Ntron 712FX4 Series Installation and operating instructions

712FX4
Managed Industrial
Ethernet Switch
User Manual &
Installation
Guide

(Revised 2012-05-01) Page 2 of 163
712FX4 Industrial Ethernet Switch Installation Guide.............................................................................................5
712FX4 Industrial Ethernet Switch Accessories......................................................................................................7
SAFETY WARNINGS...........................................................................................................................................9
SUPPORT:.............................................................................................................................................................9
Installation ...........................................................................................................................................................10
DIN RAIL MOUNTING......................................................................................................................................12
FRONT PANEL (712FX4)...................................................................................................................................13
APPLYING POWER (Top View).........................................................................................................................14
Connecting the Unit..............................................................................................................................................15
Overview of Advanced Features...........................................................................................................................19
Mode of Operation..................................................................................................................................................................19
Port Mirroring .........................................................................................................................................................................19
Port Trunking ..........................................................................................................................................................................19
Quality of Service (QoS).........................................................................................................................................................19
Virtual LAN............................................................................................................................................................................20
Rapid Spanning Tree Protocol ................................................................................................................................................21
SNMP Traps............................................................................................................................................................................21
IGMP Snooping ......................................................................................................................................................................21
N-Ring.....................................................................................................................................................................................22
N-Link.....................................................................................................................................................................................22
CIP ..........................................................................................................................................................................................22
DHCP......................................................................................................................................................................................22
DHCP Client ...........................................................................................................................................................................23
DHCP Relay Agent.................................................................................................................................................................23
DHCP Server...........................................................................................................................................................................23
LLDP.......................................................................................................................................................................................23
Port Security—MAC Address Based......................................................................................................................................23
TROUBLESHOOTING..........................................................................................................................................................24
Web Software Configuration ................................................................................................................................25
Web Management ...................................................................................................................................................................25
Web Management - Home ......................................................................................................................................................26
Administration – System.........................................................................................................................................................28
Administration – SNMP..........................................................................................................................................................32
Administration – Fault ............................................................................................................................................................34
DHCP – Server – Setup Profiles .............................................................................................................................................36
DHCP – Server – Setup IP Maps ............................................................................................................................................38
DHCP – Server – View Bindings............................................................................................................................................43
DHCP – Relay & Local IP - Setup..........................................................................................................................................44
LLDP - Configuration.............................................................................................................................................................47
LLDP - Ports ...........................................................................................................................................................................48
LLDP - Status..........................................................................................................................................................................49
LLDP - Statistics.....................................................................................................................................................................50
Ports – Configuration..............................................................................................................................................................51
Ports – MAC Security – Learning...........................................................................................................................................54
Ports – MAC Security – Authorization List............................................................................................................................55
Ports – MAC Security – Intruder Log.....................................................................................................................................56
Ports – Mirroring.....................................................................................................................................................................57
Ports – Trunking......................................................................................................................................................................59
Ports – QOS.............................................................................................................................................................................60
Statistics – Port Statistics ........................................................................................................................................................62
Statistics – Port Utilization......................................................................................................................................................63
VLAN – Configuration ...........................................................................................................................................................64
Bridging – Aging Time...........................................................................................................................................................66
Bridging – Unicast Addresses.................................................................................................................................................67
Bridging – Multicast Addresses ..............................................................................................................................................69
Bridging – Show MAC by Port...............................................................................................................................................71
RSTP – Configuration.............................................................................................................................................................73
IGMP – Configuration ............................................................................................................................................................77
IGMP – Show Group and Show Router..................................................................................................................................80

