APPN Add Connection Network

This option allows you to configure APPN Connection Network parameters.

When nodes are attached to a shared-access transport facility (SATF), any-to-any connectivity is possible. This any-to-any connectivity allows direct connections between any two nodes, eliminating routing through intermediate network nodes and the corresponding data traversing the SATF multiple times. To achieve this direct connectivity, however, TGs must be defined on each node for all the other possible partners.

Defining connections between all possible pairs of nodes attached to the SATF results in a large number of definitions (increasing on the order of the square of the number of nodes involved) and also a large number of topology database updates (TDUs) flowing in the APPN network. To alleviate these problems, APPN allows nodes to become members of a connection network to represent their attachment to an SATF. Session traffic between two nodes that have been defined as members of a connection network can be routed directly, without passing through a network node (achieves direct connectivity). To become a member of a connection network, an APPN node's port must be "attached" to a Connection Network by defining a connection network interface. When the port is defined, a Connection Network TG is created by the APPN component to identify the direct connection from the port to the SATF (i.e. the connection network). This TG is not a conventional TG as in the case of defined link stations, but rather represents the connection to the Connection Network in the topology database. TGs for end nodes are not contained in the network topology database, but are contained in the node's local topology database. TDUs do not flow through the network when a connection is established through a Connection Network or when an end node is made a member of a Connection Network.

Because the connectivity is represented by a TG from a given node to a Connection Network, normal topology and routing services (TRS) can be used for the network node server to calculate the direct path between any two nodes attached to the SATF (with TGs to the same Connection Network). DLC signaling information is returned from the destination node during the normal locate process to enable the origin node to establish a connection directly to the destination node.

Therefore, to achieve direct connectivity on an SATF, instead of each node on the SATF being defined (or connected) to each other, each node is connected to a Connection Network. The Connection Network is often visualized as a virtual node on the SATF to which all other nodes are attached. This model is frequently used and, in fact, the term Virtual Routing Node (VRN) is often interchanged with the term Connection Network.

Answer the following questions:

  1. Fully-qualified Connection network name (required for each connection network defined)

    This parameter specifies the fully-qualified name of the connection network being defined on this router network node. Since this name becomes the CP name of the virtual routing node (VRN), the name must be unique among all CP and LU names in the APPN network (same as in the local Control Point Name).

    All nodes that are members of a given connection network must use the same VRN Name.

    The fully-qualified VRN Name (CP name of VRN) has the form:

    Valid Values:

    A string of 1 to 8 characters :

    An existing connection network of which this node desires to become a member, named using the special characters @, $, and # from the character set A, continues to be supported; however, these characters should not be used for new connection network names.

    Default Value: None

  2. Port type (required)

    This parameter specifies the type of ports providing connectivity to the SATF for the connection network being defined. A given connection network only supports one type of port with one set of characteristics.

    Valid Values: Token-ring, Ethernet, Frame Relay BAN, ATM

    Default Value: None

  3. Select the Submit button.

  4. Port name (required)

    This parameter specifies the name of a port providing connectivity to the shared access transport facility (SATF) for the connection network being defined.

    All ports defined for a given connection network must be the same type and have the same characteristics.

    Valid Values: Name of port on which APPN routing has been enabled.

    Default Value: None

Enter the following Connection Network configuration for ATM information:

  1. Port name (required)

    This parameter specifies the name of a port providing connectivity to the shared access transport facility (SATF) for the connection network being defined.

    All ports defined for a given connection network must be the same type and have the same characteristics.

    Valid Values: Name of port on which APPN routing has been enabled.

    Default Value: None

  2. Fully qualified connection network name

    This parameter specifies the fully qualified CN name to which this TG is defined.

    Valid Values:

    A string of 3 to 17 characters in the form of netID.CNname , where :

    Each name must conform to the following rules:

    Default Value: None

  3. Connection network TG number

    This parameter specifies the TG number uniquely identifying this connection from the local port to the CN. The CN name and TG number pair must be unique.

    Valid Values: 1 - 239

    Default Value: None

  4. Limited Resource

    This parameter indicates if this TG should be brought down when not in use by session traffic.

    Valid Values: Yes or No

    Default Value: Yes

  5. Limited Resource Timer

    This parameter indicates the time limit after which this CN TG should be brought down when not in use by session traffic.

    Valid Values: 1 - 2160000 seconds

    Default Value: 180 seconds

  6. LDLC retry count

    This parameter is used in conjunction with the LDLC timer period to provide reliable delivery of XIDs. The retry count is initialized when a command or request is first transmitted over the link. If the LDLC timer period expires before a response is received, the command or request is retransmitted, the retry count is decremented, and the LDLC timer period is restarted. If the timer expires with the retry count at 0, the link is assumed to be inoperative.

    Valid Values: 1 - 255

    Default Value: 3

  7. LDLC Timer Period

    This parameter specifies the timer period used with the LDLC retry count.

    Valid Values: 1 - 255 seconds

    Default Value: 1 second

  8. Broadband Bearer Class

    This parameter specifies the bearer class requested from the ATM network. The classes are defined:

    Valid Values: Class_A, Class_C, Class_X

    Default Value: Class_X

  9. Shareable Regular Network traffic

    This parameter specifies whether traffic on this connection network TG can be routed on an ATM VC set up for a a regular TG or another CN TG.

    Valid Values: Yes, No

    Default Value: Yes, if this is a Best Effort CN. No, otherwise.

  10. Shareable other protocol traffic

    This parameter specifies whether the ATM VC established for this CN TG may be shared with other higher level protocols in the router.

    Valid Values: Yes, No

    Default Value: No

  11. Forward Peak Cell Rate

    This parameter indicates an upper bound on the cell transmission rate.

    Valid Values: 1 - 85% of line speed

    Default Value: Taken from the port definition

  12. Forward Sustained Cell Rate

    This parameter indicates an upper bound on the average cell transmission rate.

    Valid Values: 1 - 85% of line speed

    Default Value: Taken from the port definition

  13. Forward Tagging

    This parameter indicates that cells that are nonconforming to cell loss priority 0 traffic specification but are conforming to cell loss priority 1 traffic specification are marked and allowed into the ATM network.

    Valid Values: Yes, No

    Default Value: Yes

  14. QOS

    This parameter indicates which class of service is provided to an ATM virtual connection.

    Valid Values:

    CLASS_0, CLASS_1, CLASS_2, CLASS_3, CLASS_4, where:

    Default Value: CLASS_3

Enter the following information to modify TG characteristics:

  1. Cost per connect time

    This parameter expresses the relative cost of maintaining a connection over the associated TG. The units are user-defined and are typically based on the applicable tariffs of the transmission facility being used. The assigned values should reflect the actual expense of maintaining a connection over the TG relative to all other TGs in the network. A value of zero means that connections over the TG may be made at no additional cost (as in the case of many nonswitched facilities). Higher values represent higher costs.

    Valid Values: 0 - 255

    Default Value: 0

  2. Cost per byte

    This parameter expresses the relative cost of transmitting a byte over the associated TG. The units are user-defined and the assigned value should reflect the actual expenses incurred for transmitting over the TG relative to all other TGs in the network. A value of zero means that bytes may be transmitted over the TG at no additional cost. Higher values represent higher costs.

    Valid Values: 0 to 255

    Default Value: 0

  3. Security

    This parameter indicates the level of security protection associated with the TG. If security attributes other than the architecturally-defined ones are needed, one of the user-defined TG characteristics may be used to specify additional values.

    Valid Values:

    Default Value: Nonsecure

  4. Propagation delay

    This parameter specifies the approximate range for the length of time that it takes for a signal to propagate from one end of the TG to the other.

    Valid Values:

    Default Value: LAN

  5. Effective capacity

    This parameter specifies the effective maximum bit transmission rate for this connection network TG. Effective capacity specifies the maximum effective rate for both physical links and logical links.

    The effective capacity is encoded as a single-byte representation. The values X'00' and X' FF' are special cases used to denote minimum and maximum capacities. The range of the encoding is very large; however, only 256 values in the range may be specified.

    Valid Values: 2 hexadecimal digits in the range X'00' to X'FF'

    Default Value: X'75'

  6. First user-defined characteristic

    This parameter specifies the first of three additional characteristics that users may define to describe the TGs in the network. The default value of 128 allows a subset of TGs to be defined as more or less desirable than the rest without defining values for all TGs.

    Valid Values: 0 to 255

    Default Value: 128

  7. Second user-defined characteristic

    This parameter specifies the second of three additional characteristics that users may define to describe the TGs in the network. The default value of 128 allows a subset of TGs to be defined as more or less desirable than the rest without defining values for all TGs.

    Valid Values: 0 to 255

    Default Value: 128

  8. Third user-defined characteristic

    This parameter specifies the third of three additional characteristics that users may define to describe the TGs in the network. The default value of 128 allows a subset of TGs to be defined as more or less desirable than the rest without defining values for all TGs.

    Valid Values: 0 to 255

    Default Value: 128

Select the Submit button.