Modbus Tcp - RuggedCom RuggedServer RS910 Specifications

Serial IP Encapsulation
Many 'legacy' devices (RTU, PLC, IED, etc.) only support
serial communications via RS232, RS422 or RS485. ROS
encapsulates the serial data within a TCP connection
allowing these devices to be reached via an IP network.
A wide range of baud rates, frame packetization options,
and diagnostics allows any serial protocol to function. The
RS910 has specific support for the following serial protocols:
Raw Socket serial encapsulation
„ „
Modbus TCP (client and server)
„ „
„ „ DNP 3
WIN and TIN
„ „
Microlok
„ „

MODBUS TCP

The Modbus protocol is ubiquitous in the industrial control
and automation world. ROS
slave serial data packets to Modbus TCP client/server
packets for transmission over an IP network. This allows
communications to Modbus RTU slaves via Ethernet and
allows multiple masters to poll the same slave device.
Cyber Security
Cyber security is an urgent issue in many industries where
advanced automation and communications networks play a
crucial role in mission critical applications and where high
reliability is of paramount importance. Key ROS
that address security issues at the local area network level
include:
Passwords - Multi-level user passwords secures switch
„ „
against unauthorized configuration
SSH / SSL - Extends capability of password protection to
„ „
add encryption of passwords and data as they cross the
network
Enable / Disable Ports - Capability to disable ports so
„ „
that traffic can not pass
802.1Q VLAN - Provides the ability to logically segregate
„ „
traffic between predefined ports on switches
„ „ MAC Based Port Security - The ability to secure ports
on a switch so only specific Devices / MAC addresses
can communicate via that port
802.1x Port Based Network Access Control - The
„ „
ability to lock down ports on a switch so that only
authorized clients can communicate via this port
RADIUS - Provides centralized password management
„ „
SNMPv3 - encrypted authentication and access security
„ „
The ROS cyber security features are included to
®
helpaddress the various industry specific security standards
such as NERC CIP, ISA S99, AGA 12, IEC 62443, ISO
17799:2005 and PCSRF SPP-ICS.
Enhanced Rapid Spanning Tree Protocol (eRSTP™)
RuggedCom eRSTP™ allows the creation of fault-tolerant
ring and mesh Ethernet networks that incorporate redundant
links that are 'pruned' to prevent loops. eRSTP™ yields
www.RuggedCom.com
2-Port Serial Device Server with up to 3 Ports Managed Ethernet Switch
converts Modbus RTU master/
®
features
®
RuggedServer™ RS910
ROS
worst-case fault recovery1 of 5ms times the
'bridge diameter' and allows rings of up to 160
switches. For example, a ring of ten switches will have fault
®
recovery times under 50ms. eRSTP™ implements both
STP and RSTP to ensure interoperability with commercial
switches unlike other proprietary 'ring' solutions.
Quality of Service (IEEE 802.1p)
Some networking applications such as real-time control
or VoIP (voice over IP) require predictable arrival times for
Ethernet frames. Switches can introduce latency in times of
heavy network traffic due to the internal queues that buffer
frames and then transmit on a first come first serve basis.
ROS supports 'Class of Service' in accordance with IEEE
®
802.1p that allows time critical traffic to jump ahead to the
front of the queue thus minimizing latency and reducing jitter
to allow such demanding applications to operate correctly.
ROS allows priority classification by port, tags, MAC
®
address, and IP type of service (ToS).
A configurable "weighted fair queuing" algorithm controls
how frames are emptied from the queues.
VLAN (IEEE 802.1Q)
Virtual local area networks (VLAN) allow the segregation
of a physical network into separate logical networks with
independent broadcast domains. A measure of security is
provided since hosts can only access other hosts on the
same VLAN and traffic storms are isolated. ROS
802.1Q tagged Ethernet frames and VLAN trunks. Port
based classification allows legacy devices to be assigned to
the correct VLAN. GVRP support is also provided to simplify
the configuration of the switches on the VLAN.
Link Aggregation (802.3ad)
The link aggregation feature provides the ability to
aggregate several Ethernet ports into one logical link (port
trunk) with higher bandwidth. This provides an inexpensive
way to set up a high speed backbone to improve network
bandwidth. This feature is also known as "port trunking",
"port bundling", "port teaming", and "Ethernet trunk".
IGMP Snooping
ROS uses IGMP snooping (Internet Group Management
®
Protocol v1&v2) to intelligently forward or filter multicast
traffic streams (e.g. MPEG video) to or from hosts on the
network. This reduces the load on network trunks and
prevents packets from being received on hosts that are
not involved. ROS has a very powerful implementation of
®
IGMP snooping that:
1 eRSTP fault recovery times may be approximated as follows:
For 100 Mbps, fault recovery performance is <5ms/hop
For 1,000 Mbps, fault recovery performance is <5ms/hop + 20ms
Features
®
RuggedServer™ RS910
supports
®
3