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IGMP – RFilter .......................................................................................................................................................................81
N-View – Configuration..........................................................................................................................................................83
N-View – Ports........................................................................................................................................................................84
N-Ring – Configuration ..........................................................................................................................................................86
N-Ring – Advanced Configuration .........................................................................................................................................89
N-Ring – Status.......................................................................................................................................................................91
N-Link – Configuration...........................................................................................................................................................95
N-Link – Status .......................................................................................................................................................................99
CIP – Configuration..............................................................................................................................................................104
CIP – Status...........................................................................................................................................................................105
Firmware/Config – TFTP......................................................................................................................................................106
Support – Web Site and E-mail.............................................................................................................................................107
BPCL – Broadcast Packet Count Limit Configuration .........................................................................................................108
User Management – Adding Users .......................................................................................................................................109
User Management – Removing Users...................................................................................................................................110
LogicalView..........................................................................................................................................................................111
Configuration – Save or Reset...............................................................................................................................................112
Help – Overview ...................................................................................................................................................................114
Help – Administration...........................................................................................................................................................115
Help – DHCP ........................................................................................................................................................................116
Help – LLDP.........................................................................................................................................................................117
Help – Ports...........................................................................................................................................................................118
Help – Statistics.....................................................................................................................................................................119
Help – VLAN........................................................................................................................................................................120
Help – Bridging.....................................................................................................................................................................121
Help – RSTP .........................................................................................................................................................................122
Help – IGMP.........................................................................................................................................................................123
Help – N-View......................................................................................................................................................................124
Help – N-Ring.......................................................................................................................................................................125
Help – N-Link .......................................................................................................................................................................126
Help – CIP.............................................................................................................................................................................127
Help – Firmware/Config .......................................................................................................................................................128
Help – BPCL.........................................................................................................................................................................129
Help – User Management......................................................................................................................................................130
Help – Other..........................................................................................................................................................................131
CLI Commands..................................................................................................................................................132
“?” (Help)..............................................................................................................................................................................132
Logout...................................................................................................................................................................................132
Show, Add, or Delete ARL Entries.......................................................................................................................................133
Configuration Device Operations..........................................................................................................................................134
Show or Set CIP Configuration.............................................................................................................................................135
Save or Reset the Configuration Settings..............................................................................................................................136
Show or Set IGMP Configuration.........................................................................................................................................136
Show or Set Mirror Configuration ........................................................................................................................................137
Show or Set N-Ring Configuration.......................................................................................................................................138
Show or Set N-View Configuration......................................................................................................................................138
Ping a Host............................................................................................................................................................................139
Show or Set Port Configuration ............................................................................................................................................140
Reset the Switch....................................................................................................................................................................141
Show or Set SNMP Configuration........................................................................................................................................141
Show or Clear the Last System Error....................................................................................................................................142
Show System Information.....................................................................................................................................................142
Set or Show the System IP Configuration.............................................................................................................................143
Show or Set System Configuration .......................................................................................................................................144
VLAN Addition and Deletion Example ..............................................................................................................145
VLAN Configuration Examples..........................................................................................................................150
Example 1 – Basic understanding of port-based VLANs......................................................................................................150
Example 2 – Basic understanding of tagged VLANs (Admit – Tagged Only).....................................................................151
Example 3 – Basic understanding of tagged VLANs (Admit – All).....................................................................................152
Example 4 – Basic understanding of Hybrid VLANs ...........................................................................................................153
Example 5 – Basic understanding of Overlapping VLANs...................................................................................................154

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Example 6 – Basic understanding of VLANs with Multicast Filtering.................................................................................155
KEY SPECIFICATIONS (712FX4) ...................................................................................................................156
KEY SPECIFICATIONS (712FX4-HV)............................................................................................................158
Appendix A. XML Settings File Example..........................................................................................................160
N-TRON Limited Warranty................................................................................................................................163

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712FX4 Industrial Ethernet Switch Installation Guide
The N-TRON 712FX4 Industrial Ethernet Switch offers outstanding performance and ease of use. It is
ideally suited for connecting Ethernet enabled industrial and or security equipment and is a fully managed
switch.

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PRODUCT FEATURES
• Full IEEE 802.3 Compliance
• Eight 10/100 BaseTX RJ-45 Ports
• Four 100BaseFX(E) Ports
• Extended Environmental Specifications (Surrounding
Air): -40 to 70 ºC Operating temperature
• ESD and Surge Protection Diodes on all Ports
• Auto Sensing 10/100BaseTX, Duplex, and MDIX
• Offers Rapid Spanning Tree Protocol
• Store & Forward Technology
• Rugged Din-Rail Enclosure
• Onboard Temperature Sensor
• Configuration Backup via optional SD Card
(NTCD-128)
• Redundant Power Inputs
PRODUCT CONFIGURATIONS
• 712FX4-XX-VV and 712FXE4-XX-YY-VV
– Eight 10/100 Base-TX RJ45 Copper Ports
Four 100BaseFX Ports,
Where: XX = ST or SC
YY = 10, 40 or 80 for Singlemode, Blank for Multimode
VV = HV for High voltage, Blank for Standard voltage
E = Singlemode, Blank Otherwise
MANAGEMENT FEATURES
• SNMP v1, v2, v3 and Web Browser Management
• Configuration backup via Optional Configuration Device (NTCD)
• EtherNet/IP™ CIP Messaging
• Detailed Ring Map and Fault Location Charting
• N-Ring™ Technology with ~30ms Healing
• Web Browser Management with detailed ring map and
fault location charting.
• N-View™ OPC Monitoring
• N-Link™ Redundant N-Ring Coupling
• IGMP Auto Configuration and Plug and Play Support
• 802.1Q tag VLAN and Port VLAN
• 802.1p QoS, Port QoS, and DSCP
• LLDP (Link Layer Discovery Protocol)
• Trunk with other N-Tron trunking capable switches over two ports
• Port Mirroring
• 802.1d, 802.1w, 802.1D RSTP (Rapid Spanning Tree Protocol)
• DHCP Client, Server, Option 82 relay, Option 61
• Local Port IP Addressing
• Port Security—MAC Address Based
Copyright, © N-Tron Corp., 2008-2012

