries from the local routes table.

SHOW Command - shows the dynamic and static routing entries for the local PortMaster.

SAVE Command - saves the static routes in the permanent configuration.

ADD Command

Add an entry~, to the local routes table. The syntax is:

ADD route destination gateway tilertlc

Where:

destination - is a valid host or network internet address in the form:

XXX.XXX.XXX .XXX

where XXX is a decimal number between 0 and 255.

gateway - is a valid host internet address in the form:
 
XXX.XXX.XXX.XXX

where XXX is a decimal number between 0 and 255. metric - is a number between 1 and 15.

DELETE Command

Delete an entry from the local routes table. The syntax is: DELETE route destination


Where:

destination - is a valid host internet address in the form:

XXX.XXX.XXX,XXX

where XXX is a decimal number between 0 and 255.

SHOW Command

List the contents of the active routes table,

The syntax for the show command is:

SHOW routes

SAVE Command

Save static routes into the permanent PortMaster configuration. The syntax is:

SAVE routes


On To Networking Primer