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IGMP version 1 is formally described in the Internet Engineering Task Force (IETF) Request for Comments
(RFC) 1112. The 700 Series supports v1 and v2.
N-Ring
N-Ring is enabled by default, and the switch is Plug and Play for N-Ring except that initially one must
enable an N-Ring enabled device to be the N-Ring Manager for a given N-Ring. Subsequently, N-Ring
operates dynamically upon each power up. Using N-Tron's proprietary N-Ring technology offers expanded
ring size capacity, detailed fault diagnostics, and a standard healing time of 30ms. The N-Ring Manager
periodically checks the health of the N-Ring via health check packets. If the N-Ring Manager stops
receiving the health check packets, it times out and converts the N-Ring to a backbone within 30ms. When
using all N-Ring enabled switches in the ring, a detailed ring map and fault location chart is also provided
on the N-Ring Manager‘s web browser. N-Ring status is also sent from the N-Ring Manager to the N-View
OPC Server to identify the health status of the ring. Up to 250 N-Ring enabled switches can participate in
one N-Ring topology. Switches that do not have N-Ring capability may be used in an N-Ring, however the
ring map and fault location chart cannot be as detailed at these locations.
N-Link
The purpose of N-Link is to provide a way to redundantly couple an N-Ring topology to one or more other
topologies, usually other N-Ring topologies. Each N-Link configuration requires 4 switches: N-Link
Master, N-Link Slave, N-Link Primary Coupler, and N-Link Standby Coupler. N-Link will monitor the link
status of the Primary and Standby Coupler links. While the Primary Coupler link is healthy, it will forward
network traffic and the Standby Coupler link will block network traffic. When a problem is detected on the
Primary Coupler link, the Primary Coupler link will block network traffic and the Standby Coupler link will
forward network traffic. While the N-Link Master and Slave are in communication via the Control link,
only one Coupler link (Primary or Standby) will forward network traffic while the other Coupler link will
block network traffic.
CIP
The CIP (Common Industrial Protocol) feature allows N-Tron switches to directly provide switch
information and configuration access to Programmable Logic Controller (PLC) and Human Machine
Interface (HMI) applications via a standardized communication protocol. For example, a PLC may be
programmed to monitor port links or N-Ring status and cause a status indicator to turn red on an HMI if a
port goes link down or if N-Ring has a fault. CIP is formally described in ODVA Publication Number
PUB00001 (Volume 1: Common Industrial Protocol (CIP™)), and Publication Number: PUB00002
(Volume 2: EtherNet/IP Adaptation of CIP). N-Tron provides EDS and ICO files. N-TRON_CIP_Tags.pdf
is for a particular environment, but reveals the tags available.
DHCP
The Dynamic Host Configuration Protocol (DHCP) provides configuration parameters to Internet hosts.
DHCP is built on a client-server model, where designated DHCP server hosts allocate network addresses
and deliver configuration parameters to dynamically configured hosts. DHCP is controlled by RFC 2131.
The N-Tron DHCP Switch can be configured to be a DHCP Client. Alternately the N-Tron DHCP switch
can be configured to be a DHCP Server, a DHCP Relay Agent, or both.
For more detailed information on N-Tron DHCP features, reference: http://www.n-tron.com/tech_docs.php.
Under ‗White papers‘, see. ―Using DHCP to Minimize Equipment Setup Time‖. Under ‗Installation Guides
and User Manuals‘ see ―DHCP Technical Instructions for 708 / 716/ 7018 / 7506 Series‖.