(Revised 2012-05-01) Page 7 of 163
712FX4 Industrial Ethernet Switch Accessories
The SD and USB connectors are for temporary connection only. Do not use, connect, or disconnect unless
area is known to be non-hazardous. Connection or disconnection in an explosive atmosphere could result in
an explosion.
NTCD-128
Configuration Device
Ideal for saving, or restoring switch configuration
parameters quickly without the need for a computer or
software. One configuration device per switch is
recommended.
The configuration device is inserted in the back of the 712FX4.

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820 S. University Blvd., Suite 4E
Mobile, AL 36609 USA
All rights reserved. Reproduction, adaptation, or translation without prior written permission from N-Tron
Corp. is prohibited, except as allowed under copyright laws.
Ethernet is a registered trademark of Xerox Corporation. All other product names, company names, logos
or other designations mentioned herein are trademarks of their respective owners.
The information contained in this document is subject to change without notice. N-Tron Corp. makes no
warranty of any kind with regard to this material, including, but not limited to, the implied warranties of
merchantability or fitness for a particular purpose. In no event shall N-Tron Corp. be liable for any
incidental, special, indirect, or consequential damages whatsoever included but not limited to lost profits
arising out of errors or omissions in this manual or the information contained herein.
Warning
Do not perform any services on the unit unless qualified to do so. Do not substitute unauthorized parts or
make unauthorized modifications to the unit.
Do not operate the unit with the top cover removed, as this could create a shock or fire hazard.
Do not block the air vents on the sides or the top of the unit.
Do not operate the equipment in the presence of flammable gasses or fumes. Operating electrical equipment
in such an environment constitutes a definite safety hazard.
Do not operate the equipment in a manner not specified by this manual.

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SAFETY WARNINGS
GENERAL SAFETY WARNINGS
WARNING: If the equipment is used in the manner not specified by N-Tron Corp., the protection
provided by the equipment may be impaired.
LASER SAFETY (Single Mode Fiber Models -40 and -80)
CAUTION: CLASS 1 LASER PRODUCT. Do not stare into the laser!
SUPPORT:
Contact Information
N-Tron Corp.
820 South University Blvd. Suite 4E
Mobile, AL 36609
TEL: [phone]
FAX: [phone]
WEBSITE: www.n-tron.com
E-MAIL: [email protected]
ENVIRONMENTAL SAFETY
WARNING: The unit may become very hot to the touch in high temperature environments, so extreme
caution should be exercised in handling when energized. The unit should be disconnected from power and
allowed to cool for approximately 5 minutes before touching in high temperature applications.
ELECTRICAL SAFETY
Must be powered by a Class 2 source only.
WARNING: Disconnect the power cable before removing the top cover.
WARNING: Do not operate the unit with the any cover removed.
WARNING: Properly ground the unit before connecting anything else to the unit. Units not properly
grounded may result in a safety risk and could be hazardous and may void the warranty. See the grounding
technique section of this user manual for proper ways to ground the unit.

