Destination Types 
Each destination has a connection-type field (Connection type), which tells the kind of system connection:
· R/2 connections (Type 2)
Type 2 entries specify R/2 systems. No further specification is required, i.e. when you create a type 2 entry, you only need to give the host name; all communications information is already stored in the sideinfo table in the SAP Gateway host. You can, however, specify logon information if desired.
Example entry name: K50
· ABAP connections (Type 3)
Type 3 entries specify ABAP systems. When you create a type 3 entry, you must give the host name and communications service. You can, however, specify logon information if desired. From Release 3.0 onwards, you can also specify the load-balancing option if desired.
You can specify an application server from the ABAP message server. The application server is then determined according to the load-balancing process. This applies both for RFCs between ABAP systems and external calls to ABAP systems.
Example entry name: K11
· Internal connections (Type I)
Type I entries specify ABAP systems connected to the same data base as the current system. These entries are pre-defined and cannot be modified. The entry names are the same as those used in the SAP Message Server (transaction SM51)
Example entry name: hs0010_K11_24
¡ hs0010=host name
¡ K11=system name (data base name)
¡ 24=TCP-service name
· Logical destinations (Type L)
Instead of specifying a system connection, type L (logical) entries refer to a physical destination. Type L destinations can also refer to other type L entries. A type L entry uses the information in the "referred-to" entry, and adds further information of its own. Typically, the "referred-to" entry gives the host information, and the type-L entry gives logon data. You can also set a user name, an explicit password, a logon language or an explicit client.
A type L entry can refer to other type L entries.
Example entry name: K11_SD or K11_01
¡ K11=name of RFCDES entry for ABAP system K11
¡ SD or 01: for the fields User='SD_INPUT' or Mandant='001'
· Connections via ABAP driver (Type X)
Type X entries specify systems where device drivers in ABAP have been specially installed. When you create a type X entry, you must give the name of the ABAP device driver.
· TCP/IP Connections (Type T)
Type T destinations are connections to external programs that use the RFC API to receive RFCs. The activation type can be either Start or Registration.
If it is Start, you must specify the host name and the pathname of the program to be started.
Activation Type Start
The communication method depends on how you select the program location:
¡ Explicit host
In this
case, the program is started either by the default gateway for the system or
by the explicitly specified gateway (gwrd) via remote shell.
Ensure that the computer with the gateway process can access the specified
computer by entering /etc/ping <host name>.
In order to be able to start a program on another computer using remote shell, the target system must fulfil certain conditions.
§ The user ID of the gateway process must exist and a file called.rhosts must also be present in the user's home diretory.
§ The file.rhosts must contain the name of the calling computer.
To check this, logon to the computer containing the gateway process with the appropriate user ID and enter the command remsh <host name> <program name>. The <host name> and <program name> must be the same as in SM59. (If you call an RFC server program without any parameters, the RfcAccept call always returns an error code (RFC_HANDLE_NULL) and the program terminates at once.)
¡ Application server
On choosing Application server and specifying your program, you can start the program from the SAP application server.
First, ensure that the program can be accessed from the SAP application server and that the SAP application server has the authorization to start the program.
To check this, logon with the user ID of the SAP application server (e.g. c11adm). If possible, change to the working directory of the SAP application server (/usr/sap/.../D.../work) and try to start the RFC server program manually from there. (If you call an RFC server program without any parameters, the RfcAccept call always returns an error code (RFC_HANDLE_NULL) and the program terminates at once.)
¡ Front-end workstation
On choosing Front-end workstation and specifying your program, you can start the program from the SAPGUI.
Ensure that you can access the program with SAPGUI.
Ensure that SAPGUI has the authorization to start the program.
To check this, simply call the RFC server program in your environment.
The function call can also be transactional (CALL FUNCTION... IN BACKGROUND TASK DESTINATION...).
Activation Type Registration
If the activation type is Registration, you have to identify a registered RFC program. With an SAP gateway, an RFC server program can be registered under this ID and then wait for RFC calls from different SAP Systems.
Example entry name: SERVER_EXEC
· Type M
Type M entries are asynchronous RFC connections to ABAP systems via CMC (protocol X.400).
· Type S
Type S corresponds to type 2, except that the destination is SNA or APPC.
HTTP connection to ext. Server (connection type G)
Select the connection you require. You can choose your logon procedure from the following options:
· No logon. The server program does not require you to enter a user and password.
· Basic Authentication. The server program requires you to enter a user and password. Basic Authentication is a standard HTTP authentication method. When the user logs on to the target system, a user ID and a password for authentication is provided. This information is then transmitted across the HTTP connection to the server, in the form of a base64 encoded string in a header variable.
· SSL Client Certificate. If you use client certificates for the authentication, the client authentication is made using the Secure Sockets Layer (SSL) protocol. In this instance, you also have to select the SSL client PSE of the SAP Web AS, which contains the certificate that is to be used for the authentication. The target system must treat the system that issues the client certificate of the SAP Web AS as a trusted system.
·
On the tab page
Logon/Security
you can also activate SSL, so that HTTPS
is used as a protocol (you must then make sure that the correct port is set
under Technical
Settings). You can
define which type of SSL client is used, in the security transaction STRUST.
(
Getting Started with
the Trust Manager, Trust
Manager).
As an additional protective measure, the field Authorization for Destination was introduced. We recommend that you specify a user and a password for the RFC destination.
HTTP connection to SAP system (connection type H)
Here you have a variety of options for authentication in the target system.
The settings found on the tab pages Technical Settings and Special Options are identical to those of connection type G. On the tab page Logon/Security, the connection type H has additional logon processes compared to connection type G. As for the external server, you can (de)activate SSL and specify an authorization.
Since the target system is an SAP system, as well as the user and password, you can also define the client and language which are to be used for logging on to the SAP system. If the checkbox Current User is activated, you still have to enter the relevant password.
The options available for the authentication are Basic Authentication, SAP Standard, SAP Trusted System and SSL Client Certificate.
· HTTP Basic Authentication: Logon using user and password.
· SAP Standard: This method uses a logon like the RFC logon processes. Here, the RFC Single Sign-On procedures within a system also apply. The logon takes place using the same SAP user (client, language and user name).
· SAP Trusted System: Trusted RFC logon to another SAP system (see: Trusted System: Trust Relationships Between SAP Systems).
· SSL Client Certificate: Using the SSL protocol, the logon can be made by using client certificates.
Maintaining Group Destinations