Cisco PA-2JT2 Operating and maintenance instructions

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PA-2JT2 6.3-MHz Serial Port Adapter Installation
and Configuration
Product Numbers: PA-2JT2 and PA-2JT2=
This configuration note describes how to install and configure the Japan T2 Line (JT2) 6.3-megahertz
(MHz), 2-port, serial port adapter (PA-2JT2[=]), which is used on the second-generation Versatile
Interface Processor (VIP2) in all Cisco 7500 series and in Cisco 7000 series routers using the 7000
Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI). (For
complete and specific compatibility requirements, refer to the section “Software and Hardware
Prerequisites” on page 3.)
Use this configuration note in conjunction with the configuration note Second-Generation Versatile Interface Processor (VIP2)
Installation and ConfigurationDocument Contents
This configuration note is organized into the following sections:
•Related Documentation, page 2
•JT2 Port Adapter Installation Prerequisites, page 3
•What Is the JT2 Port Adapter?, page 7
•VIP2 and the JT2 Port Adapter, page 12
•Obtaining Documentation, page 24
•Obtaining Technical Assistance, page 25

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Related Documentation
Related Documentation
The documentation listed below is available online, on the Documentation CD-ROM, or as printed
documents.
Your router, switch, or gateway and the Cisco IOS software running on it contain extensive features and
functionality, which are documented in the following resources:
•Cisco IOS software:
– For configuration information and support, refer to the modular configuration and modular
command reference publications in the Cisco IOS software configuration documentation set
that corresponds to the software release installed on your Cisco hardware.
– To check the minimum software requirements of Cisco IOS software with the hardware installed
on your router, Cisco maintains the Software Advisor tool on Cisco.com:
http://www.cisco.com/cgi-bin/Support/CompNav/Index.pl. You must be a registered user on
Cisco.com to access this tool.
Note You can access Cisco IOS software configuration and hardware installation
and maintenance documentation on the World Wide Web at
http://www.cisco.com/public/countries_languages.shtml.
•Cisco 7000 series routers:
For hardware installation and maintenance information, refer to the following publications:
– Cisco 7000 Hardware Installation and Maintenance that shipped with your router.
– Second-Generation Versatile Interface Processor (VIP2) Installation and Configuration
– Fourth-Generation Versatile Interface Processor (VIP4) Installation and Configuration
– Versatile Interface Processor (VIP6-80) Installation and Configuration
•Cisco 7500 series routers:
For hardware installation and maintenance information, refer to the following publications:
– Cisco 7500 Installation and Configuration or the quick start guide that shipped with your router
– Second-Generation Versatile Interface Processor (VIP2) Installation and Configuration
– Fourth-Generation Versatile Interface Processor (VIP4) Installation and Configuration
– Versatile Interface Processor (VIP6-80) Installation and Configuration
•For international agency compliance, safety, and statutory information for WAN interfaces:
– Regulatory Compliance and Safety Information for the Cisco 7000 Series Routers
– Regulatory Compliance and Safety Information for the Cisco 7500 Series Routers
– Site Preparation and Safety Guide
•To view Cisco documentation or obtain general information about the documentation, refer to the
following sections:
– Obtaining Documentation, page 24
– Obtaining Technical Assistance, page 25
– Customer service at 800 553-6387 or 408 526-7208. Customer service hours are 5:00 a.m. to
6:00 p.m. Pacific time, Monday through Friday (excluding Cisco-observed holidays). You can
also send e-mail to [email protected].

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JT2 Port Adapter Installation Prerequisites
JT2 Port Adapter Installation Prerequisites
This section provides specific information you need to ensure a successful installation, and the following
information is included:
•Software and Hardware Prerequisites
•List of Parts and Tools, page 3
•FCC Class B Compliance, page 4
•Safety Guidelines, page 4
•Port Adapter Locations on the VIP2, page 8
Software and Hardware Prerequisites
For JT2 port adapters installed on the VIP2-40 in Cisco 7000 series or Cisco 7500 series routers,
Cisco IOS Release 11.1(12)CA1, or later, is required.
For JT2 port adapters installed on the VIP2-50 in Cisco 7000 series or Cisco 7500 series routers,
Cisco IOS Release 11.1(14)CA, or later, is required.
Note At a minimum, you must use the VIP2-40 (with 2 MB of SRAM and 32 MB of DRAM) or VIP2-50 (with
4 to 8 MB of SRAM and 32 to 128 MB of SDRAM) for use with one or two JT2 port adapters. We do
not recommend the use of any other VIP2 model with PA-2JT2.
Caution To prevent system problems, do not operate the VIP2 in Cisco 7000 series systems without the RSP7000
and RSP7000CI. The VIP2 will not operate properly with the Route Processor (RP), Switch Processor
(SP), or Silicon Switch Processor (SSP) installed in the earlier host Cisco 7000 series routers.
List of Parts and Tools
You need the following tools and parts to install a JT2 port adapter. If you need additional equipment,
contact a service representative for ordering information.
•PA-2JT2(=) and a VIP2-40(=) motherboard, with at least one available port adapter slot, and, a Cisco
7500 series router with at least one available interface processor slot, or a Cisco 7000 series router
(with an RSP7000 and RSP7000CI installed) with at least one available interface processor slot.
For specific VIP2 model requirements, refer to the note in the section “Software and Hardware
Prerequisites” on page 3.
•The appropriate Cisco IOS release loaded on your router. (For Cisco IOS software prerequisites,
refer to the section “Software and Hardware Prerequisites” on page 3.)
•One pair of unbalanced, 75-ohm (± 5% at 1 MHz), coaxial cables (with BNC connections) for each
interface port, appropriate for the port adapter interfaces on your JT2 port adapter. (75-ohm coaxial
cables are not supplied by Cisco systems; these cables are available from commercial cable
vendors.)