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WARNING: Do not work on equipment or cables during periods of lightning activity.
WARNING: Do not perform any services on the unit unless qualified to do so.
WARNING: Do not block the air vents.
WARNING: Observe proper DC Voltage polarity when installing power input cables. Reversing voltage
polarity can cause permanent damage to the unit and void the warranty.
Hazardous Location Installation Requirements
1.
This equipment is suitable for use in Class I, Div. 2, Groups A, B, C, D or non-hazardous locations
only.
2. WARNING: Explosion Hazard – Substitution of components may impair suitability for Div. 2.
3. WARNING: Explosion Hazard - do not disconnect while circuit is live, unless area is known to be
non-hazardous.
4. WARNING: Explosion Hazard – do not replace the device unless power has been switched off or
the area is known to be non-hazardous.
5. Use 90°C or higher rated Copper wire, (0.22Nm) 2lb/in Tightening torque for field installed
conductors.
Please make sure the 712FX4 Series Ethernet Switch package contains the following items:
1. 712FX4 Series Switch
2. Product CD
Contact your carrier if any items are damaged.
Installation
Read the following warning before beginning the installation:
WARNING
Never install or work on electrical equipment or cabling during periods of lightning activity. Never connect
or disconnect power when hazardous gasses are present.
Disconnect the power cable before removing any enclosure panel.
UNPACKING
Remove all the equipment from the packaging, and store the packaging in a safe place. File any damage
claims with the carrier.

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CLEANING
Clean only with a damp cloth.

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DIN RAIL MOUNTING
Install the unit on a standard 35mm Din-Rail. Recess the unit to allow at least 3” of horizontal clearance for
copper cable bend radius. Recess the unit to allow at least 5” of horizontal clearance for fiber cable bend
radius. There should be at least 3” of clearance on both the top and bottom of the unit to allow proper
ventilation.
To install the unit to 35mm industrial DIN rail,
place the top edge of the included mounting
bracket on the back of the unit against the DIN rail
at a 15° angle as shown. Rotate the bottom of the
unit to the back (away from you) until it snaps into
place.
To remove the unit from the 35mm industrial
DIN rail, pull forward on the unit until it disengages
from the bottom of the DIN rail. Rotate the bottom
of the unit towards you and up at an approximate
15° upward angle to completely remove the unit.
URMK CPMA-2
Most N-Tron™ products are designed to be mounted on industry standard 35mm DIN rail. However, DIN
rail mounting may not be suitable for all applications. Our Optional Universal Rack Mount Kit (P/N:
URMK) may be used to mount the enclosure to standard 19" racks, and our Optional Factory Installed Panel
Mount Assembly (P/N: CPMA-2) may be used to mount the enclosure to a panel or any other flat surface.

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FRONT PANEL (712FX4)
From Top to Left:
RJ45 Ports Auto Sensing 10/100 Base-TX Connections
Fiber Ports 100 Base-FX Connections
LED lights when Power is supplied to the unit
NOTE: The RJ45 data port has two LEDs located on each connector. The left LED indicates LINK status,
and the right LED indicates ACTIVITY.
LEDs: The table below describes the operating modes:
LED Color Description
GREEN Power is ON
RED Power is ON and a fault condition exists
OFF Power is OFF
LNK GREEN 10/100Mb Link between ports
OFF No Link between ports
ACT GREEN Data is active between ports
OFF Data is inactive between ports

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APPLYING POWER (Top View)
•Unscrew & Remove the DC Voltage Input
Plug from the Power Input Header
•Install the DC Power Cables into the Plug
(observing polarity).
•Plug the Voltage Input Plug back into the
Power Input Header.
•Tightening torque for the terminal block
power plug is 0.5 Nm/0.368 Pound Foot.
•Verify the Power LED stays ON (GREEN).
Notes:
•Only 1 power supply must be connected to power for minimal operation. For redundant power
operation, V
1
and V
2
inputs must be connected to separate DC Voltage sources. This device will
draw current from both sources simultaneously. Use 16-28 gauge wire when connecting to the
power supply.
•The Fault pins on the power connector can be used for an alarm contact. The current carrying
capacity is 1A at 24VDC. It is normally open and the relay closes when a fault condition occurs.
These pins can be used to connect an external warning device such as a light in order to provide an
external alarm. The conditions for generating a fault condition (closing the relay) can be configured
through software.
Recommended 24V DC Power Supplies, similar to: N-Tron’s P/N NTPS-24-1.3 (NOTE: Not appropriate
for use with M12, POE, and HV models.):
•
Input AC 115/230V
•Output DC 24-28V
•Output Current 1.3A @ 24V
1.0A @ 28V
•
Power 30W
•35 mm DIN-Rail Mountable
•Dimensions: 45X75X91 mm

