01 Logical Address
When PS is set to 01, that is, logical address, the host does not know or want to specify the actual physical route to the target endpoint. The host supplies a logical address for the endpoint host. In this case, all switches and the GRF must be programmed to route the connection.
The structure of the
Each switch or router has to look up the destination host’s logical address in its own tables and decide which of its output slots it will transfer the data to. In the table, there may be several output slots that could be used in the route.
PS set to 01 specifies that the first entry in the list of possible output ports must be used.
IP connection: An
After the IP connection is established, the data packets arriving at the GRF are routed to the appropriate output slot using the default or a
IP routing is discussed later in this chapter. Example 2 describes how to configure logical addresses.
10 Unused
This PS setting is not currently defined for use by the
11 Logical Address
The PS=11 setting is the same as the 01 setting, except that the switch or GRF can choose any output slot from a list of valid slots for this logical address. (Remember, with PS=01, the first port in the list is used.)
Again, the host does not know the route and instead supplies a logical address for the endpoint host. All switches and the GRF must be programmed to route the connection.