Expand Configuration and Management Manual (H06.21+, J06.10+)

Expand Overview
Expand Configuration and Management Manual — 529522-013
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Multiple Communications Environments
Multiple Communications Environments
Nodes in an Expand network can be connected using a variety of data communications
technologies and protocols. A single network can consist of any combination of these
different data communications methods.
Nodes in an Expand network can be connected by
•
Full-duplex leased lines or satellite connections using the High-Level Data Link
Control (HDLC) protocol
•
X.25 virtual-circuit connections to a packet-switched data network (PSDN)
•
Connections to IBM Systems Network Architecture (SNA) networks
•
Local area network (LAN) or wide area network (WAN) connections to networks
that use the Internet Protocol (IP)
•
Local area network (LAN) or wide area network (WAN) connections to
Asynchronous Transfer Mode (ATM) networks
•
Single-mode fiber-optic cables (ServerNet clusters)
Leased and Satellite Connections
You can connect Expand nodes with leased or satellite lines using either the HDLC
Normal protocol or the HDLC Extended Mode protocol.
•
The HDLC Normal protocol is provided for use with conventional voice-grade
leased-line and switched-line facilities.
•
The HDLC Extended Mode protocol is a satellite-efficient version of HDLC and is
provided for use with satellite connections.
X.25 Packet-Switched Networks
X.25 is a standard for private and public networks that use packet-switching
technology. Some examples of packet-switched networks include SPRINTNET,
TELENET, and TYMNET in the United States; DATAPAC in Canada; DATEX in
Germany; TRANSPAC in France; and PSS in Great Britain.
Expand-over-X.25 connections are provided with the HP X.25 Access Method
(X25AM) product. The Expand subsystem uses the NETNAM protocol to communicate
with an X25AM line-handler process.
Note. There is no automatic dialing function within the Expand subsystem for dial-up lines.