Features

The X.25/ACC Subsystem supports the following features:

Compliance with industry and international standards:

Complies with the 1980, 1984, and 1988 CCITT (ITU-T) recommendation for X.25.
Complies with the U. S. Defense Data Network (DDN) TCP/IP—X.25 standard protocols.
Supports ARPA/Berkeley Services (except ruptime and rwho) for HP 9000 computers over the X.25/ACC.
Supports level 2 and LAP-B/LAP-D access.
Supports layer 3 interoperability for HP 9000-to-HP 9000 and HP 9000-to-HP 3000 communications.
Provides ability to write customized programs to layer 4 over TCP/IP via BSD IPC. (ARPA Services/9000 are required for application development using Berkeley Services.)
Implements industry standard Defense Advanced Research Agency (DARPA) TCP/IP protocols.

Transparent access over multiple network nodes:

Dynamic packet routing and gateway capabilities through the use of ARPA/Berkeley Services over Internet Protocol (IP).
Provides interface with UUCP.
Provides OSI Transport Services interface with OTS/9000.
Remote display terminals are supported by implementation of host PAD capability (1984 CCITT recommendations X.3 and X.29).
Host PAD emulation and remote PAD printer are also supported by this product.
All HP-UX applications, with the exception of block-mode applications and mail exchange are supported on remote terminal connections.

X.25/ACC plus HP X.25/9000 Streams Product

The primary difference between X.25/ACC Streams and the HP X.25/9000 Streams product is the addition of software to enable X.25 Streams to run over ACC network interface cards. The X.25/ACC product uses the same software as the HP X.25/9000 product to provide standard X.25 interfaces and services. This means that the use of the X.25/ACC Subsystem is substantially the same as the HP X.25/9000 product. There are some differences, however, due to the differences in the hardware. These differences are summarized below:

Use of the x25mibstat utility is not supported by the X.25/ACC product.
Network tracing using the nettl tracing and logging facility that is provided by the X.25/9000 product is partially supported for the X.25/ACC Subsystem. Network logging using nettl is used for all errors and warnings logged by the X.25/ACC NLI2ZCOM driver (N2Z). The X.25/ACC product does not support level 2 tracing or use of the strace utility. Level 3 tracing using nettl is supported. However, because the ACC cards execute the X.25 protocol on the card rather than in the host, some details are not available. Specifically RR packets and the P(R)/P(S) values.
The use of SAM is not supported. For the X.25/9000 product, SAM can be used to create x25init configuration files, and to bring up and down X.25 Level 2 connections. For X.25/ACC, utilities are provided to create default x25init configuration files, and to bring up and down the X.25/ACC Subsystem. (Refer to Chapter 2 “Software Installation and Verification” for more information on these utilities.)
There may be some minor differences in the information displayed by the X.25 status utilities. This is due to differences in the implementation of the firmware and drivers.
End-to-end Application D-bit acknowledgments are supported, but by default are turned off in the X.25/ACC software. This feature can be turned on by modifying the value of the n2z_end_to_end_acks kernel tunable parameter. Refer to the appendix on turning and sizing for detailed information.

4-Channel X.25/ACC Compared Against Other ACC Interfaces

There is also a notable difference in the configuration requirements for the 4-Channel T1/E1 interface, relative to the 8-channel or 2-Channel ACC interface cards. In general, implementation of sub-channel and timeslot features for the 4-Channel interface results in differences for device files, parameters related to Interface Definition, Port Definition, and tunable parameters. Specific differences are detailed in the sections in which these topics are described.

Features

Technical documentation

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X.25/ACC plus HP X.25/9000 Streams Product

4-Channel X.25/ACC Compared Against Other ACC Interfaces