NetIPC 3000/XL Programmer's Reference Manual (5958-8600)

Chapter 3 75
NetIPC Intrinsics
IPCCONNECT
HP 3000 to HP 1000:
Checksumming — TCP checksumming will be enabled for both sides
of the connection if it is enabled by either side for HP 3000 to HP 1000
cross-system communication. On both the HP 3000 and HP 1000
checksumming can be enabled by setting bit 21 in the
flags parameter.
Send and receive sizes — The HP 3000 send and receive size range is
1 to 30,000 bytes. The HP 1000 send and receive size range is 1 to 8,000
bytes. Although the ranges are different, specify a send size within the
correct range. For example, if the HP 3000 node sends 16,000 bytes, the
HP 1000 node can call IPCRECV twice, receiving the first 8,000 bytes the
first time and the second 8,000 bytes the second time.
Note that the default send and receive sizes are different on different
HP systems. On the HP 3000, the default send and receive size is less
than or equal to 1,024 bytes. On the HP 1000 the default send and
receive size is 100 bytes.
HP 3000 to HP 9000:
Checksumming — When the ipcconnect() call is executed on the
HP 9000 node, checksumming is always enabled. Therefore
checksumming is always enabled for the HP 3000-to-HP 9000
connection.
Send and receive sizes — The HP 3000 send and receive size range is
1 to 30,000 bytes. The HP 9000 send and receive size range is 1 to
32,767 bytes. Although the ranges are different, cross-system
communication is not affected. If you specify a send or receive size, be
sure it is within the correct range for the respective system.
Note that the default send and receive sizes are different on different
HP systems. On the HP 3000, the default send and receive is less than
or equal to 1,024 bytes. On the HP 9000, the default send and receive
size is 100 bytes.
HP 3000 to PC NetIPC:
Checksumming — With PC NetIPC, the TCP checksum option cannot
be turned on. But if the HP 3000 requires it, the TCP checksum is in
effect on both sides of the connection.
Send and receive sizes — The HP 3000 send and receive size range is
1 to 30,000 bytes. The PC send and receive size range is 1 to 65,535
bytes. Although the ranges are different, cross-system communication
is not affected. For example, if the PC node sends 60,000 bytes, the
HP 3000 node can call IPCRECV twice, receiving the first 30,000 bytes
the first time and the second 30,000 bytes the second time.
Note that the default send and receive sizes are different on different
HP systems. On the HP 3000, the default send and receive size is less
than or equal to 1,024 bytes.