3com IntelliJack NJ100 Frequently Asked Questions Manual

Brand: 3com

Model: IntelliJack NJ100

Category: Network switches

Type: Frequently Asked Questions Manual

3Com IntelliJack NJ100 is a versatile networking device offering a range of capabilities to enhance your network connectivity. It functions as a four-port, 10/100 wire-speed switch, providing fast and reliable data transfer speeds. The device also includes one switched 10/100 uplink port, allowing for flexible network expansion.

FREQUENTLY ASKED QUESTIONS

3Com

NJ100 Network Jack

Product Specifications

Is this a hub?

No. The 3Com

NJ100 Network Jack is

a four-port, 10/100 wire-speed switch

with one switched 10/100-uplink port

in the back of the unit. The five inte-

grated independent Fast Ethernet

transceivers are fully compliant with

IEEE 802.3 and 802.3u standards.

What colors are available?

The 3Com NJ100 Network Jack comes

in two colors:

• Black, 3CNJ100-BLK

• Cream, 3CNJ100-CRM

Which adapter plates are included

with the 3Com NJ100 Network Jack?

The single-unit pack includes three

adapter plates—blank, Avaya, and

Panduit—that match the network

jack color, black or cream. The

20-unit packs do not come with

adapter plates, which must be

ordered separately. Currently, the

20-unit packs of adapter plates are

only available in cream.

Are the switched ports autosensing

or autonegotiating?

All four switched ports support

IEEE-compliant 10/100 autonegotia-

tion and full duplex or half-duplex

connections.

What switch mode does the 3Com

NJ100 Network Jack utilize?

The 3Com NJ100 Network Jack uses

store-and-forward switch mode. Ethernet

packets from each port are buffered

until the full packet is received. Once

the packet is received, it is forwarded

to any one of the other ports based on

the destination MAC address. The

network jack switch cannot be config-

ured for “cut through” mode.

How many MAC addresses does the

switch table hold?

The 3Com NJ100 Network Jack includes

a high-performance lookup engine with

support for up to 4,096 MAC address

entries. It also includes automatic

learning and aging.

Network Compatibility

Are there compatibility issues with

other networking equipment in the

wiring closet?

No. The 802.3-compliant 3Com NJ100

Network Jack is designed as a client

device. Because it’s an unmanaged

switch, there’s no software to conflict

with your existing management or

networking applications.

Does the 3Com NJ100 Network Jack

support traffic prioritization, QoS,

or multiple VLANs?

No. The 3Com NJ100 Network Jack is

an unmanaged switch, so it doesn’t

deploy 802.1p traffic prioritization,

The cost-saving,

cabling alternative

for IEEE 802.3-

compliant LANs.

3COM

NJ100 NETWORK JACK

Quality of Service (QoS), or 802.1Q

VLANs. However, although it cannot

add VLAN or QoS information to the

frames as they pass through the switch,

the network jack supports any VLAN

or QoS tags the frames contain. Future

versions are expected to support

802.3p traffic prioritization.

VoIP Compatibility

Does the 3Com NJ100 Network Jack

support VoIP?

The 3Com NJ100 Network Jack can

accommodate voice traffic two ways:

In a converged voice and data net-

work environment, an IP phone can

be plugged into one of the 10/100

switched ports. To support Power

over Ethernet, the IP phone must be

plugged into Port #1 of the 3Com

NJ100 Network Jack. For more dis-

cussion of Power over Ethernet and

power forwarding, please review the

Power Sources section of this docu-

ment and the Power Considerations FAQ.

If voice and data networks are wired

separately, you can use one of the

3Com NJ100 Network Jack’s pass-

through ports as the connection point

for the IP phone. The pass-through

port is wired separately from the

switched 10/100 ports—with cable

being pulled and terminated in the

traditional manner.

An additional way to connect voice

and data through the network jack is

by using the pass-through port to

connect your legacy voice system to

the PBX in the telephone room.

Does the 3Com NJ100 Network Jack

adversely affect VoIP quality?

3Com lab tests of the 3Com NJ100

Network Jack indicate that even at

data transfer loads within 98 percent

of capacity, there is no significant

degradation in voice response or

quality—even when the other three

switched ports are actively connected.

Power Sources

Does the 3Com NJ100 Network Jack

require power?

Yes. The 3Com NJ100 Network Jack is

an active device and requires a source

of power, which must be purchased

separately. LEDs on the face indicate

power and LAN connectivity.

How is the 3Com NJ100 Network

Jack powered?

The 3Com NJ100 Network Jack is

options:

3Com Network Jack Single-Port

Power-over-Ethernet Midspan

Solution (3CNJPSE) provides

midspan power to a single 3Com

NJ100 Network Jack. This in-line

power source can be connected to

the network jack at the end-user

location or installed in the wiring

closet. List price: $29.00

3Com Network Jack Multiport

Power-over-Ethernet Midspan

Solution (3CNJPSE24) provides IEEE

802.3af-compatible midspan power

for up to 24 network jacks. It must be

installed in the wiring closet, where it

adds Power over Ethernet to any man-

ufacturer’s switch. This is the optimal

choice for installation convenience.

List price: $1,299.00

3Com Ethernet Power Sources

(3C10220, 3C10222) provide midspan

power for 12 or 24 ports, respectively.

3Com Ethernet Power Sources do not

conform to the proposed 802.3af stan-

dard. These 19-inch, rack-mountable

units were originally designed to

power 3Com NBX

telephone equip-

ment, but can also power 3Com NJ100

Network Jacks with the proper dip-

switch settings. 3C10220 List price:

$1,282.00 3C10222 List price: $1,683.00

Any 802.3af-compliant power-

forwarding device can be used to

provide midspan power for 3Com

NJ100 Network Jacks.

The 3Com

NJ100

Network Jack

supports VoIP

and the proposed

IEEE 802.3af

specification for

Power over Ethernet.

3COM

NJ100 NETWORK JACK

Power over Ethernet

enables the

simultaneous

transmission of

voice and power

over Cat 5 or 5e

cabling.

3Com Network Jack AC Power Supply

(3CNJPSL) provides local power to

a single 3Com NJ100 Network Jack.

List price: $26.00

What is Power over Ethernet?

Power over Ethernet is simply the

transmission of power over an exist-

ing Ethernet cable. It has become the

preferred method for powering wire-

less access points and IP telephone

handsets. The IEEE is currently

developing a standard for Power

over Ethernet, labeled 802.3af.

Has the 802.3af specification been

ratified?

No, however, it is expected to be

ratified in 2002. 3Com is actively

involved with the standard, and the

3Com NJ100 Network Jack complies

with the proposed IEEE 802.3af speci-

fication for Power over Ethernet.

What are the advantages of Power

over Ethernet?

Power over Ethernet offers the follow-

ing benefits:

• Networked devices can obtain

power and data over the same

wiring, streamlining installation

and configuration.

• Power can be supplied over existing

Category 5 or 5e UTP wiring with-

out additional modifications or

requirements to the cabling plant.

• Power can be supplied to networked

devices without relying on end-user

action.

What are the dipswitches used for?

The dipswitches must be set to match

the power source. The default setting

is IEEE 802.3af-compatible Power

over Ethernet. Before setting the dip-

switches, make sure that power to the

3Com NJ100 Network Jack is off. For

specific dipswitch settings, consult

your Installation Guide.

Where are the dipswitches?

Before setting the dipswitches, make

sure that power to the 3Com NJ100

Network Jack is off. The dipswitches

are located on the back, above the

opening for the pass-through connec-

tors. For more information, consult

your Installation Guide.

In a Power-over-Ethernet-capable

network, the 3Com NJ100 Network

Jack can forward power to a device

connected to Port #1. How does

that work?

The 3Com NJ100 Network Jack is

not only designed to be powered by

Power over Ethernet, but it can also

forward power to a device such as an

IP phone that needs it as well. In the

example of the IP phone, you can plug

it into Port #1. If it’s compatible with

the basic standards of the draft 802.3af

Power-over-Ethernet standard—48 V

DC and a resistive power discovery

scheme—the network jack will detect

the phone and forward power to it.

Since the 802.3af standard has not

been ratified, some equipment uses a

pre-standard detection scheme called

capacitive power discovery.

Does Port #1 forward power when

using local AC power supply?

Yes, power forwarding over the unused

pairs on Port #1 happens regardless

of the 3Com NJ100 Network Jack

power source.

Which Power-over-Ethernet

switches are compatible with the

3Com NJ100 Network Jack?

The 3Com NJ100 Network Jack should

be compatible with any Power-over-

Ethernet switch that complies with

the proposed 802.3af Power-over-

Ethernet standard.

This unmanaged

network device is

fully compliant with

BICSI TIA 568A and

TIA 569A cabling

installation

standards.

3COM

NJ100 NETWORK JACK

3Com NBX System and the

3Com Network Jack

Will the 3Com NJ100 Network Jack

forward power to a 3Com NBX

handset if the 3Com Network Jack

Multiport Power-over-Ethernet

Midspan Solution (3CNJPSE24) is

powering the system?

No. The 3Com NJ100 Network Jack

and 3Com Network Jack Multiport

Power-over-Ethernet Midspan Solution

are designed to meet the current

version of the proposed 802.3af

Power-over-Ethernet specification.

As a result, they use a resistive power

discovery scheme. Any device

plugged into it must have a resistive

signature in order to have power for-

warded to it by the 3Com NJ100

Network Jack. Currently, the 3Com

NBX handset does not have a resistive

power discovery scheme.

In addition, the 3Com NBX handset

is designed for a 24 V system. The

802.3af specification is 48 V, as is

the 3Com NJ100 Network Jack. The

only way for an NBX handset to run

through a 3Com NJ100 Network Jack

today is if the handset has its own

local power source.

Are there plans to enable the 3Com

NJ100 Network Jack to power a

3Com NBX handset in the future?

We anticipate that IEEE will ratify

the 802.3af standard. Subsequently,

other networking products will most

likely transition to supporting this

type of Power-over-Ethernet. In the

interim, we are exploring possible

power options.

Traditional Wiring and

Current Installation Practices

What are the standards that govern

cabling in buildings?

TIA 568A and TIA 569A are the basic

standards. BICSI is generally recog-

nized as the governing body for the

professional cabling industry.

Will my cabling remain TIA 568A- and

TIA 569A-compliant after installing

the 3Com NJ100 Network Jack?

Yes. The 3Com NJ100 Network Jack

is a network device that complies

with TIA 568A and TIA 569A stan-

dards. Installing the network jack

terminates the Ethernet connection

to a switch port.

How does this fit with a structured

cabling system?

Connection from a structured cabling

system (SCS) to the 3Com NJ100

Network Jack is no different than

the connection from an SCS to an

Ethernet NIC in a PC. When connect-

ing an SCS and NIC, horizontal

cabling is pulled to the user’s work-

space and terminated to a female

RJ-45. The cable and connector

integrity are tested following TIA-

established methods. An approved

patch cord connects the female RJ-45

to the NIC.

In a similar way, the connection

between an SCS and the network jack

is established with a factory-tested

male-to-male cable. The network jack

presents the same interface back to

the switch as an Ethernet NIC in a PC.

The integrity of the signaling through

the network jack is tested at the fac-

tory and is also verifiable by the

installer using an optional test unit.

The procedure for doing this is estab-

lished as part of the 3Com Approved

Network Jack Installer Program.

Deploying a

network jack can

save up to 60

percent versus

traditional cabling

expansion and port

activation.

3COM

NJ100 NETWORK JACK

Why don't you have a punch-down

connector instead of an RJ-45 uplink

port on the back of the 3Com NJ100

Network Jack?

There are two main reasons why the

3Com NJ100 Network Jack doesn’t

connect to horizontal cabling via an

IDC punch-down. First, the product is

designed to reduce the cost of moves,

adds, or changes as a result of either

reconfiguring cubicles or moving to

another facility. The RJ-45 connection

allows you to easily install and, when

necessary, remove the network jack.

Second, BICSI’s wire test standards

prohibit you from testing the cabling

system through active components. If

you were to punch down the horizon-

tal cabling directly to the back of the

network jack, you would not be able

to test the cabling system according

to the BICSI standard. 3Com is work-

ing to develop a version of the

network jack that will have a punch-

down connection that does not

violate those wire test standards.

Can I daisy-chain multiple 3Com

NJ100 Network Jacks together?

If so, how many?

Although it is possible to daisy-chain

multiple 3Com NJ100 Network Jacks

together, we do not recommend it. A

Power-over-Ethernet solution will not

provide enough power to multiple

network jacks. With local power, you

will be constrained by switching-

topology considerations.

What types of pass-through

connectors do you support?

The adapter plates for the pass-

through connections support Panduit-

or Avaya-brand interface modules, RJ-

11 or RJ-45 connectors.

The 3Com NJ100 Network Jack

single-unit pack includes three

adapter plates—blank, Avaya, and

Panduit. The 20-unit packs do not

come with adapter plates, which

must be ordered separately.

Panduit interface modules:

Single category 3 CJ66BL (black)

module CJ66EI (ivory)

Single category 5 CJ588TBL (black)

module CJ588TEI (ivory)

Single category 5e CJ5E88TBL (black)

module CJ5E88TEI (ivory)

Avaya interface modules:

Single category 3 107321697 (black)

module 107321721 (ivory)

Single category 3/5e 108232695 (black)

module 108232737 (ivory)

Isn’t this more expensive than just

activating another port in my closet?

You cannot get the same functionality

by activating another port in your

closet that you can get from installing a

3Com NJ100 Network Jack. To get the

same number of active connections,

you would have to activate three new

ports in your closet, which is more

expensive than the cost of installing

a single network jack. In a new

installation, it is significantly more

expensive—up to 60 percent—to

deploy a traditional cabling system and

get the same number of active connec-

tions as deploying the network jack.

Competitive Positioning

Are there other products like this on

the market?

The 3Com NJ100 Network Jack is

unique in the networking world. As a

product, it is most often compared to

a desktop hub or switch. As a cabling

solution, it is compared to traditional,

passive-component cabling systems.

Isn’t this more expensive than just

adding a desktop hub or switch?

People ask why they shouldn’t just

buy a desktop hub or switch. A price

comparison between a 3Com NJ100

Network Jack and a desktop hub is

an apples-to-oranges comparison.

3COM

NJ100 NETWORK JACK

Customers

can maximize

existing cabling

infrastructures

and improve the

integration of their

networked devices.

The basic value of the network jack is

that it’s part of the cabling infrastruc-

ture rather than a desktop device. As

a result, it replaces cabling and uses

fewer switch ports—which can save

an organization a tremendous amount

of money. Our studies indicate that

by deploying the 3Com NJ100

Network Jack, you can save up to

$430 over a traditional installation

of four active ports.

Beyond cost savings, what are

the benefits of the 3Com NJ100

Network Jack?

In addition to cost savings, the 3Com

NJ100 Network Jack:

• Prevents the deployment of unau-

thorized desktop devices. Most IT

managers indicate they have prob-

lems with end users introducing

unauthorized desktop devices into

their networks. The 3Com NJ100

Network Jack provides a solution

that gives the end user the added

connectivity but puts control back

in the hands of the IT manager.

• Consolidates voice and data

connections. The 3Com NJ100

Network Jack is VoIP-compatible

in a converged voice/data environ-

ment via its switched ports or in

a separate voice network (VoIP or

legacy analog) via its pass-through

ports. What’s more, it connects all

those functions within a 3" x 5"

space. Desktop hubs and switches

don’t offer this level of functional-

ity within the footprint of a

network jack.

• Minimizes potential disruption. By

making the added connectivity part

of the infrastructure, there is less

chance of the end user accidentally

disrupting the connection. These

disruptions typically prompt phone

calls to IT support. The 3Com NJ100

Network Jack significantly reduces

the costs associated with those calls.

This is especially true in a Power-

over-Ethernet environment.

• Increases the integrity of the net-

work. From a data perspective, this

point is more relevant to desktop

hubs because it reduces the poten-

tial for end users to create loopback

errors. From a power perspective, a

Power-over-Ethernet solution virtu-

ally eliminates the possibility of

power disruption, increasing the

overall integrity of the network.

• Reduces possibility of theft. Free-

standing desktop hubs and switches

are more likely to “grow legs and

walk away” than a 3Com NJ100

Network Jack that is screwed

into the wall.