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JT2 Port Adapter Installation Prerequisites
The 75-ohm coaxial BNC connections must conform to JIS C5412-1976 high-frequency coaxial
C02-type connectors, which are equivalent to MIL C 3608 BNC connectors and coaxial cables. (For
specific cable requirements, refer to the section “JT2 Port Adapter Interface Connectors and Cables”
on page 10.)
Further, the 75-ohm coaxial cables must have ferrite sleeves around them to reduce the effects of
electromagnetic interference (EMI). Four ferrite sleeves are included with your JT2 port adapter
have the following specifications: 275 ohms @ 100 MHz.
•A B-type or C-type data service unit (DSU) with a 75-ohm, coaxial BNC input and an optical fiber
output, to which you attach the 75-ohm coaxial cables from the receive (RX) and transmit (TX) ports
on the JT2 port adapter. (Older A-type DSUs are not supported with PA-2JT2.)
Yo u r D S U must be capable of, and set to accept, external grounding because the JT2 port adapter’s
TX and RX connections are grounded at the router-chassis side.
•Number 1 Phillips and a 3/16-inch, flat-blade screwdriver.
•Your own ESD-prevention equipment or the disposable grounding wrist strap included with all
upgrade kits, FRUs, and spares.
FCC Class B Compliance
The equipment described in this publication generates and might radiate radio-frequency energy. If it is
not installed in accordance with Cisco’s installation instructions, it might cause interference with radio
and television reception. This equipment has been tested and found to comply with the limits for a Class
B digital device in accordance with the specifications in part 15 of the FCC rules. These specifications
are designed to provide reasonable protection against such interference in a residential installation.
However, there is no guarantee that interference will not occur in a particular installation.
You can determine whether your equipment is causing interference by turning it off. If the interference
stops, it was probably caused by the Cisco equipment or one of its peripheral devices. If the equipment
causes interference to radio or television reception, try to correct the interference by using one or more
of the following measures:
•Turn the television or radio antenna until the interference stops.
•Move the equipment to one side or the other of the television or radio.
•Move the equipment farther away from the television or radio.
•Plug the equipment into an outlet that is on a different circuit from the television or radio. (That is,
make certain the equipment and the television or radio are on circuits controlled by different circuit
breakers or fuses.)
•Modifications to this product not authorized by Cisco Systems, Inc. could void the FCC approval
and negate your authority to operate the product.
Safety Guidelines
This section provides safety guidelines you should follow when working with any equipment that
connects to electrical power or telephone wiring.

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JT2 Port Adapter Installation Prerequisites
Safety Warnings
Safety warnings appear throughout this publication in procedures that, if performed incorrectly, might
harm you. A warning symbol precedes each warning statement.
Warning This warning symbol means danger. You are in a situation that could cause bodily injury. Before you
work on any equipment, be aware of the hazards involved with electrical circuitry and be familiar
with standard practices for preventing accidents. To see translations of the warnings that appear in
this publication, refer to the Regulatory Compliance and Safety Information document that
accompanied this device.
Waarschuwing
Dit waarschuwingssymbool betekent gevaar. U verkeert in een situatie die lichamelijk letsel kan
veroorzaken. Voordat u aan enige apparatuur gaat werken, dient u zich bewust te zijn van de bij
elektrische schakelingen betrokken risico's en dient u op de hoogte te zijn van standaard
maatregelen om ongelukken te voorkomen. Voor vertalingen van de waarschuwingen die in deze
publicatie verschijnen, kunt u het document Regulatory Compliance and Safety Information
(Informatie over naleving van veiligheids- en andere voorschriften) raadplegen dat bij dit toestel is
ingesloten.
Varoitus
Tämä varoitusmerkki merkitsee vaaraa. Olet tilanteessa, joka voi johtaa ruumiinvammaan. Ennen
kuin työskentelet minkään laitteiston parissa, ota selvää sähkökytkentöihin liittyvistä vaaroista ja
tavanomaisista onnettomuuksien ehkäisykeinoista. Tässä julkaisussa esiintyvien varoitusten
käännökset löydät laitteen mukana olevasta Regulatory Compliance and Safety Information
-kirjasesta (määräysten noudattaminen ja tietoa turvallisuudesta).
Attention
Ce symbole d'avertissement indique un danger. Vous vous trouvez dans une situation pouvant causer
des blessures ou des dommages corporels. Avant de travailler sur un équipement, soyez conscient
des dangers posés par les circuits électriques et familiarisez-vous avec les procédures couramment
utilisées pour éviter les accidents. Pour prendre connaissance des traductions d’avertissements
figurant dans cette publication, consultez le document Regulatory Compliance and Safety
Information (Conformité aux règlements et consignes de sécurité) qui accompagne cet appareil.
Warnung
Dieses Warnsymbol bedeutet Gefahr. Sie befinden sich in einer Situation, die zu einer
Körperverletzung führen könnte. Bevor Sie mit der Arbeit an irgendeinem Gerät beginnen, seien Sie
sich der mit elektrischen Stromkreisen verbundenen Gefahren und der Standardpraktiken zur
Vermeidung von Unfällen bewußt. Übersetzungen der in dieser Veröffentlichung enthaltenen
Warnhinweise finden Sie im Dokument Regulatory Compliance and Safety Information
(Informationen zu behördlichen Vorschriften und Sicherheit), das zusammen mit diesem Gerät
geliefert wurde.
Avvertenza
Questo simbolo di avvertenza indica un pericolo. La situazione potrebbe causare infortuni alle
persone. Prima di lavorare su qualsiasi apparecchiatura, occorre conoscere i pericoli relativi ai
circuiti elettrici ed essere al corrente delle pratiche standard per la prevenzione di incidenti. La
traduzione delle avvertenze riportate in questa pubblicazione si trova nel documento Regulatory
Compliance and Safety Information (Conformità alle norme e informazioni sulla sicurezza) che
accompagna questo dispositivo.

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JT2 Port Adapter Installation Prerequisites
Electrical Equipment Guidelines
Follow these basic guidelines when working with any electrical equipment:
•Before beginning any procedures requiring access to the chassis interior, locate the emergency
power-off switch for the room in which you are working.
•Disconnect all power and external cables before moving a chassis.
•Do not work alone when potentially hazardous conditions exist.
•Never assume that power has been disconnected from a circuit; always check.
•Do not perform any action that creates a potential hazard to people or makes the equipment unsafe;
carefully examine your work area for possible hazards such as moist floors, ungrounded power
extension cables, and missing safety grounds.
Telephone Wiring Guidelines
Use the following guidelines when working with any equipment that is connected to telephone wiring or
to other network cabling:
•Never install telephone wiring during a lightning storm.
•Never install telephone jacks in wet locations unless the jack is specifically designed for wet
locations.
•Never touch uninsulated telephone wires or terminals unless the telephone line has been
disconnected at the network interface.
Advarsel
Dette varselsymbolet betyr fare. Du befinner deg i en situasjon som kan føre til personskade. Før du
utfører arbeid på utstyr, må du vare oppmerksom på de faremomentene som elektriske kretser
innebærer, samt gjøre deg kjent med vanlig praksis når det gjelder å unngå ulykker. Hvis du vil se
oversettelser av de advarslene som finnes i denne publikasjonen, kan du se i dokumentet Regulatory
Compliance and Safety Information (Overholdelse av forskrifter og sikkerhetsinformasjon) som ble
levert med denne enheten.
Aviso
Este símbolo de aviso indica perigo. Encontra-se numa situação que lhe poderá causar danos
físicos. Antes de começar a trabalhar com qualquer equipamento, familiarize-se com os perigos
relacionados com circuitos eléctricos, e com quaisquer práticas comuns que possam prevenir
possíveis acidentes. Para ver as traduções dos avisos que constam desta publicação, consulte o
documento Regulatory Compliance and Safety Information (Informação de Segurança e Disposições
Reguladoras) que acompanha este dispositivo.
¡Advertencia!
Este símbolo de aviso significa peligro. Existe riesgo para su integridad física. Antes de manipular
cualquier equipo, considerar los riesgos que entraña la corriente eléctrica y familiarizarse con los
procedimientos estándar de prevención de accidentes. Para ver una traducción de las advertencias
que aparecen en esta publicación, consultar el documento titulado Regulatory Compliance and
Safety Information (Información sobre seguridad y conformidad con las disposiciones
reglamentarias) que se acompaña con este dispositivo.
Varning!
Denna varningssymbol signalerar fara. Du befinner dig i en situation som kan leda till personskada.
Innan du utför arbete på någon utrustning måste du vara medveten om farorna med elkretsar och
känna till vanligt förfarande för att förebygga skador. Se förklaringar av de varningar som förkommer
i denna publikation i dokumentet Regulatory Compliance and Safety Information (Efterrättelse av
föreskrifter och säkerhetsinformation), vilket medföljer denna anordning.

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What Is the JT2 Port Adapter?
•Use caution when installing or modifying telephone lines.
Preventing Electrostatic Discharge Damage
Electrostatic discharge (ESD) damage, which can occur when electronic cards or components are
improperly handled, results in complete or intermittent failures. Port adapters and processor modules
consist of printed circuit boards that are fixed in metal carriers. Electromagnetic interference (EMI)
shielding and connectors are integral components of the carrier. Although the metal carrier helps to
protect the board from ESD, use a preventive antistatic strap during handling.
Following are guidelines for preventing ESD damage:
•Always use an ESD wrist or ankle strap and ensure that it makes good skin contact.
•Connect the equipment end of the strap to an unfinished chassis surface.
•When installing a component, use any available ejector levers or captive installation screws to
properly seat the bus connectors in the backplane or midplane. These devices prevent accidental
removal, provide proper grounding for the system, and help to ensure that bus connectors are
properly seated.
•When removing a component, use any available ejector levers or captive installation screws to
release the bus connectors from the backplane or midplane.
•Handle carriers by available handles or edges only; avoid touching the printed circuit boards or
connectors.
•Place a removed component board-side-up on an antistatic surface or in a static shielding container.
If you plan to return the component to the factory, immediately place it in a static shielding
container.
•Avoid contact between the printed circuit boards and clothing. The wrist strap only protects
components from ESD voltages on the body; ESD voltages on clothing can still cause damage.
•Never attempt to remove the printed circuit board from the metal carrier.
Caution For safety, periodically check the resistance value of the antistatic strap. The measurement should be
between 1 and 10 megohms.
What Is the JT2 Port Adapter?
PA-2JT2 (see ) is a port adapter used on the VIP2 in the Cisco 7500 series routers, and in Cisco 7000
series routers using the RSP7000 and RSP7000CI. The JT2 port adapter is available as a spare part:
Product Number PA-2JT2=.
Figure 1 PA-2JT2, Two-Port JT2 Port Adapter (Front Panel View)
ENABLED
AIS RAI LOS AIS RAI LOS
JT2
H9369
TX0 RX0 TX1 RX1

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What Is the JT2 Port Adapter?
Following are JT2 port adapter features and capabilities:
•Each JT2 interface port consists of two coaxial, BNC connectors.
•Provides two data terminal equipment (DTE), synchronous serial interface ports, which are
compatible with and specified by G.703a, and which permit Cisco 7000 series and Cisco 7500 series
routers to communicate over a High Speed Digital 6.3 MHz (HSD 6.3) leased line service (specified
in ITU Recommendation G.704).
•Uses bipolar with 8-zero substitution (B8ZS) encoding.
•Supports cyclic redundancy check (CRC). (Refer to the section “Configuring CRC5” on page 18.)
•Operates at 6.312 Mbps, with 50-percent pulse-width B8Zs encoding.
•Provides an internal fixed clock rate on each JT2 interface port of 6.144 Mbps (not configurable).
The JT2 interfaces automatically use the internal clock for data transmission if no external clock is
detected. When a JT2 interface is configured with the clock source internal command, external
devices will return this clock on the JT2 interface’s receive line; therefore, all clocking is properly
synchronized. (Refer to the section “Using Software Configuration Commands Specific to the JT2
Port Adapter” on page 22
•Provides the functions needed to frame a wideband payload to ITU G.704 and the Nippon Telegram
and Telephone Corporation (NTT)-specified 6.144-Mbps frame format.
•Designed to conform with the following emissions standards: FCC Class Limits (FCC 47 CFR
Part 15, Subpart B), EN55022 Class Limits, and the Japanese Voluntary Control Council for
Interference (VCCI) and CISPR 22 emission standards.
•Designed to conform with the following safety standards: UL 1950 D3 Dev., CSA 22.2 No. 950, and
TUV-IEC 950.
•Received Approval Number N97-K013-0 from the Japan Approvals Institute for
Telecommunications Equipment (JATE)
Port Adapter Locations on the VIP2
shows a VIP2 with two installed port adapters. shows a VIP2-50 with two installed port adapters. With
the VIP2 oriented as shown, the left port adapter is in port adapter slot 0, and the right port adapter is in
port adapter slot 1.
Port adapters have handles that allow for easy installation and removal; however, they are occasionally
not shown in this publication to highlight port adapter faceplate detail.
In the Cisco 7000, Cisco 7507, and Cisco 7513 chassis the VIP2 is installed vertically. In the Cisco 7010
and Cisco 7505 chassis the VIP2 is installed horizontally. There are no interface processor or port
adapter slot restrictions for the VIP2 and JT2 port adapter.

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What Is the JT2 Port Adapter?
Figure 2 Two Port Adapters on the VIP2-40 (Horizontal Orientation Shown)
Figure 3 Two Port Adapters on a VIP2-50 (Horizontal Orientation Shown)
JT2 Port Adapter LEDs
The JT2 port adapter (see ) contains the enabled LED, which is standard on all port adapters; this green
LED goes on after system initialization to indicate that the JT2 port adapter has been enabled for
operation.
H6448
DRAM
SIMMs
Port adapter
in slot 0
Port adapte
r
in slot 1
SRAM
DIMM U5
CPU Boot ROM
Bus connector
U6
U4 U2
Bus connector
SRAM
daughter
card
Port adapter
in slot 0
Port
adapter
in slot 1
DRAM DIMM
H10447
CPU
Boot ROM

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What Is the JT2 Port Adapter?
Figure 4 LEDs on the JT2 Port Adapter (Partial Front-Panel View)
The following conditions must be met before the enabled LED goes on:
•The JT2 port adapter is correctly connected and receiving power.
•The VIP2 contains a valid microcode version that has been downloaded successfully.
•The bus recognizes the VIP2 attached to the backplane.
If any of these conditions is not met, or if the initialization fails for other reasons, the enabled LED
does not go on. The JT2 port adapter has three additional status LEDs for each JT2 port, which are
labeled and function as follows:
•AIS—This red alarm indication signal LED indicates physical layer AIS when all ones are detected
in the received bit stream.
•RAI—This red remote alarm indication LED indicates the presence of 16 or more repeating RAI bit
patterns (1111111100000000) present on the receive data channel. Recovery occurs when four or
more consecutive patterns occur, which are not the RAI pattern received.
•LOS—This red loss of signal LED indicates that a loss of signal has occurred on the receive data
line when input data is zero for 20–32 consecutive clock cycles. Recovery occurs when the receive
signal returns.
JT2 Port Adapter Interface Connectors and Cables
The interface connectors on the JT2 port adapter are coaxial BNC types, with one connector/cable for
transmit (TX) and one for receive (RX) for each interface port. Each BNC connection requires an
external B-type or C-type DSU (with external grounding capability), with an optical fiber output, and
that uses 75-ohm BNC terminations. (Cisco Systems does not supply 75-ohm coaxial cables; they are
available from commercial cable vendors.)
Caution Your coaxial cable’s loss must be less than 6 dB when using maximum cable lengths. To prevent
problems, you must check your 75-ohm coaxial cable’s specifications when long cable lengths are
required to connect the JT2 port adapter to your DSU. Unbalanced JT2 interfaces allow for a longer
maximum cable length than those specified for balanced circuits. Ideally, the maximum cable length for
unbalanced, 75-ohm coaxial cable is 1,968.5 feet (600 meters).
Note The 75-ohm coaxial BNC connections must conform to JIS C5412-1976 high-frequency, coaxial
C02-type connectors, which are equivalent to MIL C 3608 BNC connectors and coaxial cables. The
cables must be unbalanced, 75-ohm (± 5% at 1 MHz) coaxial cables.
You must install a ferrite sleeve (also called a common-mode choke) on each 75-ohm coaxial cable to
reduce the effects of electro-magnetic interference (EMI). (Cisco Systems supplies four ferrite sleeves
with your JT2 port adapter; one ferrite sleeve for each of four 75-ohm coaxial cables you can attach to
PA-2JT2.)
ENABLED
AIS RAI LOS AIS RAI LOS
H9371

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What Is the JT2 Port Adapter?
Note Attach the ferrite sleeve on the end of the coaxial cable nearest the PA-2JT2, as close to the BNC
connector as possible. (See .)
Caution The ferrite sleeve is a required component for proper system operation.
Figure 5 Attaching the Ferrite Sleeve around a Coaxial Cable
shows the typical 75-ohm coaxial cable you should use with PA-2JT2. Use only this type cable for all
PA-2JT2 connections. Use one 75-ohm coaxial cable for each PA-2JT2 connection: RX0, TX0, RX1, and
TX1.
Figure 6 75-Ohm Coaxial Cable with Ferrite Sleeve Attached
The pinout and signal descriptions for the BNC connectors on the JT2 port adapter are as follows:
•Transmit (TX) tip and TX shield, for the 75-ohm coaxial cables that attach to the TX0 and TX1 BNC
connectors
•Receive (RX) tip and RX shield, for the 75-ohm coaxial cables that attach to the RX0 and RX1 BNC
connectors
JT2 Frame Format Description
Japan T2 (JT2) is a 6.312 kilobits-per-second (kbps) line format specified in ITU Recommendation
G.704, and described in the Japanese NTT document Technical Reference for High-Speed Digital Leased
Circuit Services.
A frame consists of 789 bits, and the frame repetition rate is 8 KHz, for a frame duration of 125
microseconds. There are four frames in a multiframe. In each frame, there are 98, 8-bit time slots (bit 1
through bit 784), starting with bit 1 in time slot 1 (TS1).
H10509
Ferrite sleeve Coaxial cable
with ferrite sleeve
Ferrite sleeve
To PA-2JT2 To DSU
H10510

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VIP2 and the JT2 Port Adapter
Note Time slots 1 to 96 are used for the data payload, while time slots 97 and 98 are used for maintenance
signaling by the DSU, the terminal equipment (TE), the network termination equipment (NT), or the line
termination equipment (LT).
The last five bits of the frame, bit 785 through bit 789, are called the F-bits. The F-bits contain the frame
and multiframe alignment signal, which consists of nine bits (110010100) carried in the first two frames
of the multiframe.
VIP2 and the JT2 Port Adapter
This section describes the JT2 port adapter and its use with the VIP2.
The following sections provide additional information specific to the JT2 port adapter and its use on the
VIP2 in Cisco 7000 series and Cisco 7500 series routers:
•Installing or Replacing a Port Adapter on a VIP2, page 13
•Attaching JT2 Port Adapter Interface Cables, page 14
•Configuring the JT2 Interfaces, page 16
shows a VIP2-40 with two JT2 port adapters in port adapter slots 0 and 1. Port adapters can be installed
in either (or both) port adapter slot 0 or port adapter slot 1. You can install VIP2s in any interface
processor slots in your Cisco 7500 series or Cisco 7000 series router.
Figure 7 VIP2-40 with Two JT2 Port Adapters (Horizontal Orientation Shown)
H9370
ENABLED
AIS RAI LOS AIS RAI LOS
JT2
TX0 RX0 TX1 RX1
PA-2JT2 in
port adapter
slot 0
PA-2JT2 in
port adapter
slot 1
Port adapter
handles not
shown
Bus connector
DRAM
SIMMs
SRAM
DIMM U5
CPU
U6
U2
U4
Boot ROM
ENABLED
AIS RAI LOS AIS RAI
JT2
TX0 RX0 TX1 RX1
AIS RAI LOS

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VIP2 and the JT2 Port Adapter
Note Port adapters and VIP2 carriers have handles attached, but these handles are occasionally not shown in
this publication to allow a full view of detail on each port adapter faceplate.
shows a VIP2-50 with two JT2 port adapters installed in port adapter slots 0 and 1.
Figure 8 VIP2-50 with Two JT2 Port Adapters (Horizontal Orientation Shown)
Note If a blank port adapter is installed on the VIP2 in which you want to install a new port adapter, you must
first remove the VIP2 from the chassis, then remove the blank port adapter.
Caution To prevent system problems, do not remove port adapters from the VIP2 motherboard or attempt to
install other port adapters on the VIP2 motherboard while the system is operating. To install or replace
port adapters, first remove the VIP2 from its interface processor slot.
When only one port adapter is installed on a VIP2, a blank port adapter must fill the empty slot to allow
the VIP2 and router chassis to conform to electromagnetic interference (EMI) emissions requirements,
and so that air flows through the chassis properly. If you plan to install a new port adapter, you must first
remove the blank port adapter.
Bus connector
SRAM
daughter
card
Boot ROM CPU
SDRAM DIMM
H11224
Port adapter handles not shown
PA-2JT2 in
port adapter
slot 0
PA-2JT2 in
port adapter
slot 1
ENABLED
AIS RAI LOS AIS RAI LOS
JT2
TX0 RX0 TX1 RX1
ENABLED
AIS RAI LOS AIS RAI
JT2
TX0 RX0 TX1 RX1
AIS RAI LOS

14
PA-2JT2 6.3-MHz Serial Port Adapter Installation and Configuration
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VIP2 and the JT2 Port Adapter
Note For specific VIP2 model requirements for the JT2 port adapter, refer to the section “Software
and Hardware Prerequisites” on page 3.
Step 1
Step 2 Second-Generation Versatile Interface Processor (VIP2) Installation and Configuration
Caution
Step 3 Carefully slide the new port adapter into the port adapter slot until the connector on the port adapter is
completely mated with the connector on the motherboard. (See .)
Second-Generation Versatile Interface Processor (VIP2) Installation and Configuration
Attaching JT2 Port Adapter Interface Cables
The 75-ohm coaxial cable (see ) required for the connections to PA-2JT2 are not available from
Cisco Systems; they are available from commercial cable vendors. Use only 75-ohm coaxial cables for
all PA-2JT2 connections. (For specific cable requirements, refer to the section “JT2 Port Adapter
Interface Connectors and Cables” on page 10.)
Note We recommend that you attach the ferrite sleeves included with PA-2JT2 to all 75-ohm coaxial cables
you plan to use for your PA-2JT2 connections. Attach each ferrite sleeve as close to the port adapter end
of each 75-ohm coaxial cable as possible.
Figure 9 75-Ohm Coaxial Cable with Ferrite Sleeve Attached
Each E1-G.703/G.704 interface requires separate receive and transmit connections to an external B-type
or C-type DSU. A DSU is available from outside vendors.
Use the following procedure to connect the 75-ohm coaxial cables to the JT2 port adapter:
Step 1 Attach the 75-ohm coaxial cables directly to the BNC ports on the JT2 port adapter. Attach one end of
a cable to the port labeled TX0 and one end of a second cable to the port labeled RX0. (See .)
Ferrite sleeve
To PA-2JT2 To DSU
H10510

15
PA-2JT2 6.3-MHz Serial Port Adapter Installation and Configuration
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VIP2 and the JT2 Port Adapter
Figure 10 Connecting 75-Ohm Coaxial BNC Cables (Horizontal Orientation Shown)
Note Older A-type DSUs are not supported with PA-2JT2.
Step 2 Referring to , attach the network ends of your two 75-ohm coaxial cables to your external DSU as
follows:
– Attach the coaxial cable from the JT2 port adapter’s TX0 port to the RX port on your external
DSU.
– Attach the coaxial cable from the JT2 port adapter’s RX0 port to the TX port on your external
DSU.
Caution To prevent system problems and to maintain the proper connection sequences (PA-2JT2’s RX port to the
DSU’s TX port and PA-2JT2’s TX port to the DSU’s RX port), connect the RX and TX ports on the JT2
port adapter as indicated in Steps 1 and 2.
Step 3 Make the appropriate setting on your DSU to establish an external ground. (See .) Remember that the
JT2 port adapter’s TX and RX connections are grounded at the router-chassis side.
Caution To prevent system grounding and signal problems, your DSU must be set to accept an external ground
because the JT2 port adapter’s TX and RX connections are grounded at the router-chassis side.
ENABLED
AIS RAI LOS AIS
RAI
LOS
JT2
H9372
TX0 RX0 TX1 RX1
To DSU's
RX port
BNC cables
To DSU's
TX port

