Internetwork Packet Exchange/Sequenced Packet Exchange


Internetwork Packet Exchange/Sequenced Packet Exchange (IPX/SPX) is a networking protocol suite used primarily in Novell NetWare environments. IPX is a network layer protocol responsible for addressing and routing packets, while SPX is a transport layer protocol that ensures reliable, sequenced packet delivery. Together, the IPX/SPX suite allows for efficient communication and data exchange between computers in a network.


The phonetics for the keyword “Internetwork Packet Exchange/Sequenced Packet Exchange” are:- Internetwork: /ˌɪntərˈnɛtwərk/- Packet: /ˈpækɪt/- Exchange: /ɪksˈʧeɪndʒ/- Sequenced: /ˈsiːkwənst/So together, it can be pronounced as: /ˌɪntərˈnɛtwərk ˈpækɪt ɪksˈʧeɪndʒ/ and /ˈsiːkwənst ˈpækɪt ɪksˈʧeɪndʒ/.

Key Takeaways

  1. Internetwork Packet Exchange (IPX) and Sequenced Packet Exchange (SPX) are networking protocols primarily used in Novell NetWare environments, providing connectionless and connection-oriented services respectively.
  2. IPX operates at the Network layer (Layer 3) of the OSI model, enabling communication across multiple networks, while SPX operates at the Transport layer (Layer 4), ensuring reliable and error-checked data delivery between devices.
  3. Although largely considered outdated and replaced by TCP/IP for most networking purposes, IPX/SPX may still be found in some legacy systems and specialized situations requiring minimal configuration and efficient routing.


Internetwork Packet Exchange/Sequenced Packet Exchange (IPX/SPX) is an important technology term as it refers to a networking protocol suite used primarily in Novell NetWare environments during the 1980s and 1990s.

IPX/SPX played a crucial role in facilitating the communication between computers and networks by providing connectionless (IPX) and connection-oriented (SPX) services, ensuring reliable and efficient data transmission.

As a robust, transparent, and routable protocol suite, it contributed significantly to the growth and acceptance of LAN environments, laying the groundwork for future networking developments.

Although IPX/SPX has largely been replaced by TCP/IP as a standard protocol, it remains significant for its historical impact and influence on the evolution of computer networking.


Internetwork Packet Exchange (IPX) and Sequenced Packet Exchange (SPX) are two communication protocols designed to enable data transmission and network connectivity between personal computers in a LAN or interconnected networks. Primarily used on Novell NetWare operating systems in the 1980s and 1990s, IPX/SPX aimed to provide reliable and efficient communication within and across diverse network environments.

The main purpose of these protocols was to offer an alternative to the traditional TCP/IP protocol suite, which was the de facto standard for internet-based communication. Their adoption led to the establishment of robust corporate networks that facilitated seamless data sharing and resource management among connected devices.

IPX, a connectionless transport protocol, operates on the network layer and is responsible for discovering optimal data-routing paths, addressing, and delivering data packets between computer nodes. On the other hand, SPX serves as a connection-oriented transport protocol, working on top of IPX to manage the data transfer process, ensuring that data packets arrive in the correct order and without errors.

As its name implies, SPX keeps a sequence of every packet in the transfer process, allowing it to identify and retransmit any lost or corrupted packet. Ultimately, the combination of IPX/SPX provided robust and efficient networking capabilities, promoting seamless collaboration and information exchange among users and devices in disparate networking systems.

Examples of Internetwork Packet Exchange/Sequenced Packet Exchange

Internetwork Packet Exchange (IPX) and Sequenced Packet Exchange (SPX) are networking protocols primarily used on Novell NetWare operating systems. They played significant roles in computer networking during the late 1980s to the late 1990s. Here are three real-world examples where IPX/SPX technology was implemented:

Corporate Networks: During the late 1980s and throughout the 1990s, Novell NetWare was the leading local area networking (LAN) software used by many corporate networks. IPX, as the network layer protocol, was responsible for addressing and forwarding packets to different network nodes, while SPX offered transport layer services ensuring reliable and orderly data transmission between computers. As a result, IPX/SPX played a crucial role in helping businesses manage their network operations efficiently.

Gaming: Popular video games during the 1990s, such as Warcraft II, Diablo, and Duke Nukem 3D, used IPX/SPX to enable multiplayer gaming over LANs. This allowed players to compete with each other in real-time across connected computers, making these games more engaging and challenging.

Network Devices and Internetworking: IPX/SPX was supported by various network devices, such as routers, switches, and hubs, enabling communication between computers using other protocols, like TCP/IP. Using IPX-to-IP or IPX-to-AppleTalk routers, for example, allowed companies to interconnect networks that used IPX/SPX, TCP/IP, and AppleTalk protocols.

FAQ – Internetwork Packet Exchange/Sequenced Packet Exchange

1. What are Internetwork Packet Exchange (IPX) and Sequenced Packet Exchange (SPX)?

Internetwork Packet Exchange (IPX) and Sequenced Packet Exchange (SPX) are networking protocols used mainly in Novell NetWare environments. IPX is responsible for network services, including data transmission, while SPX is responsible for connection management, ensuring that data packets are received in the correct order.

2. What is the role of IPX in networking?

IPX is a datagram protocol that provides network addressing and routing capabilities for transmitting packets between network nodes. It is connectionless and does not require setup or teardown of connections, enabling it to have lower overhead and reduced complexity compared to connection-oriented protocols.

3. How does SPX enhance IPX communication?

Sequenced Packet Exchange (SPX) adds a connection-oriented functionality to the inherently connectionless IPX. It ensures reliable, in-order delivery of data packets, error detection, and correction. By using sequences and acknowledgements, SPX provides a reliable communication layer for applications requiring guaranteed packet delivery.

4. Are IPX and SPX still in use today?

IPX and SPX, once highly popular in Novell NetWare environments, have significantly declined in usage with the advent of the TCP/IP protocol suite. However, some legacy systems may still utilize IPX and SPX, requiring network administrators to have knowledge of these protocols for troubleshooting and maintenance purposes.

5. Can IPX and SPX operate over the Internet?

IPX and SPX were not designed for Internet communication, as they do not work well with the TCP/IP networking stack that the Internet relies upon. However, tunneling methodologies such as IPX Over IP may be used in specific cases to encapsulate IPX traffic within IP packets for transport across the Internet.

Related Technology Terms

  • IPX/SPX Protocol Stack
  • Routing Information Protocol (RIP)
  • Service Advertising Protocol (SAP)
  • Novell NetWare
  • Transmission Control Protocol/Internet Protocol (TCP/IP)

Sources for More Information


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