A port represents the local end of a communications link as a unique access point in the network. Each port is associated with a specific link protocol, which can be any of the following:
You can configure more than one port that uses a particular link protocol. In general, a port corresponds to a single physical access point such as an adapter card, but some link protocols (such as token ring) enable you to define multiple ports for a single adapter. The different ports are distinguished by addresses (such as the SAP number).
When you use the Motif administration program to define a port for a particular link protocol, CS/AIX automatically defines a DLC for the port if a DLC of that type has not already been defined. For command-line configuration, you must define the port and DLC using different commands.
In an APPN network using token ring, Ethernet, FDDI, or IP link protocols, you can also use the SAP Configuration dialog to indicate that the port is part of a connection network.
If you are using SNA gateway, you can define a template that is used to generate definitions for implicit link stations (link stations that are not explicitly configured). Implicit link stations can support downstream LUs. If implicit PU fields are modified while the port is active, the changes affect any implicit link station instances generated after the change.
To configure a port, connection network, and DLC, use one of the following methods:
To configure a port:
define_type_port
In these commands, type indicates the link protocol type (sdlc, tr, ethernet, fddi, qllc, channel, mpc, mpc_plus, ip).
To configure a connection network:
define_cn
Advanced port configuration parameters provide control over BTU size, the number of active links permitted, generation of implicit downstream LUs, and settings for dynamic link stations.
The following parameters are required for port configuration. (When you use the Motif administration program, port configuration also supplies information about the DLC and enables you to assign a port to a connection network.)
A number that identifies the adapter card to use, if you have more than one card of the same type in this computer.
Set this to the value given in the numeric part of the device name. For example, if you have a token ring device called tok3, then set this parameter to 3.
The number of the port to be used, if the adapter card can support more than one port. The range of valid port numbers is from 0 to the number of ports supported by the adapter card minus one. For the first port on the adapter card, enter 0.
This field applies only if the adapter card can support more than one port.
The following sections describe additional port parameters that are specific to the link type. No additional port parameters are required for QLLC or Channel.
For a nonprimary port (as indicated by the Link role field), you also need to configure the poll address (for outgoing calls, that address is configured on the link station). The poll address is a one-byte address (C1 by default) that needs to match the poll address configured at the remote link station. When active, the port responds to frames sent with this poll address.
For a primary port, you do not need to configure a poll address; the port uses the poll address specified by the remote link station on the incoming call. For other types of ports, the poll address is configured on each link station.
Use one of the following values for this field:
You can use this setting for a peer link, but be aware that negotiating the role causes a short delay when the link is activated.
Use this setting when you want to configure several link stations from the local node to different remote nodes (for example, for links to downstream nodes). Each of these other nodes must be configured as secondary, and you must be using a leased line.
If you configure a port for a switched incoming or leased line, you also need to configure the following items:
This value must match the encoding scheme used by the modem at the remote end of the link. If you set this field incorrectly, you will find that the frames being received are all discarded and do not appear in any trace.
On a VTAM host, this is the NRZI= setting in the LINE/GROUP definition.
For switched outgoing ports, you configure the line encoding and duplex settings on each link station (see Defining Link Stations) instead of on the port.
| Note: | Some adapter cards do not support all the physical link types listed. Consult the documentation for your modem and adapter card for more details. |
If you configure a switched incoming port with a physical link type of Smartmodem or V.25bis, you need to configure the following:
For an explanation of the contents of the dial string, refer to your modem's documentation.
For switched outgoing ports, the dial string is configured on each link station. For leased ports, or for ports using other physical link types, this field does not apply.
Consult your SNA network planner if you do not know how to configure any of these parameters.
The SAP number must be a multiple of 2.
If you do not know what value to enter for this field, contact your SNA network planner.
This field applies only if the local node is not a LEN node, because LEN nodes cannot use connection networks.
Specify the same CN name on all nodes on the connection network.
Whether the network is a standard Ethernet network or an IEEE 802.3 network.
After performing the port configuration, continue with the following configuration tasks: