background image

CHAPTER 2: Introduction

11

The Fradswitch employs a unique funneling method for controlling network congestion and moderating
feeder throughput speed.

CCLM and LMI management protocols are supported, and operation is in compliance with ANSI T1.606,
T1.619, T1.617 Annex D, and ITU Q.922, Annex A.

2.5 HDLC Link Features

The Fradswitch links can be programmed to operate with transparent HDLC allowing computers, bridges,
and HDLC communication devices to be connected over X.25 or Frame Relay networks. The HDLC
protocol is encapsulated over the X.25 or Frame Relay protocol, providing end-to-end transparent
operation. (See 

Figure 2-6

.)

2.6 ASYNC Link Features

The Fradswitch links can be programmed to operate asynchronously, allowing connection of asynchronous
devices to the links. When programmed to operate as async, the links operate like Fradswitch series async
channels with all the standard facilities. (See 

Figure 2-3

.)

2.7 Buffer Capacity

The Fradswitch series uses dynamic on-demand allocation of data buffers, in accordance with the channels
and links traffic conditions. The Fradswitch series automatically changes the buffer allocation on-line, 
to make the best possible use of the free RAM capacity.

The standard Fradswitch RAM size is 256 KB; as an option, the Fradswitch can be ordered with 
1024 KB RAM, to increase the throughput in environments that generate high traffic volumes.

2.8 Asynchronous Channel Interface Characteristics

Channel operation is asynchronous. The asynchronous word format is user-configurable, by means of
proprietary extension to the ITU X.28 basic set of commands. For flexibility in applications, flow control 
can be performed either by software (X-ON/X-OFF) or by hardware handshaking.

All of the Fradswitch channels have RS-232/V.24 DCE interfaces. Each channel has its own eight-pin 
RJ-45 connector.

2.9 Channel PAD Characteristics

The Fradswitch includes eight essentially independent PADs, one for each channel. All the channel 
PADs share the three X.25 physical links. The channel PADs support multiple sessions with independent,
user-selected session profiles. This means that any user connected to one of the Fradswitch channels can
simultaneously conduct several virtual circuits carried by different logical channels. The maximum number
of sessions per channel is up to 4.

Summary of Contents for Fradswitch-16A

Page 1: ...blackbox com E mail info blackbox com CUSTOMER SUPPORT INFORMATION MARCH 1995 MT720A 232T MT721AE X21T MT720A 35T MT722A 232T MT720AE X21T MT722A 35T MT721A 232T MT722AE X21T MT721A 35T Fradswitch 8A...

Page 2: ...is operated in a commercial environment Operation of this equipment in a residential area is likely to cause interference in which case the user at his own expense will be required to take whatever m...

Page 3: ...an el flujo de aire por los orificios de ventilaci n 10 El equipo el ctrico deber ser situado fuera del alcance de fuentes de calor como radiadores registros de calor estufas u otros aparatos incluyen...

Page 4: ...18 3 1 Unpacking 18 3 2 Site Requirements 18 3 3 Fradswitch Hardware Configuration Information 19 3 3 1 General Information 19 3 3 2 Internal Jumpers 20 3 3 3 Interface Board 22 3 3 4 Jumper Setting P...

Page 5: ...t window w Timers T1 T3 T10 T11 T12 T13 and number of retries N2 Allocation of logical channels Link Level Procedure LAPB can act as DTE or DCE at layers 2 and 3 Modulo 8 128 power sequencing Frame wi...

Page 6: ...e 32 to 122 F 0 to 50 C Humidity Up to 90 noncondensing Power Supply Voltage 115 or 230 VAC depending which model you ordered 50 60 Hz Consumption 15W Fuse 125 mA 250V Size MT720A units 1 7 H x 17 W x...

Page 7: ...chronous port the packets are disassembled into asynchronous data and then routed to the destination port The Fradswitch links can be programmed to operate asynchronously allowing connection of asynch...

Page 8: ...ching See Figure 2 5 Connection of devices supporting HDLC protocol to the X 25 or Frame Relay network See Figure 2 6 Figure 2 1 Fradswitch 8A serving as backbone for private X 25 data networks STAT M...

Page 9: ...Figure 2 3 Fradswitch 8A serving as a PAD with redundant link and load sharing One link configured as async channel FRADSWITCH 8A STM X 25 X 25 64 Kbps COMPUTER STAT 24 MX868A X 25 PUBLIC NETWORK X 25...

Page 10: ...ing as a FRAD at the user side Conversion of Frame Relay to async Figure 2 5 Fradswitch 8A serving as a backbone for Frame Relay private data network X 25 FRAME RELAY FRAME RELAY FRAME RELAY FRAME REL...

Page 11: ...s LAPB per ITU X 25 and the Fradswitch can act as either DTE or DCE with respect to the layer 2 and layer 3 protocols 2 4 Frame Relay Link Features When a link is configured for Frame Relay packets ar...

Page 12: ...traffic conditions The Fradswitch series automatically changes the buffer allocation on line to make the best possible use of the free RAM capacity The standard Fradswitch RAM size is 256 KB as an opt...

Page 13: ...ed call Automatic call setup retry the user can specify the number of retries and the interval between consecutive retries An alternative address for call setup that is automatically used when it is n...

Page 14: ...gured for different profiles including profiles dedicated to specific sessions The command facility can also be used to prepare a local library of call setup sequences network user identification data...

