What are the IBM-supplied default classes of service?

Descriptions of the seven IBM-supplied APPN Classes of Service follow. These classes define seven generic types of session traffic. See the z/OS Communications Server: SNA Resource Definition Reference for samples.

#BATCH: An APPN COS for LU-LU sessions that specifies a general batch-oriented COS that uses low transmission priority, and for which high bandwidth and low cost are considered more important than short delay.
#BATCHSC: An APPN COS for LU-LU sessions that specifies a general batch-oriented COS that uses low transmission priority, and for which high bandwidth and low cost are considered more important than short delay. A minimum security level is required.
#CONNECT: An APPN COS for LU-LU sessions that provides connectivity at medium transmission priority.
CPSVCMG: An APPN COS for CP-CP sessions that is used for network flows. It provides connectivity at network transmission priority.
#INTER: An APPN COS for LU-LU sessions that specifies a general, interactive COS that uses high-transmission priority, and for which short delay is considered more important than high bandwidth and lost cost.
#INTERSC: An APPN COS for an LU-LU session that specifies a general, interactive COS that uses high-transmission priority, and for which short delay is considered more important than high bandwidth and lost cost. A minimal security level is required.
SNASVCMG: An APPN COS for LU-LU CNOS sessions that provides connectivity at network transmission priority.

Three sets of IBM-supplied classes of service are available. Each set contains the seven classes described previously. The three sets are:

COSAPPN

The definitions in the COSAPPN definition set are made up of 8-row LINEROW entries and 8-row NODEROW entries for all classes of service and are appropriate for most sessions. The LINEROW values for the #CONNECT class of service in COSAPPN are shown in Table 1.

Table 1. COSAPPN #CONNECT class of service LINEROW values
LINEROW	CAPACITY	COSTBYTE	COSTTIME	PDELAY	SECURITY	WEIGHT
1	4M MAXIMUM	0 0	0 0	MINIMUM NEGLIGIB	UNSECURE MAXIMUM	30
2	56000 MAXIMUM	0 0	0 0	MINIMUM TERRESTR	UNSECURE MAXIMUM	60
3	19200 MAXIMUM	0 0	0 0	MINIMUM TERRESTR	UNSECURE MAXIMUM	90
4	9600 MAXIMUM	0 0	0 0	MINIMUM TERRESTR	UNSECURE MAXIMUM	120
5	19200 MAXIMUM	0 0	0 0	MINIMUM PACKET	UNSECURE MAXIMUM	150
6	9600 MAXIMUM	0 128	0 128	MINIMUM PACKET	UNSECURE MAXIMUM	180
7	4800 MAXIMUM	0 196	0 196	MINIMUM MAXIMUM	UNSECURE MAXIMUM	210
8	MINIMUM MAXIMUM	0 255	0 255	MINIMUM MAXIMUM	UNSECURE MAXIMUM	240

.

ISTACST2

The definitions in the ISTACST2 definition set are made up of 12-row LINEROW entries and 8-row NODEROW entries for all classes of service except CPSVCMG and SNASVCMG, which are made up of 8-row LINEROW entries and 8-row NODEROW entries. These 12-row LINEROW entries enable z/OS® Communication Server to select an optimal route for a session. The greater number of entries provides optimal results when multiple connections with different TG characteristics (for example, channel-to-channel, token-ring network, FDDI LAN, and ATM) are used in the network.

The LINEROW values for the #CONNECT class of service in ISTACST2 are shown in Table 2.

Table 2. ISTACST2 #CONNECT class of service LINEROW values
LINEROW	CAPACITY	COSTBYTE	COSTTIME	PDELAY	SECURITY	WEIGHT
1	100M MAXIMUM	0 0	0 64	MINIMUM NEGLIGIB	UNSECURE MAXIMUM	20
2	10M MAXIMUM	0 0	0 64	MINIMUM NEGLIGIB	UNSECURE MAXIMUM	40
3	4M MAXIMUM	0 0	0 64	MINIMUM NEGLIGIB	UNSECURE MAXIMUM	60
4	10M MAXIMUM	0 0	0 64	MINIMUM TERRESTR	UNSECURE MAXIMUM	80
5	56000 MAXIMUM	0 0	0 64	MINIMUM TERRESTR	UNSECURE MAXIMUM	100
6	29K MAXIMUM	0 0	0 64	MINIMUM TERRESTR	UNSECURE MAXIMUM	120
7	100M MAXIMUM	0 128	0 128	MINIMUM TERRESTR	UNSECURE MAXIMUM	140
8	10M MAXIMUM	0 128	0 128	MINIMUM TERRESTR	UNSECURE MAXIMUM	160
9	56000 MAXIMUM	0 128	0 64	MINIMUM TERRESTR	UNSECURE MAXIMUM	180
10	29K MAXIMUM	0 128	0 128	MINIMUM PACKET	UNSECURE MAXIMUM	200
11	9600 MAXIMUM	0 0	0 64	MINIMUM PACKET	UNSECURE MAXIMUM	220
12	MINIMUM MAXIMUM	0 255	0 255	MINIMUM MAXIMUM	UNSECURE MAXIMUM	240

