X.25 DATA NETWORKING

Series 8000

8295 Mini-Switching
Multi-Protocol PAD/FRAD

Typical 8295 installation

Cost-effective networking

The 8295 PAD/FRAD offers extensive support for IBM SNA/SDLC and other synchronous protocols, including frame relay and X.25. The 8295 PAD/FRAD is both a powerful X.25 PAD/concentrator, as well as a frame relay access device. Seven of the user ports can be configured for any protocol , while a further eighth port is dedicated to async only. The PAD/FRAD can be connected to computer equipment without having to provide additional host ports or change applications software. To the host and terminal equipment the network can appear unchanged.

Protocol support	User port	Trunk
3270 SNA	Yes	—
3270 BSC	Yes	—
SDLC	Yes	—
NSDLC	Yes	—
QLLC	Yes	—
TBOP	Yes	—
TSYNC	Yes	—
ASYNC	Yes	—
VIP	Yes	—
X.25	Yes	Yes
FRAME RELAY	—	Yes

PAD/FRAD basic unit

The PAD/FRAD can be housed in a wide variety of enclosures from cost effective two slot enclosures (offering dual PSU operation) up to large backbone PSEs. The card version is housed in the 8100S, 8210 and 8310 basic units, and also in the 8325 PSE ; the module is housed in the 8525 backbone PSE. Both the card and module versions of the PAD/FRAD offer identical functionality and performance. This variety of options provides extremely cost effective solutions for every requirement. For higher performance, the SuperPAD/FRAD may be more suitable.

X.25 to frame relay migration

The 8295 PAD/FRAD can act both as a PAD (X.25 packet assembler/disassembler) and a FRAD (frame relay access device), because each of its network ports can be configured to support either of these networking protocols. This important FRAD capability provides an easy migration for users who choose to move from X.25 to frame relay; it also allows a public X.25 network, for example, to be used as a back-up to frame relay.

Multi-protocol and multi-vendor

On its user ports, the 8295 PAD/FRAD supports X.25, Async, QLLC, 3270 SNA/SDLC, 3270 BSC, VIP, 7700/7800 and generic SDLC. The 8295 PAD/FRAD's transparent option offers TSYN, for support of all 'SYN' based protocols and TBOP (bit-oriented protocol) for transporting all flag based protocols (eg. HDLC/router traffic, over X.25 or frame relay). All protocols are configurable on a per port basis.

Intelligent emulation

The 8295 PAD/FRAD implements emulations for IBM 3270SNA, IBM 3270BSC and Bull VIP 7700/7800, which means that all 'polling' by the host is restricted to the edges of the network, only data traverses the network, which speeds response and reduces line costs. As well as removing the burden of X.25 support from the host, an 8295 PAD/FRAD solution means that the real topology of the network does not need to match that 'seen' by the host.

User switching and dual session

For 3270 BSC and SNA the 8295 PAD/FRAD performs sophisticated full emulation which allows IBM users to dynamically switch between hosts – independent of the cluster controller. Users can also maintain two simultaneous host sessions and 'hot-key' between them.

Automatic backup and restore

The PAD/FRAD features an innovative backup capability, that offers automatic backup over ISDN or modem circuits in the event of main link failure, this includes auto-restoral when the main link is returned to service, saving on back-up costs.

No loss of data

The 8295 PAD/FRAD operates its own transport and session control mechanism to provide the essential guarantee of no data loss in the event of trunk failure, automatic re-routing to another trunk will bypass the failure.

Management

Management is provided via local and remote asynchronous terminals as well as from a centralised DomainView Network Management System. An extra (eighth) port is dedicated to asynchronous operation, so that local access to the management function is always available if required.