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Connecting the Unit
For FX/FXE units, remove the dust cap from the fiber optic connectors and connect the fiber optic cables.
The TX port (located on the bottom connector) on the FX/FXE models should be connected to the RX port of the
far end station. The RX port (located on the top connector) on the FX/FXE versions should be connected to the
TX port of the far end station.
For 10/100 Base-TX ports, plug a Category 5E twisted pair cable into the RJ45 connector. Connect the
other end to the far end station. Verify that the LNK LEDs are ON once the connection has been completed.
To connect any port to another device (end node, Switch or Repeater), use a standard Category 5E straight
through or crossover cable with a
minimum length of one meter and a
maximum length of 100 meters.
N-Tron recommends the use of pre-
manufactured Cat5E cables to ensure the
best performance. If this is not an option
and users must terminate their own ends
on the Cat5E cables; one of the two color
coded standards shown to the right should
be utilized. If a user does not follow one
of these two color code standards then the
performance and maximum cable distance
will be reduced significantly, and may
prevent the switch from establishing a
link.
Warning: Creating a port to port connection on the same switch (i.e. loop) is an illegal operation and
will create a broadcast storm which will crash the network!

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N-TRON SWITCH GROUNDING TECHNIQUES
The grounding philosophy of any control system is an integral part of the design. N-Tron switches are
designed to be grounded, but the user has been given the flexibility to float the switch when required. The
best noise immunity and emissions (i.e. CE) are obtained when the N-Tron switch chassis is connected to
earth ground via a drain wire. Some N-Tron switches have metal din-rail brackets that can ground the
switch if the din-rail is grounded. In some cases, N-Tron switches with metal brackets can be supplied with
optional plastic brackets if isolation is required.
Both V- legs of the power input connector are connected to chassis
internally on the PCB. Connecting a drain wire (shown in green) to
earth ground from one of the V- terminal plugs as shown here will
ground the switch and the chassis. The power leads from the power
source should be limited to 3 meters or less in length.
As an alternate, users can run a drain wire (shown in green) & lug from any of the Din-
Rail screws or empty PEM nuts on the enclosure. When using an unused PEM nut to
connect a ground lug via a machine screw, care should be taken to limit the penetration
of the outer skin by less than 1/4 in. Failure to do so may cause irreversible damage to
the internal components of the switch.
Note: Before applying power to the grounded switch, you must use a volt meter to verify
there is no voltage difference between the power supply’s negative output terminal and
the switch chassis grounding point.
If the use of shielded cables is required, it is generally recommended to only connect the shield at one end to
prevent ground loops and interfere with low level signals (i.e. thermocouples, RTD, etc.). Cat5e cables
manufactured to EIA-568A or 568B specifications are required for use with N-Tron Switches.
In the event all Cat5e patch cable distances are small (i.e. All Ethernet devices are located in the same local
cabinet and/or referenced to the same earth ground), it is permissible to use fully shielded cables terminated
to chassis ground at both ends in systems void of low level analog signals.

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RJ45 CONNECTOR CRIMP SPECIFICATIONS
Please reference the illustration below for your Cat5 cable specifications:

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USB INTERFACE
The 712FX4 Series switches provide a USB interface accessed via the USB connector labeled as “USB” on
the unit. This is used to access the Command Line Interpreter (CLI).
The USB connector is at the bottom of the 712FX4.
USB Cable
Connect the USB port of your PC and the Switch using a standard USB cable. You will require a cable with
a Type A connector for the PC end, and a Type B connector for the Switch end.
Standard USB cables are readily available from a variety of computer stores.
HyperTerminal
The following configuration should be used in HyperTerminal:
Port Settings: 115200
Data Bits: 8
Parity: NONE
Stop bits: 1
Flow Control: NONE