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PA-2JT2 6.3-MHz Serial Port Adapter Installation and Configuration
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VIP2 and the JT2 Port Adapter
Figure 11 Connecting 75-Ohm Coaxial BNC Cables to a DSU and Setting the DSU’s External Ground
Step 4 Repeat Steps 1 through 3 for the additional JT2 interface as required.
This completes the procedure for attaching cables to the JT2 port adapter and an external B-type or
C-type DSU.
Configuring the JT2 Interfaces
If you installed a new JT2 port adapter or if you want to change the configuration of an existing interface,
you must enter configuration mode using the configure command. If you replaced a JT2 port adapter
that was previously configured, the system will recognize the new JT2 interfaces and bring them up in
their existing configuration.
After you verify that the new JT2 port adapter is installed correctly (the enabled LED goes on), use the
privileged-level configure command to configure the new interfaces. Be prepared with the information
you will need, such as the following:
•Protocols you plan to route on each new interface
•Internet protocol (IP) addresses if you plan to configure the interfaces for IP routing
•Whether the new interfaces will use bridging
For a summary of the configuration options available and additional instructions for configuring the JT2
interfaces on the JT2 port adapter, refer to the appropriate configuration publications listed in the section
“Related Documentation” on page 2.
The configure command requires privileged-level access to the EXEC command interpreter, which
usually requires a password. Contact your system administrator if necessary to obtain EXEC-level
access.
Interface Processor Slot, Port Adapter Slot, and JT2 Interface Port Numbering
This section describes how to identify interface processor slot, port adapter slot, and interface port
numbers.
H9701
DSU
External
Ground
Internal
Ground TX RX
Ensure that external ground is
selected on your DSU
To JT2 port
adapter's TX port
To JT2 port
adapter's RX port
BNC cables

17
PA-2JT2 6.3-MHz Serial Port Adapter Installation and Configuration
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VIP2 and the JT2 Port Adapter
Note Although the processor slots in the seven-slot Cisco 7000 and Cisco 7507 and 13-slot Cisco 7513 are
vertically oriented and those in the five-slot Cisco 7010 and Cisco 7505 are horizontally oriented, all
models use the same method for slot and port numbering.
In the router, physical port addresses specify the actual physical location of each interface port on the
router interface processor end. (See .) This address is composed of a three-part number in the format
interface processor slot number/port adapter number/interface port number, as follows:
•The first number identifies the interface processor slot in which the JT2-equipped VIP2 is installed
(as shown in the example system in ).
•The second number identifies the physical port adapter number on the VIP2, and is either 0 or 1.
•The third number identifies the interface ports on the JT2 port adapter, which are always numbered
as 0 and 1. (Each individual interface port has two BNC connections, labeled RX and TX.)
Interface ports on the JT2-equipped VIP2 maintain the same addresses regardless of whether other
interface processors are installed or removed. However, when you move a VIP2 to a different slot, the
first number in the address changes to reflect the new interface processor slot number.
shows the port adapter slots and interface ports of a sample Cisco 7505 system. The JT2 interface
addresses on a JT2 port adapter in the first port adapter slot in interface processor slot 3, would be 3/0/0
and 3/0/1, from left to right. The JT2 interfaces on a JT2 port adapter in port adapter slot 1 would be
numbered 3/1/0 and 3/1/1, from left to right.
Note If you remove the JT2-equipped VIP2 from interface processor slot 3 and install it in interface processor
slot 2, the addresses of those same ports become 2/0/0 and 2/0/1, respectively, and 2/1/0 and 2/1/1,
respectively.
Figure 12 JT2 Interface Port Address Example (Cisco 7505 Shown)
You can identify interface ports by physically checking the slot/port-adapter/interface port location on
the back of the router or by using show commands to display information about a specific interface or
all interfaces in the router.
H9373
Slot 0
Slot 1
Slot 2
Slot 3
Interface
processor
slots
EJECT
SLOT0
SLOT1
NORMAL
CPUHALT
RESET
CONSOLE
ROUTE SWITCHPROCESSOR
JT2 port adapter
(port addresses 3/0/0 and 3/0/1)
JT2 port adapter
(port addresses 3/1/0 and 3/1/1)
ENABLED
AIS
RAI
LOS
AIS
RAI
LOS
JT2
TX0
RX0
TX1
RX1
ENABLED
AIS
RAI
LOS
AIS
RAI
LOS
JT2
TX0
RX0
TX1
RX1

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VIP2 and the JT2 Port Adapter
Configuring an Interface
This section describes a basic configuration. At any time you can exit the privileged level and return to
the user level by entering disable at the prompt as follows:
Router# disable
Router>
In the following basic configuration procedure, press the Return key after each step unless otherwise
noted:
Step 1 At the privileged-level prompt, enter configuration mode and specify that the console terminal will be
the source of the configuration subcommands as follows:
Router# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#
Step 2 At the prompt, specify the first interface to configure by entering the subcommand interface, followed
by the type (serial)and slot/port-adapter/interface (interface processor slot number). The example that
follows is for the first interface of the first port adapter on a JT2 port adapter in interface processor
slot 1:
Router(config)# interface serial 1/0/0
Step 3 If IP routing is enabled on the system, you can assign an IP address and subnet mask to the interface
with the ip address configuration subcommand, as in the following example:
Router(config-int)# ip address 1.1.1.10 255.255.255.0
Step 4 Add any additional configuration subcommands required to enable routing protocols and set the
interface characteristics.
Step 5 Change the shutdown state to up and enable the interface as follows:
Router(config-int)# no shutdown
Step 6 Configure additional interfaces as required.
Step 7 When you have included all of the configuration subcommands to complete the configuration, press
Ctrl-Z to exit configuration mode.
Step 8 Write the new configuration to nonvolatile memory as follows:
Router# copy running-config startup-config
[OK]
Router#
To check the interface configuration using show commands, proceed to the section “Checking the
Configuration.”
Configuring CRC5
For data transmission at JT2 (6.312 Mbps), the G.704 standard suggests a 5-bit CRC. (Refer to ITU
Recommendation G.704 for the definition of CRC5.)