• Cleans up the desktop area. The

3Com NJ100 Network Jack allows

you to reduce the number of cables

exposed on the desktop.

Sales & Marketing

Who are your customers?

Anyone in a networked environment

who needs to connect more devices

than their number of existing active

connections should consider the 3Com

NJ100 Network Jack. A customer that

deploys network jacks in a new instal-

lation receives the maximum amount of

savings in their network infrastructure

costs. Customers that install network

jacks in their existing installations,

maximize their existing cabling infra-

structure without incurring the high

cost of pulling additional cable.

Customers with limited or fixed IT

budgets can expand connectivity

with the network jacks and free up

resources for other equipment.

What are some specific applications?

Here are a few examples of organiza-

tions and locations that can benefit by

installing 3Com NJ100 Network Jacks:

Education

• Training rooms

• Faculty or administrative offices

• Computer labs

• Dorm rooms

• Libraries

• Group study areas

3COM

NJ100 NETWORK JACK

3Com Corporation, Corporate Headquarters, 5400 Bayfront Plaza, P.O. Box 58145, Santa Clara, CA 95052-8145

To learn more about 3Com solutions, visit

www.3com.com. 3Com is publicly traded on Nasdaq under the symbol COMS.

is a trademark of 3Com Corporation. All other company and product names may be trademarks of their respective

companies. While every effort is made to ensure the information given is accurate, 3Com does not accept liability for

any errors or mistakes which may arise. All specifications are subject to change without notice.

103020-001 04/02

Government

• Federal headquarters

• State offices

• Local offices

Enterprise

• Cubicles

• Conference rooms

• Public areas, such as network

printer rooms

• Work areas for consultants or

temporary workers

• Laboratories

Other

• Hard-to-wire locations, such as

older buildings with asbestos

• Historical buildings

• Tradeshows or event venues

Does the 3Com NJ100 Network Jack

ship with a power supply?

No. There are several different solutions

for powering the 3Com NJ100 Network

Jack. Rather than burdening customers

with the cost of a power solution they

can’t use, we offer a variety of options

so they can choose the power solution

to best fit their needs.

Pricing

Do you offer a discount for

multi-packs?

Yes. The current list price for a single-

unit pack is $140. The current list price

for a 20-pack is $2,600 or $130 per unit.

Where can I buy a 3Com NJ100

Network Jack?

If you have an account with Graybar

Electric Company, Inc., you can pur-

chase directly from them. You can also

purchase 3Com NJ100 Network Jacks

through your local cabling contractor

or value-added reseller. Finally, you can

purchase online at www.3com.com.

Is this available outside of the

United States?

Currently, the 3Com NJ100 Network

Jack is only available in the United

States. We are working to offer it in

other countries as soon as possible.

Warranty Information

When I wire a building, I expect that

cabling infrastructure to last at least 15

years. Does the 3Com NJ100 Network

Jack have a comparable warranty?

The 3Com NJ100 Network Jack has

a Lifetime Limited warranty on hard-

ware repair or replacement. “Lifetime

Limited” means that it is covered

for as long as the customer owns the

product or 5 years after the product is

discontinued, whichever occurs first.

Does the warranty include technical

support?

Phone-based technical support is

available within the U.S. for 90 days

through our toll-free number, 1-800-

527-8677.

We offer around-the-clock, web-based

support at http://support.3com.com,

including product support, service

and warranty information, training,

and software downloads. Also available

through our support page is the 3Com

Knowledgebase. This interactive tool

provides technical product informa-

tion from top 3Com engineers around

the globe.

For additional product information,

such as technical tips, product data

sheets, technology white papers, fre-

quently asked questions (FAQs), and

more, visit www.3com.com.

Are there any 3Com Maintenance

Services available for the 3Com

NJ100 Network Jack?

No maintenance services apply to

this product.

The 3Com

NJ100

Network Jack is

covered by our

Lifetime Limited

warranty.

3com IntelliJack NJ100 Frequently Asked Questions Manual

Brand: 3com

Model: IntelliJack NJ100

Category: Network switches

Type: Frequently Asked Questions Manual

Download PDF

report

3com IntelliJack NJ100 Frequently Asked Questions Manual

3com IntelliJack NJ100 Frequently Asked Questions Manual

Related papers

Other documents