Common networking standards, ATM on AS/400

Chapter 10. Common networking standards

These topics introduce the types of common networking standards that are supported by the AS/400 system. See the following topics for more information:

vLocal area network standards

vWide area network standards

Local area network standards

A LAN (local area network) is a communications system that allows interconnection and the sharing of resources between independent devices within a moderately sized geographic area. These topics introduce the types of local area networks that are supported by the AS/400 system:

vAsynchronous transfer mode (ATM)

vDDI (distributed data interface) networks

vEthernet

vToken-ring

vWireless networks

ATM on AS/400

Asynchronous Transfer Mode (ATM) provides a very fast and flexible network protocol. When used with LAN emulation, you can run token-ring and Ethernet on ATM to take advantage of ATM’s superior speed, throughput, and flexibility.

ATM LAN emulation connects LAN clients at multi-megabit-per-second speeds over distances previously possible only with a wide area network (WAN). LAN emulation makes client connections as they are needed, without configuring the physical path between the end systems. Switching is the mechanism by which the network completes connections from one device to another.

The AS/400 asynchronous transfer mode (ATM) network interface (NWI) describes everything that is common across the ATM physical interface. Each AS/400 ATM input/output adapter (2809 or 2810) may have one network interface attached. A single line description attaches to the NWI. The line description can define either an Ethernet or token-ring local area network (LAN) emulation client by using switched virtual circuit connections, permanent virtual circuit connections, or direct connections.

For more information on ATM, see the topic ATM on AS/400.

Distributed data interface network

FDDI is an optical fiber-based local area network (LAN) that uses the American National Standards Institute (ANSI) 3T9.5 standard for a token-passing ring media access control (MAC) protocol. Stations, concentrators, and bridges in a FDDI network are physically connected to one of the counter-rotating rings or both of the counter-rotating rings. The rings operate at 100 Mbps.

FDDI networks allow devices to be attached to one or both of the rings. Usually only the primary ring in a FDDI network is active. The secondary ring is used to maintain the network when a dual-access station or a concentrator becomes inactive.

Ethernet networks

Ethernet is one type of local area network (LAN) topology that is supported by the Operating System/400 licensed program. OS/400 Ethernet provides support for the Digital Equipment Corporation, Intel Corporation, and Xerox standard (Ethernet Version 2) and the IEEE 802.3 standard.