SAProuter

SAP GUI uses the TCP/IP protocol to connect to a SAP system.

A SAProuter can be used to allow SAP GUI to connect to SAP Systems in other networks segments, for example when the SAP System is on another subnet or behind a firewall.

To connect to a SAP System on another network, when setting up the parameters in SAP GUI to the SAP system, you will also need to define a “SAProuter String”.



A SAProuter string is a list of SAProuters that must be passed in order to reach the SAP System.
This string consists of hosts which is defined with a “H” and services which is defined with an “S”

• A host is the SAProuter to connect to.
• A service is the port in the SAProuter to connect to.
  

When a SAProuter receives a request to a port, it then forward the connection onto either another SAProuter or the SAP system.

Lets take an example. Let say the following SAProute string is defined.

/H/CustGateway/S/3299/H/SAPGateway/S/3299/H/SAPSystem/S/3201

What does this mean? Well if we break it up into services and hosts, we can see the following

/H/CustGateway/S/3299/H/SAPGateway/S/3299/H/SAPSystem/S/3201

1. Firsly SAP GUI tries to connect to a server called CustGateway (this could be an IP address) to port 3299
   
2. When CustGateway receives this request, it forwards it onto a server called SAPGateway to port 3299.


3. When SAPGateway received this request, it forwards onto a server called SAPSystem to port 3201

Some extra info:

All SAP GUI connections are made to the “Dispatcher” on a SAP system. The port number for the dispatcher always starts with 32 and consists of four digits. The last two digits are the instance number.

In the above example, we connect to port 3201, this means we are connecting to instance 01.