PROFINET – Network Infrastructure
PROFINETNetwork Infrastructure
• Office vs. Industrial Network• Topologies• Installation• Cabling and Components
Network Infrastructure
NetworkInstallation
Office
Differences betweenOffice and Industrial networks
Location Air-conditioned offices Rough environment
Installation Network specialists Plant commissioning personnel
Topology Tree / Star Plant-specific
Availability Second to minute range accepted
Network downtimes < 300 ms
Device density High, switches with a large number of ports
Low, switcheswith few ports
Network monitoring By specially-trained personnel
Part of plant monitoring
Industry
Ethernet networks in the office
• Tree structured network topologies following ISO/IEC 11801 with application independent cabling systems
FD
FD
BD
Building 2Building 1
BD = Building Distributor, FD = Floor Distributor
BD
FD
FD
Twisted Pair
• 10BaseT - 10Mbps base band twisted pair system– Category 5 Unshielded twisted pair– Maximum 100m – RJ-45 Connector – Star topology
Fiber Optic
• 10BaseF – 10Mbps Base band Fiber Optic system– Requires 2 strands of Fiber cable– Maximum 2000m (except for 10BaseFP-
500m)– ST Connectors– Singlemode vs. multimode
Half-duplex mode– Transmission of data in only one direction
at a time– i.e. walkie-talkie
1
Half and Full-Duplex Explained
PC
Transmit
Receive
PC
TX+
RX+
RX-
Transmit
Receive
TX+
TX-
RX+
RX-
TX- 1001 010
Half and Full-Duplex Explained
Transmit
Receive
Transmit
Receive
Switch PC
TX+RX+
RX-
TX+
TX-
RX+
RX-
Transmit
Receive
PC
TX+
TX-
RX+
RX-
RX+
RX-
TX+
TX-
TX-0 101
Full-duplex mode– Transmission of data in two directions
simultaneously– i.e. telephone– Full-duplex is a requirement for PROFINET IO
10 01
• 100Base-TX - 100Mbps base band twisted pair system– Cat 5 UTP or Type 1 STP cabling– Maximum 100m
• 100Base-T4– Uses 4 pairs of Cat 3, 4, or 5 UTP
• 100Base-FX – 100Mbps Fiber Optic system– Requires 2 strands of Fiber cable– SC Connectors
Fast Ethernet
Gigabit Ethernet
• 1000Base-T - 1000Mbps base band twisted pair system– Uses 4 pairs of Cat 5 UTP or Cat 6– RJ-45 Connector
• 1000Base-X – Identifier for 3 media types– 1000Base-SX (Short wavelength)– 1000Base-LX (Long wavelength)– 1000Base-CX (short copper jumper)– SC and MT-RJ connectors
Location Air-conditioned offices Rough environment
Installation Network specialists Plant commissioning personnel
Topology Tree / Star Plant-specific
Availability Second to minute range accepted
Network downtimes < 300 ms
Device density High, switches with a large number of ports
Low, switcheswith few ports
Network monitoring By specially-trained personnel
Part of plant monitoring
IndustryOffice
Differences betweenOffice and Industrial networks
Ethernet networks in Industrial environment
BD BD
MD MD
FD
FD
Machine 1 Machine 2
Floor 1
Floor 2
BuildingOffice
BuildingProduction
FloorDistributor
BuildingDistributor
CampusDistributor CD
• fixed basic installation -variable device connections
• Star and tree structures
• Individual networking degree for any machine / plant
• Star, ring and line structures
MachineDistributor
CD
Industrial Environment Factors to consider
Office Area Production and Field Areas
Moderate Temperatures Extreme temperatures
Low Dust burden High dust burden
No moisture Moisture possible
Virtually no vibrations Vibrating Machines
Low EMC burden High EMC burden
Low mechanical danger Danger of mechanical damage
Low UV radiation UV burden in outer area
Virtually no chemical danger Chemical burden from oily or aggressive atmospheres
BUS
Network Topologies
STAR
TREE
RING
PROFINET networksTree and Star topology
• PROFINET supports both tree and star topologies • Easy Administration of the network• Flexible addition / removal of stations• Favorable network component cost per port
through high port density
PROFINET networksRing Topology
• PROFINET supports the ring topology for high availability (redundancy)
– For example, if a cable or device fails, then the system will automatically segment itself to a ‘line’ topology keeping the rest of the system active
PROFINET networksLine Topology
• PROFINET supports the line topology for minimal cabling overhead
• Embedded Switches in the devices (external switches optional)
• Allows topologies like classic fieldbus systems
Contents of the PROFINET Installation Guide
• Network components
• Network structures
• Installation Wiring
– Plugs
– Cables
• Installation hintsPROFINET Installation Guide Part 1 & 2
Installation & Wiring -Copper
• Transmission as defined in IEC 8802-3 (100 BASE-TX)• Conducting wires
– Twisted Pair as defined in IEC 11801, CAT5e (Details IEC 61156)
– Hybrid version with Power & Signal• Connectors IP20
– RJ45 from office application– Useful for industrial application
(connectable to AWG22)– Can be assembled in the field
• Connector IP65 (outside of cabinet)– Compatible to IP20 variant– Can be assembled in the field– Hybrid variant with Power & Signal– M12 plug connector (with 4 poles)
Fiber Optic Components
• Immunity to EMI/RFI and lightning damage
• No ground loops • Low attenuation (data loss) • Longer distance
- 2 km with Multimode fiber - >10 km with Single Mode
fiber • Small and lightweight cable • No shock hazard • Longer life expectancy than
copper or coaxial cable
CoreCladding
Buffer Coating
Core – Thin glass fiber where light travelsCladding – Optical material surrounding the core that reflects light back into the coreBuffer Coating – Outer coating that protects the fiber from damage
Installation & Wiring -Fiber Optics (FO)
• Connectors IP20– Type SC-Duplex (Push/Pull Connector)– Type BFOC/2,5 (Bayonet Connector)– Can be assembled in the field
• Transmission as defined in IEC 8802-3 (100 BASE-FX)• Conducting wires
– Glass fiber optic ISO/IEC 60793, 60794– Multi-mode fiber: max. 2 km
Mono-mode fiber: max. 14 km
• Connector IP65 (outside of cabinet)– Simplex connector– Can be assembled in the field– Hybrid variant with Power & Signal
Network Components
• There are many types of Connectivity devices
• They all help to manage traffic on a network
• Some of theses devices are…– Hubs– Switches– Routers
Hub
Hubs
• Allows a network to function as if it where connected by a single line
• Receives and retransmits signals to all ports• Results in higher network load / not
recommended in field level installations
Switches
• Associates each port with physical addresses connected through it
• Sends frame out the port associated with the physical address
• Improves the performance of the network
• Two most common types…– Cut-through– Store and forward
Switch
Switch Operation
A
B
D
C
Switch
A to CB to D
Simultaneously
47-2C-36-64-00-00
55-E0-08-33-4E-39
91-09-83-5B-03-09
14-45-08-7A-11-16
Switch
Learning MAC Addresses
Port 2Port 3
Port 1
Port 4Node A
Node B Node D
Node C!
Node B MAC
1234.
Lookup tableAddress PortNode A
???.
Node ANode B
??.
Which Switch to use for PROFINET?
Feature Description Used in PROFINET?
Managed vs. Unmanaged Managed switches offer advanced features Both can be
usedQuality of Service (QOS) Prioritize frames according IEEE 802.1p/q recommended
Trunking Increase bandwidth Useful
VLAN Isolates traffic of different network sections Useful
Port Mirroring Helps to monitor traffic of a device Useful
IGMP Snooping Reduces Broadcast traffic Not needed
• Managed switches are plug and play but also support SNMP and other advanced features such as Web access, Telnet, for improved diagnostics, commissioning and configuration (redundancy for example)
• Unmanaged switches are also plug and play and usually without many additional features. What you see is what you get! (WYSIWYG)
Managed vs. Unmanaged
Switch
Switch
Switch
• Without QOS the switch will forward data in the order it receives… first in, first out (Standard Store and Forward)
• With QOS the switch will forward based on a priority field in the Ethernet frame (highest priority frame is then sent first)
Quality of Service (QOS)
• IEEE 802.1p enables traffic priority (QOS) on layer 2 switches
HIGH Priority Message!
B Sender
A Sender C Sender
D Receiver
VLANs (Virtual LANs)
SwitchBuilding 1 Floor 2
Building 2 Floor 1
Switch
Switch
Engineering VLAN Accounting VLANMarketing VLAN
Building 1 Floor 1
• VLANs logically segment the network • VLANs improve the performance of the network because
broadcast traffic is kept local
VLANs cont’
• Main Advantages of VLANs– Can divide the network into ‘switched’ separate
broadcast domains for increased performance without the use of routers
• (routers are more complex to manage and add more overhead since they operate at layer 3 of the OSI model)
– Ease of configuration– Ease of device movement without changes to the
device– Lower cost per port (routers are more expensive
than switches)
Port Mirroring
Switch Switch
Mirror Port
• Defining a mirror port duplicates all traffic on the mirror– in- and outgoing traffic
• Useful for monitoring traffic on a certain port– e.g. with Ethereal
• Available in managed switches or as dedicated device• Useful to trace network traffic for diagnostic reasons
Monitor Port
Trunking (Link Aggregation)
Switch Switch
Switch Switch
Trunking helps eliminate bottlenecks
Without trunking• One packet after the other will be sent
With trunking• Doubles the bandwidth between 2 switches
Port Trunking spreads traffic between switches on multiple connections
Wireless Ethernet
• Wireless Ethernet according to IEEE 802.11• Features available for Industrial Wireless
applications• Advantages
– Cost savings through reduction in cabling and installation– No wear on rotating and moving devices (ex. Slip ring, drag chains)– Mobile diagnostics, monitoring, and operation– Moving machines, monorail systems
Wireless Ethernet (IEEE 802.11)
IEEE 802.11b IEEE 802.11g IEEE 802.11a
Approx Range 100m* Approx Range 100m* Approx Range 100m*
No clients 8 Max No clients 8 No Clients 35
Limited data rate with 11Mbit/s
High data rate with 54 Mbit/s
High data rate with 54Mbit/s
3 separate channels 3 separate channels 8 separate channels
For indoor / outdoor For indoor / outdoor Only permitted indoor
Transmission power 100mW
Transmission Power 100mW
Transmission Power 20mW
Compatible with IEEE 802.11b radio networks
Not Compatible with IEEE 802.11 b/g
Frequency 2.4 GHz Frequency 2.4 GHz Frequency 5 GHz
*Actual range may vary based upon environmental conditions
Which Wireless to use for PROFINET?
