Transmission services profile

The transmission services profile identifies a predefined set of session-control requests that can be used in a session. Each profile represents a different set of session-control requests and other transmission services attributes. For a detailed description of the transmission services profiles, see SNA Formats The following profiles are available to the VTAM® application program and can be specified in the transmission services field (using the TSPROF operand of the MODEENT macroinstruction).

Bit setting 0123 4567: (Byte 2) Meaning
0000 0010: Transmission services profile 2 is to be used. (This profile applies only to LU type 0 3270 sessions.)
0000 0011: Transmission services profile 3 is to be used.
0000 0100: Transmission services profile 4 is to be used.
0000 0111: Transmission services profile 7 is to be used.

The session-control requests that apply to each of these profiles are shown in Table 1.

In this table:

Req: This request must be used. The required requests can be issued by VTAM on behalf of the application program.
Opt: This request can be used.
N/A: Not applicable. This request must not be used.

Table 1. Session-control requests for each transmission services profile
Session- control request	Profile 2	Profile 3	Profile 4	Profile 7
CLEAR	Opt	Opt	Opt	N/A
RQR	N/A	N/A	Opt	N/A
SDT	N/A	Req	Req	N/A
STSN	N/A	N/A	Opt	N/A

The function management usage field is used to supplement the protocol rules defined by the function management profile. The function management usage field is divided into three parts:

The primary logical unit protocols (specified with the PRIPROT operand of the MODEENT macroinstruction) apply to the primary end of the session.
The secondary logical unit protocols (specified with the SECPROT operand of the MODEENT macroinstruction) apply to the secondary end of the session.
The common logical unit protocols (specified with the COMPROT operand of the MODEENT macroinstruction) apply to both the primary and secondary ends of the session.

The 2 bytes describing the primary and secondary logical unit protocols have the same format; however, different bits can be on or off depending upon the protocol used and how it applies to the specific end of the session being described by the byte.

The format of the function management usage field is described in SNA Technical Overview and is also shown in Table 2 (see the primary, secondary, and common protocol fields). An overview of the use of many of the indicators in this field is given in Communicating with logical units. More detailed information about the function management usage field can be found in SNA Sessions Between Logical Units and SNA Concepts and Products