HP X.25 for OpenVMS Alpha and I64 Systems, V2.0

HP X.25 for OpenVMS Alpha and I64 Systems, V2.0 SPD 47.37.16
The device drivers all support full-duplex HDLC framing.
In all cases, the data throughput over the synchronous
lines is dependent on the user applications and system
environment.
The device drivers support modem control signals (DTR,
DCD, DSR, RTS and CTS) where these signals are pro-
vided by the selected electrical interface.
Supported controllers for Alpha are listed in Table 4.
WAN device drivers include a pseudodriver (WAN-
DRIVER) that provides a programming interface to the
Data Link level for the LAPB, DEC-HDLC, and LLC2
protocols. The pseudodriver also provides an interface
to the physical layer of the synchronous communica-
tions devices supported by the product. The physical
layer interface provides the ability to read and write
HDLC formatted frames (leading/trailing flag, HDLC
frame check sequencing, HDLC bit stuffing), but pro-
tocol interpretation of the frames must be provided by
the user application using the interface.
Optional Facility Support
Table 1 describes the Optional User Facilities of the
1988 ITU/TSS X.25 recommendations that HP X.25 for
OpenVMS supports.
Support for any facility is dependent on the PSDN used.
The product documentation describes specific facility
availability for supported PSDNs.
Table 1
Optional User Facilities Support
ITU/TSS
X.25
(1988)
refer-
ence Optional User Facility
Sup–
port
1
6.1 On–line facility registration no
6.2 Extended packet sequence numbering yes
6.3 D bit modification n/a
6.4 Packet retransmission no
6.5 Incoming calls barred n/a
6.6 Outgoing calls barred n/a
6.7 One–way logical channel outgoing yes
6.8 One–way logical channel incoming yes
6.9 Non–standard default packet sizes yes
6.10 Non–standard default window sizes yes
6.11 Default throughput class assignment yes
6.12 Flow control parameter negotiation yes
6.13 Throughput class negotiation yes
6.14.1 Closed User Group (CUG) yes
6.14.2 CUG with outgoing access yes
6.14.3 CUG with incoming access yes
6.14.4 Incoming calls barred within a CUG n/a
6.14.5 Outgoing calls barred within a CUG n/a
6.14.6 CUG selection yes
6.14.7 CUG with outgoing access selection yes
6.15.1 Bilateral Closed User Group (BCUG) yes
6.15.2 BCUG with outgoing access n/a
6.15.3 BCUG selection yes
6.16 Fast select yes
6.17 Fast select acceptance n/a
6.18 Reverse charging yes
6.19 Reverse charging acceptance n/a
6.20 Local charging prevention n/a
6.21.3 NUI selection yes
6.22 Charging information yes
6.23.2 RPOA selection yes
6.24 Hunt group no
2
6.25.1 Call redirection n/a
6.25.2.2 Call deflection selection no
6.25.3 Call redirection or call deflection
notification
yes
6.26 Called line address modified notifica-
tion
no
6.27 Transit delay selection and indication yes
6.28 TOA/NPI address selection and
indication
no
7.1 Non–X.25 facilities yes
G.3.1 Calling Address Extension yes
G.3.2 Called Address Extension yes
G.3.3.1 Minimum throughput class yes
G.3.3.2 End–to–end transit delay yes
G.3.3.3 Priority yes
G.3.3.4 Protection yes
G.3.4 Expedited data negotiation yes
1
Refers to those features of a facility that are relevant to the operation of a
DTE. ‘‘n/a’’ refers to DCE facilities requiring no action from the DTE.
2
The individual DTEs must be assigned addresses independent of the hunt
group address.
4