Feature Description Used in PROFINET?
Wireless Link Monitoring
The access point continuously checks the status of the wireless link for errors.
Useful for diagnostics
Bandwidth reservation
Reserve a portion of the bandwidth for important IO Traffic
Recommended in IO applications
Antenna Diversity Use multiple Antenna’s on the Wireless Access point (2.4 & 5 Ghz) for better reception
Useful in difficult radio signal areas
Redundancy Reliable Wireless infrastructure by coupling multiple Access points for a redundant link
Useful for higher availability
Rapid roaming A rapid way of roaming between Wireless Cells when times in the range of 10 -> 100 ms are required Useful
R-Coax Allows specific radio fields to be formed for controlled reception of Wireless LAN Cells Useful
Routing
• MAC address– Local address (LAN traffic)– based on hardware and
manufacturer• IP address
– can be used for WAN traffic
– User defined • Routers are the bridge
between local networks Physical
Data Link
Network
Transport
Session
Presentation
Application
Hubs
Switches
Routers
Connecting Networks
212.18.23212.18.23.88.88
212.18.23212.18.23.7.7
212.18.23212.18.23.12.12 119119.88.26.6.88.26.6
119119.88.26.58.88.26.58
119119.88.26.79.88.26.79
183.202183.202.67.25.67.25
183.202183.202.67.8.67.8
183.202183.202.67.84.67.84
Network CNetwork C
Factory Factory ArizonaArizona
Network BNetwork B
Factory Factory TennesseeTennessee
Router (Gateway) Router (Gateway) between the between the
networksnetworks
Network ANetwork A
Corp.Corp.
Washington, DCWashington, DC
Net ID Host ID
Parts of the IP Address
Subnet Mask
31
11111111 11111111 11111111 00000000
Subnet IDNet ID Host ID
0 IP Address
The Subnet Mask distinguishes the local network from the remote
Max 256 Host IDsMax 256 SubnetsSubnet Mask
2551 1 1 1 1 1 1 1
.2551 1 1 1 1 1 1 1
.2551 1 1 1 1 1 1 1
.00 0 0 0 0 0 0 0
.1401 0 0 0 1 1 0 0
.320 0 1 0 0 0 0 0
1421 0 0 0 1 1 1 0
.1281 0 0 0 0 0 0 0
Net ID Host ID
Subnet Mask Example
SM: 255.255.255.0
Host ID: 140
Class B: IP: 142.128.32.140 / 24 bits
Subnet ID: 32
PROFINET and Routing
• Design your network carefully– To get the maximum performance
real-time traffic should stay local (LAN)• No routers between field devices and
controllers– Don’t send cyclic I/O data over routers– Pack data before sending over routers – Use TCP/IP based traffic for sending data
over WAN (e.g. OPC, PROFINET CBA)
PROFINET Network Infrastructure Summary
• Ethernet as defined in IEEE 802.3• Commercial-Off-The-Shelf (COTS)• Fast Ethernet (100 MBit/s) as defined in 100 BASE-TX• Gigabit Ethernet for network backbone• Full Duplex operation• Support of all network topologies to fit the needs of the
application• Auto-Cross-Over function
– Exchange of conducting wires is repaired automatically by the Auto-Cross-Over function of the network components
Engineering
Controller
Switch
I/O
PROFIBUS
Wireless
I/O
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PROFINET
I/O
I/OPROFIBUS
PB Slave
Proxy
Proxy
230.2226.2
Modbus
Controller
Proxy
PROFIBUS
HMI
XX55
CE
Direct06
DeviceNet
Proxy
Network Infrastructure Demo
WSerial
Proxy