ISTACST3

The definitions in the ISTACST3 definition set are made up of 12-row LINEROW entries and 8-row NODEROW entries for all seven classes of service. The definitions enable z/OS Communications Server to select an optimal route for a session when connections in the network include connections with high speed link characteristics such as FICON®, Gigabit Ethernet, and HiperSockets™.

The LINEROW values for the #CONNECT class of service in ISTACST3 are shown in Table 3.

Table 3. ISTACST3 #CONNECT class of service LINEROW values
LINEROW	CAPACITY	COSTBYTE	COSTTIME	PDELAY	SECURITY	WEIGHT
1	10G MAXIMUM	0 0	0 64	MINIMUM NEGLIGIB	UNSECURE MAXIMUM	20
2	1G MAXIMUM	0 0	0 64	MINIMUM NEGLIGIB	UNSECURE MAXIMUM	40
3	100M MAXIMUM	0 0	0 64	MINIMUM NEGLIGIB	UNSECURE MAXIMUM	60
4	1G MAXIMUM	0 0	0 64	MINIMUM TERRESTR	UNSECURE MAXIMUM	80
5	25M MAXIMUM	0 0	0 64	MINIMUM TERRESTR	UNSECURE MAXIMUM	100
6	1M MAXIMUM	0 0	0 64	MINIMUM TERRESTR	UNSECURE MAXIMUM	120
7	10G MAXIMUM	0 128	0 128	MINIMUM TERRESTR	UNSECURE MAXIMUM	140
8	1G MAXIMUM	0 128	0 128	MINIMUM TERRESTR	UNSECURE MAXIMUM	160
9	16M MAXIMUM	0 128	0 64	MINIMUM TERRESTR	UNSECURE MAXIMUM	180
10	1M MAXIMUM	0 128	0 128	MINIMUM PACKET	UNSECURE MAXIMUM	200
11	64K MAXIMUM	0 0	0 64	MINIMUM PACKET	UNSECURE MAXIMUM	220
12	MINIMUM MAXIMUM	0 255	0 255	MINIMUM MAXIMUM	UNSECURE MAXIMUM	240

The definition sets COSAPPN, ISTACST2, and ISTACST3 are shipped in SYS1.ASAMPLIB. To use one of these sets, you must copy it into SYS1.VTAMLST when you install z/OS Communication Server, and then activate the member in which the definitions reside. You can copy multiple sets of definitions into SYS1.VTAMLST, but you can have only one set active at any time.

The COSAPPN definition set is automatically activated when z/OS Communication Server is initialized. If you choose to use ISTACST2 or ISTACST3, use the VARY ACT command to activate it, or place the ISTACST2 or ISTACST3 member in the configuration list to automatically activate it when z/OS Communication Server is initialized. You can rename the IBM-supplied sets of definitions so that ISTACST2 or ISTACST3 is named COSAPPN, and COSAPPN is either not used or is renamed to something else. Renaming the definition sets in this way causes the set of definitions with 12-row LINEROW entries to be automatically activated when z/OS Communication Server is initialized.

Guideline: If you activate a set of definitions with 12-row LINEROW entries, you should have the same set of definitions with 12-row LINEROW entries activated on each network node in the network for optimal routing in networks that include ATM native or high-speed connections.

Not all HPR APPN products support COS definitions with 12-row LINEROW entries. This could affect your ability to optimally use native ATM connections or high speed connections among the nodes in your network. Consult technical representatives for the HPR APPN products in your network to determine if those products support COS definitions with 12-row LINEROW entries.

If you use COS definitions with 12-row LINEROW entries, routes selected for sessions could be different than those selected when you use COS definitions with 8-row LINEROW entries.