Page 15: ...ss Selection of layer 2 and layer 3 modules DCE or DTE Selection of the various LAPB timers and parameters Selection of default window and packet sizes Definition of logical channel allocation permane...

Page 16: ...ssible to program the Fradswitch series to transmit the same reports to both destinations and thus to make sure that the reports will reach a management station or to send different types of informati...

Page 17: ...ogical channel The number of active logical channels and active sessions The number of buffers currently allocated to the transmit to network and receive to user directions Autocall ID mnemonic config...

Page 18: ...et and restart packets transmitted and received by layer 3 Number of logical group in use Current packet size 2 18 Diagnostic Features Upon power up or after reset the Fradswitch performs a self test...

Page 19: ...ge 3 2 Site Requirements Power The Fradswitch should be installed within 5 feet 1 5 m of an easily accessible grounded AC outlet capable of furnishing 115 or 230 VAC in accordance with the nominal sup...

Page 20: ...order and is not field replaceable See Section 3 3 3 for more information it provides information on the functions of the internal jumpers and provides step by step instructions for setting these jum...

Page 21: ...Figure 3 2 and use the following information CH GND jumper JP1 This jumper controls the connection between the signal ground lines to the chassis ground lines The appropriate position must be determin...

Page 22: ...by the user during the last configuration session INIT Initialization When it is turned on the Fradswitch loads the default configuration determined by the factory and common to all the Fradswitch se...

Page 23: ...es its clock from outside and the clock parameter must be configured as external clock see Section 2 3 in the Packet Switching Guide When the board is a DTE interface board the link uses the Fradswitc...

Page 24: ...ase as shown in Figure 3 3 To prepare the unit for rack installation attach the two brackets to the side walls of the unit Each bracket is fastened by means of two screws with flat washers which are i...

Page 25: ...allocation in Fradswitch series data channel connectors and provides typical wiring diagrams for straight through and cross over cables 3 5 2 X 25 LINK CONNECTION Fradswitch X 25 link interfaces are...

Page 26: ...ded with a protective earth contact The protective action must not be negated by use of an extension cord without a protective conductor grounding Make sure that only fuses with the required rated cur...

Page 27: ...controls indicators and connectors Item Control Indicator or Connector Function 1 PWR Indicator Lights when the Fradswitch is powered 2 Main Link Activity Indicators Indicators one for each main link...

Page 28: ...or after pressing the RESET pushbutton 6 OVF Indicator Lights when the Fradswitch s buffers are full In a properly designed system this condition usually indicates that one of the DTE units connected...

Page 29: ...ion numbers in Figure 4 2 Figure 4 2 Fradswitch 8A rear panel controls and connectors Table 4 2 Fradswitch 8A rear panel controls and connectors Item Control or Connector Function 1 Power Connector AC...

Page 30: ...ration the PWR SYNCs and MAINs indicators should light continuously and the TEST OVF and ERR indicators must remain off Channel activity indicators flash according to the traffic load and go out when...

Page 31: ...dministrator may not allow you to perform certain activities Passwords may have been used to restrict the access to certain functions 5 1 Connecting to the Fradswitch Command Facility If the Fradswitc...

Page 32: ...tory default password is a carriage return The Fradswitch sends the main menu of the command facility Figure 5 2 Figure 5 2 Main menu MAIN MENU 1 CONFIGURE 2 SYSTEM CONTROL 3 DIAGNOSTICS 4 STATUS and...

Page 33: ...nearest X 25 peer data Enter the Fradswitch command facility see Section 5 1 On the Fradswitch main menu select 1 CONFIGURE and then select 3 Link On the Fradswitch link configuration menu select 3 Up...

Page 34: ...routing table entry configuration menu select 1 Add routing table entry and then enter 1 On the Fradswitch routing table entry 1 configuration menu select 1 Destination link and then enter L Local ch...

Page 35: ...ion menu 5 3 2 STM PTOTOCOL CONFIGURATION 1 In the MAIN MENU press option number 1 CONFIGURE 2 Press 3 Link then press 1 Set Link Type 3 Select any link number between 1 and 3 4 Select Link type 6 for...

Page 36: ...not change the parameters already defined in the Stat 4 5 4 Weight Oriented Routing Function Whenever a call command is issued the interface from which the call is to be connected is selected using a...

Page 37: ...uted to link 1 only the set of addresses 123456700 123456788 can be routed to links 2 7 and every address 12000000 123456699 should be routed to links 8 12 in an increasing priority The screens below...

Page 38: ...6 4 Address 12XXXXXXX 5 Stop search 1 S Save CR Exit 1 Link 8 6 Link prio 1 2 Link 9 7 Link prio 2 3 Link 10 8 Link prio 3 4 Address 12XXXXXXX 5 Stop search 0 S Save CR Exit 1 Link 5 6 Link prio 1 2 L...

Page 39: ...eter nn If you want to see the new parameter values type a after SET 5 6 Calling Procedures In order to make a manual call to any destination the Fradswitch channel must be in command mode If the chan...

Page 40: ...d type C the mnemonic and then press the CR key Multiple Sessions To change the current session or to start a new session use the following procedure If an active call is handled by the current sessio...

Page 41: ...NOTES...

Page 42: ...1000 Park Drive Lawrence PA 15055 1018 724 746 5500 Fax 724 746 0746 Copyright 1995 Black Box Corporation All rights reserved...

Reviews: