IPX/SPX Programming Manual

Addressing
HP NonStop IPX/SPX Programming Manual—528022-001
2-5
Supported NetWare Protocols
The NonStop IPX/SPX subsystem provides a socket interface to the SPXII and IPX
protocols. For more information, see Socket Interface to NonStop IPX/SPX on
page 2-8.
IPX uses the MAC protocol to transmit packets from one node to another. A MAC
header consists of a source node address and a destination node address. The node
address is a 6-byte number that is usually assigned by the LAN adapter vendor.
SPXII
The SPXII protocol provides a connection-oriented service, reliable to the extent that it
provides proper packet sequencing and retransmissions. It tracks data transmissions
by sending acknowledgment requests to the destination of the transmissions. If there is
no response within a specified time, SPXII retransmits the data. When no positive
acknowledgment returns after a certain number of retransmissions, SPXII assumes
that there is a failure in the connection and the connection is closed. SPXII permits the
use of a checksum, which you can enable or disable using the setsockopt or
setsockopt_nw routines described in Section 5, Library Routines.
The SPXII packet header is 12 bytes long. Figure 2-4 shows the format of the packet
header.
Table 2-2. IPX Socket Number Usage
Socket Numbers (Hexadecimal) Use
0x0002 Xecho (debugging tool)
0x0451 NCP
0x0452 SAP
Table 2-3. SPXII Socket Number Usage
Socket Numbers (Hexadecimal) Use
0x4000 - 0x4FFF Dynamic sockets used by SPXII for application
binds
0x7000 - 0x70FF TELSERV listener
0x7100 - 0x71FF ODBC listener
0x7200 - 0x72FF RSC listener.
0x8000 - 0xFFFF Static sockets assigned by Novell
0x86C0 - 0x86CB Reserved for HP use