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Overview of Advanced Features
Mode of Operation
Each port on the switch can be configured into different modes of operation as shown below:
Copper Ports: 100Base Fiber Ports: 1000Base Copper/Fiber Ports:
- Half Duplex - Full Duplex - Full Duplex
- Full Duplex
- Auto Negotiation
Half Duplex
In half duplex mode, the CSMA/CD media access method is the means by which two or more stations share
a common transmission medium. To transmit, a station waits (defers) for a quiet period on the medium (that
is, no other station is transmitting) and then sends the intended message in bit-serial form. If, after initiating
a transmission, the message collides with that of another station, then each transmitting station intentionally
transmits for an additional predefined period to ensure propagation of the collision throughout the system.
The station remains silent for a random amount of time (back-off) before attempting to transmit again.
Full Duplex
Full duplex operation allows simultaneous communication between a pair of stations using point-to-point
media (dedicated channel). Full duplex operation does not require that transmitters defer, nor do they
monitor or react to receive activity, as there is no contention for a shared medium in this mode.
Auto Negotiation
In Auto Negotiation mode, the port / hardware detects the mode of operation of the station that is connected
to this port and sets its mode to match the mode of the station.
Port Mirroring
A Mirroring Port is a dedicated port that is configured to receive the copies of Ethernet frames that are being
transmitted out and also being received in from any other port that is being monitored.
Port Trunking
Port Trunking is the ability to group two network ports to increase the bandwidth between two machines
(switch or any work station). This feature allows grouping of high-speed connectivity and provides
redundant connection between switches, so that a trunk can act as a single link between the switches.
Quality of Service (QoS)
Quality of service (QoS) refers to resource reservation control mechanisms. Quality of service is the ability
to provide different priority to different applications, users, or data flows. Quality of service guarantees are
important if the network capacity is insufficient, especially for real-time streaming multimedia applications
such as voice over IP, online games and IP-TV, since these often require fixed bit rate and are delay
sensitive, and in networks where the capacity is a limited resource, for example in cellular data
communication. In the absence of network congestion, QoS mechanisms are not required.

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Each of these three QOS methods below is included or not based on the settings on the relevant browser
page:
1) Force High Priority (Port Based),
2) IEEE802.1p (Tagged QOS), or
3) DSCP (differentiated services code points) (RFC 2474).
When Force High Priority is enabled, the port based priority is included in the decision for all ports and all
frames received on a port will use the default QOS priority for that port in the decision. For example, if it is
desired to have ingress frames on a port egress to the highest priority transmit queue regardless of other
factors, then enable Force High Priority and set the port's Default Port Priority to 7.
Virtual LAN
The switch provides support for setting up tagged Virtual LANs (Local Area Networks). A port may belong
to any number of Virtual LANs. The VLAN membership of a device is determined by the VLAN(s) that
have been defined for the port to which the device is connected. If a device should move from one port to
another, it loses its current VLAN membership and inherits that of the new port it is connected to.
VLANs facilitate easy administration of logical groups of devices that can communicate as if they
were on the same LAN. Traffic between VLANs is restricted, unless the ports are explicitly configured
as overlapping VLANs. Switches forward unicast, multicast, and broadcast traffic only on LAN segments
that serve the VLAN to which the traffic belongs.
A Default Virtual LAN (VID=1) exists to which a port, which is not a member of any other Virtual LAN,
will belong. This allows the switch to operate as a ‘normal’ switch when it is used in a network. A port is
automatically removed from the Default VLAN when it is reconfigured to belong to another Virtual LAN,
because that is the most common operation. But, if desired, the port can be included in VLAN 1 by
configuring VLAN 1 last.
If switch ports are configured to transmit and receive untagged frames, end devices are able to communicate
throughout the LAN. Using Tagged VLANs, the switch has the ability to take non-tagged packets in some
ports, add a VLAN tag to the packet and send it out tagged ports on the switch. The VLANs can also be
configured to accept tagged packets in tagged ports, strip the tags off the packets, and send the packets back
out other untagged ports. This allows a network administrator to set up the switch to support devices on the
network that do not support VLAN Tagged packets. The administrator can also set up the ports to discard
any packets that are tagged or to discard any packets that are untagged based on a hybrid VLAN of both
tagged and untagged ports, and using the VLAN Ingress Filter on the switch.
For each switch port there is one and only one PVID (port VLAN ID) setting. If an incoming frame is
untagged and untagged frames are being accepted, then that frame will inherit the tag of the PVID value for
that port. Subsequent switch routing and treatment will be in accordance with that VLAN switch map. By
configuring PVIDs properly and configuring for all frames to exit untagged, the switch can achieve a ‘port
VLAN’ configuration in which all frames in and out can be untagged, thus not requiring external devices to
be VLAN cognizant.
To understand how a VLAN configuration will perform, first look at the port on which the frame enters the
switch, then the VLAN ID (if the frame is tagged) or the PVID (if the frame is untagged). The VLAN
defined by the VID or PVID defines a VLAN group with a membership of ports. This membership
determines whether a port is included or excluded as to frame egress from the switch.