TECHNICAL SPECIFICATIONS

X.25 Interface

• CCITT 1980 and 1984, X.121
• Logical channel types: SVC or PVC
• Packet size: 128, 256, 512 bytes
• Level 2 framing: Modulo 8 or 128
• Max LCNs: 512
• Calling address insertion & substitution
• Called address translation
• X.25 general facility support
• Flow control parameter negotiation
• Throughput class negotiation (transparent)
• Incoming/outgoing calls barred
• One-way logical channel outgoing/incoming
• Closed user group (passed transparently)
• Fast select acceptance
• Facilities on a per call basis:
• Closed user group (passed transparently)
• Flow control parameter negotiation
• Fast select, transit delay selection and indication
• Throughput class negotiation (transparent)
• Frame relay interface

Standards

• RFC1490, ANSI TI.606
• (CCITT Q.922/Annex A), TI.617/Annex D

Link Protocol

• LAP-F
• Frame Size: 133 to 512 bytes
• Max DLCIs: 256

Networking features

• Local X.25 or frame relay switching
• DLCI broadcast facility
• Committed information rate
• Call balancing across dual links
• Alternate routing on local link failure
• Automatic transport re-connect
• Automatic backup and restore
• Accelerated data forwarding
• EIA signal level display

Unit management

• Menu and form driven (VT100)
• Password protected, Inactivity time-out
• Local access: by async terminal
• Remote access: by async terminal (via PAD and X.25)
• Inherent real time diagnostics
• 'Datascope'-style data display
• EIA Signal level display
• Management by DomainView
• Configuration load and dump
• Event reporting
• Unit restart
• Remote log-on to unit manager

Device support specifications

Asynchronous summary

• Terminal-based switching connections
• Max 8 terminals (1 per port)
• CCITT (1984) X.3, X.28, X.29

3270 SNA/SDLC summary

• Terminal-based (LU) switching cnxs, max 80 LUs.
• Max CLCs (cluster controllers): 20
• SNA PU connections: PU4 to PU2
• SNA LU types: LU 1,2 or 3
• SDLC frame size: 4 Kbytes
• XIDs: formats 0 or 1
• Data code: EBCDIC, Line encoding: NRZ or NRZI

Typical environments

• Control units: 3174, 3274.
• Comms. controllers: 3725, 3745, 3720, 3705.
• Hosts: System/370: 30xx, 93xx .
• Applications: VM, MVS, VTAM, CICS/VS

Generic SDLC summary

• CLC- based pre- configured cnxs, max 40 CLCs
• SNA PU types: 1, 2, 2.1 or 4
• SDLC frame size: 8 Kbytes
• XIDs: emulated: formats 0 or 1
• Transparent: formats 0, 1, 2 or 3
• NSDLC option: SDLC station role-negotiation, for PU4-PU4 or PU2.1-PU2.1 connections
• QLLC option: applies in terminal-site units only, PU4-PU2 connections for SDLC-only CLCs
• Data code: EBCDIC
• Line encoding: NRZ or NRZI

Typical environments

(as 3270 SNA, plus:)
• Control units: 5294, 5394, PC. Hosts: AS400,
• System 36, 38. Application: LU6.2 type (e.g. APPC)

Transparent BOP summary

• Port-based pre-configured cnxs, max 7
• Any sync protocol having FLAG-delimited blocks (eg. HDLC, DCX ARQ and UDLC)

3270 BSC summary

• Terminal-based switching cnxs, max 80 terminals
• Data code: EBCDIC or ASCII

Typical environments

(as 3270 SNA above, plus:)
• Bank ATMs (eg. Phillips)

Transparent SYN summary

• Port-based pre-configured connections, max 7
• Any character-oriented sync protocol having 'SYN' -delimited blocks

Typical Environments

• 2780/3780, HASP, ICL, Siemens MSV, NCR etc.

VIP 7700/7800 summary

• Terminal-based switching cnxs, max 80 terminals VIP synchronous only

Typical environments

• Terminals: HDS 5,6,7 etc.
• Network processors: Datanet, microFEP
• Hosts: DPS range

Ports for all hardware variants

Ordering information

8100S chassis options

8295/BU 230v Single PSU
8295/BU/24 24v Single PSU
8295/BU/48 48v Single PSU
8295/BU/115 115v Single PSU
8295/BU2 230v Dual PSU
8295/BU2/24 24v Dual PSU
8295/BU2/48 48v Dual PSU
8295/BU2/115 115v Dual PSU

8295/Card – for 8210, 8310 and 8325
8295/Module – for 8425 and 8525

View data sheet for 8295 Mini-Switching Multi-Protocol PAD/FRAD

For more information on the 8000 series, please contact Marketing