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VIP2 and the JT2 Port Adapter
To enable CRC5 on the JT2 interfaces, specify the slot and port address of the interface and the number
of bits to use in the CRC (using crc 32), followed by the command crc bits 5. Press Ctrl-Z after altering
the configuration and before exiting configuration mode.
The example that follows shows how to enable CRC5 generation on a JT2 interface and also how to set
the CRC size to 32 bits; the example refers to JT2 interface 0 on the first JT2 port adapter on a VIP2 in
interface processor slot 3:
Router# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)# interface serial 3/0/0
Router(config-int)# crc 32
Router(config-int)# crc bits 5
Router(config-int)# ^Z
To disable CRC5 and return to the default of no CRC error checking, specify
the slot and port address and use the no crc bits 5 command.
Checking the Configuration
After configuring the new interface, use the show commands to display the status of the new interface
or all interfaces, and use the ping command to check connectivity.
Using show Commands to Verify the New Interface Status
The following steps use show commands to verify that the new interfaces are configured and operating
correctly.
Step 1 Display the system hardware configuration with the show version command to ensure that the list
includes the new interfaces.
Step 2 Display all the current interface processors and their interfaces with the show controllers cbus
command. Verify that the new JT2 port adapter appears in the correct slot.
Step 3 Specify one of the new interfaces with the show interfaces type slot/port-adapter/interface command
and verify that the first line of the display specifies the interface with the correct slot number. Also
verify that the interface and line protocol are in the correct state: up or down.
Step 4 Display the protocols configured for the entire system and specific interfaces with the show protocols
command. If necessary, return to configuration mode to add or remove protocol routing on the system
or specific interfaces.
Step 5 Display the running configuration file with the show running-config command. Display the
configuration stored in NVRAM using the show startup-config command. Verify that the
configuration is accurate for the system and each interface.
If the interface is down and you configured it as up, or if the displays indicate that the hardware is not
functioning properly, ensure that the network interface is properly connected and terminated. If you still
have problems bringing the interface up, contact a service representative for assistance.
Using show Commands to Display Interface and System Information
To display information about a specific interface, use the show interfaces command with the interface
type and port address in the format show interfaces [type slot/port-adapter/port].

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VIP2 and the JT2 Port Adapter
With the show interfaces [type slot/port-adapter/port]command, use arguments such as the interface
type (serial) and the slot, port adapter, and port numbers (slot/port-adapter/port) to display information
about a specific JT2 interface.
The following example shows all of the information specific to the first JT2 interface port (interface port
0) in interface processor slot 3, port adapter slot 0:
Router# sh int serial 3/0/0
Serial3/0/0 is up, line protocol is up
Hardware is cyBus Serial
Internet address is 1.0.0.1/8
MTU 1500 bytes, BW 6312 Kbit, DLY 20000 usec, rely 255/255, load 26/255
Encapsulation HDLC, loopback not set, keepalive not set
Last input 00:04:31, output 00:04:31, output hang never
Last clearing of “show interface” counters 00:06:07
Queueing strategy: fifo
Output queue 0/40, 0 drops; input queue 0/75, 0 drops
5 minute input rate 162000 bits/sec, 8 packets/sec
5 minute output rate 162000 bits/sec, 8 packets/sec
20005 packets input, 20080520 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
20005 packets output, 20080520 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
0 cv errors, 0 crc5 errors, 0 frame errors
rxLOS inactive, rxLOF inactive, rxPAIS inactive
rxAIS inactive, rxRAI inactive, rxHBER inactive
The following counters appear in the output of the show interfaces serial command:
•cv errors—B8ZS/B6ZS coding violation counter
•crc5 errors—CRC5 error counter
•frame errors—framing error counter
The following alarm indicators also appear in the output of the show interfaces serial command:
•rxLOS—receive loss of signal alarm
•rxLOF—receive loss of frame alarm
•rxPAIS—receive payload alarm indication signal (AIS)
•rxAIS—receive physical AIS
•rxRAI—receive remote alarm indication signal
•rxHBER—receive high bit error rate alarm
For complete command descriptions and examples, refer to the publications listed in the section “Related
Documentation” on page 2.
The show version command displays the configuration of the system hardware (the number and type of
each interface processor type installed), the software version, the names and sources of configuration
files, and the boot images. Following is an example of the show version command:
Router# sh version
Cisco Internetwork Operating System Software
IOS (tm) GS Software (RSP-JV-M), Version 11.1(12)CA1 [biff 137]
Synced to mainline version: 11.1(8)
Copyright (c) 1986-1997 by cisco Systems, Inc.
Compiled Sat 10-May-97 19:19 by biff
Image text-base: 0x600108A0, data-base: 0x609DA000