Route Strings
A route string describes the stations of a connection required between two hosts through one or more SAProuters. Each of these SAProuters checks its route permission table to see whether the connection between its predecessor and successor is allowed, and if it is, sets the connection up.
A route string has the syntax:
(/H/host/S/service/W/pass)*
A route string contains a substring for each SAProuter and for the target server. Each substring contains the information required by SAProuter to set up a connection in the route: the host name, the port name, and the password, if one was given.
A route string can contain any number of “Substrings”.
A SAProuter always checks only the previous host name or the previous IP address and the next substring (/H/.../S/.../W/..) for host name or IP address, service and password. The last substring does not contain a password, since there is no successor in the route.
If the /S/ section is missing, the default port number of the SAProuter is used. If the /W/ section is missing, a password is not used.
| /H/ | indicates the host name |
| /S/ | Specifis the service (port). This information is optional. The default value is 3299. |
| /W/ | Inicates the password for the connection between the predecessor and successor on the route. This information is optional. The default is "" (no password). |
Note that the host name must be at least two characters long.
H, S, and W must be uppercase!
In earlier Releases (<4.0A), the password entry was made one substring later and with the letter /P/.
New: /H/saprouter/W/pass/H/targetserver
Old: /H/saprouter/H/targetserver/P/pass
(Here pass is the password which is checked by the SAProuter on host saprouter to set up or prohibit the connection from the source host to the target host.)
Due to downward compatibility, the old password entry form is still possible.
Route strings are best illustrated by an example.
Example
The graphic above shows an example of a connection between SAP and a customer system.
In this example, an SAP service employee working on sappc wants to log on to a customer application server yourapp, which provides the service sapsrv. The SAP service employee logs on to the SAP system, and through the SAProuter on sap_rout and the customer's SAProuter your_rout sets up a connection between sappc and yourapp. your_rout requires the pass_to_app password for connections withyourapp.
The associated route string looks like:
/H/sap_rout/H/your_rout/W/pass_to_app/H/yourapp/S/sapsrv
This route string is interpreted by the SAProuters involved in the route as follows:
|
Host/address |
Service/port |
Password |
|---|---|---|---|
Substring 1 |
/H/sap_rout |
/S/<default> |
<no password> |
Substring 2 |
/H/your_rout |
/S/<default> |
/W/pass_to_app |
Substring 3 |
/H/yourapp |
/S/sapsrv |
|
The connection from sappc to the application server is set up in the following steps:
- sappc (front end):
Sets up the connection to SAProuter sap_rout according to substring 1 and relays the route information.
- sap_rout (SAProuter on SAP side):
Uses the route permission table to check whether route sappc zu your_rout 3299 is allowed, sets up the connection to the customer SAProuter on host your_rout, and passes substring 2 and 3.
- your_rout (SAProuter on customer side):
Checks whether route sap_rout to yourapp, sapsrv is permitted. Password pass_to_app is also checked. SAProuter then sets up the connection to the application server.