• Increase of the network performance;
  by filtering the data traffic on the basis of the Ethernet (MAC) address of the data terminals, data traffic remains local; only data intended for users of another subnetwork is forwarded by the switch.
• Simple network configuration and network expansion;
  the switch saves the data received at the ports and forwards it automatically to the destination address. Collision detection (CSMA/CD method) does not restrict the expansion of the network beyond the port.
• Limitation of the error propagation to the affected subnetwork;
  the SCALANCE X-300 switches only forward data with a valid checksum (CRC).
• Integration of existing subnetworks with 10 Mbps into Fast Ethernet networks with 100 Mbps;
  at the twisted-pair ports, the SCALANCE X-300 switch automatically recognizes the conductor pairs for transmission and reception (Autocrossover), the data transfer rate of 10 or 100 or 1000 Mbps, as well as full-duplex and half-duplex mode (Autonegotiation).
• High-performance connection of SCALANCE X-300 switches with 1 Gbps;
  SCALANCE X-300 switches have Gigabit Ethernet ports for connecting the switches to each other or with other Gigabit-Ethernet-enabled components (e.g. SCALANCE X-400, X-500)
• Integrated redundancy manager for constructing Fast Ethernet and Gigabit Ethernet ring topologies with high-speed media redundancy.
• High-speed standby redundancy;
  several network segments such as rings can be interconnected redundantly with SCALANCE X-300 by means of the integrated standby function. Two X-300 switches are configured in a ring as a master and slave and are connected via two links to the other ring. The redundant connection can be made at 1000 Mbps.
• Redundant interfacing to higher-level networks;
  SCALANCE X-300 switches support the standardized redundancy procedures Spanning Tree Protocol (STP) and Rapid Spanning Tree Protocol (RSTP). This enables a subnetwork to be connected redundantly to a higher-level network with reduced requirements for the reconfiguration time (in the order of seconds). By supporting the Multiple Spanning Tree Protocol (MSTP), a network can also be split into multiple sub-segments.
• Support of virtual networks (VLAN);
  for structuring Industrial Ethernet networks with a fast growing number of users, a physically existing network can be divided into several virtual networks.
• Load limiting when multicast protocols (e.g. video transmission) are used;
  through learning the multicast sources and targets (IGMP Snooping, IGMP Querier), SCALANCE X-300 switches can also filter multicast data traffic and therefore limit the load in the network.
• Configuration of the ports for terminals that support authentication in accordance with IEEE 802.1x. Authentication is by means of a RADIUS server that must be configured appropriately and must be accessible via the network.
• Support of the DHCP Option 82, 66, 67 (Dynamic Host Configuration Protocol);
  this permits the IP address assignment of a terminal depending on the connected Switch Port. The IP address assignment is by means of a DHCP server that must be configured appropriately and must be accessible via the network.
• Support from the Access Control List (ACL);
  if this function is activated for one port, the switch forwards the message frames received to this port if its source address is present in the address table. All connected nodes can be automatically entered in the ACL.
• Syslog;
  Syslog compliant with RFC 3164 is used in the IP network for transmitting short, unencrypted text messages via UDP. This requires the use of a Syslog server that must be configured appropriately and must be accessible via the network.
• Time synchronization;
  diagnostic messages (log table entries, e-mails) are time-stamped. The local time is standardized throughout the network by means of synchronization with a SICLOCK time transmitter, SNTP or NTP server or via IEEE1588, thereby simplifying the assignment of diagnostic messages of several devices.
• Fast replacement of devices in event of failure, by means of the C-PLUG switching medium

Network topology and network configuration

The SCALANCE X-300 Industrial Ethernet switches with degree of protection IP30 are typically accommodated in a control cabinet along with the nodes to be connected. Electrical and optical versions can be installed together in star, line and ring topologies.

The following network structures and combinations of structures can be implemented:

• Fast Ethernet and Gigabit Ethernet rings with fast media redundancy;
  to increase network availability, as many as 50 X-200, X-300, X-400 or X-500 switches can be cascaded in line can be connected into a ring
• Several rings can be redundantly linked through the standby function
• At the same time, SCALANCE X-300 supports redundant connection of the ring structure to the corporate network with Rapid Spanning Tree.
• Star topology with SCALANCE X-300 switches:
  The SCALANCE X-300 switch represents a star point which can interconnect several nodes or subnets electrically or optically.

When configuring the network, it is necessary to observe the following boundary conditions:

• Maximum line length between two modules for multi-mode fiber-optic conductors:
  • 750 m at 1 Gbps
  • 5 km at 100 Mbps
• Maximum line length between two modules for single-mode fiber-optic conductors:
  • 10 to 70 km at 1 Gbps
  • 26 km at 100 Mbps
• Maximum cable length of the TP cable between two SCALANCE X switches:
  • Max. 100 m with IE FC cable 2x2 and IE FC RJ45 Plug 180
  • Max. 100 m at 1 Gbps with IE FC Standard Cable 4x2 (90 m), IE FC RJ45 Modular Outlet and patch cable (10 m)
  • Max. 10 m using patches with TP Cord

Commissioning and diagnostics

Setting options on the device itself:

• Redundancy manager RM;
  to establish a ring, a SCALANCE X-300 is switched to RM mode. The Gigabit ports (electrical or optical) are preferably used as ring ports.
• Signal mask;
  the signal mask is set to the current status of the SCALANCE X-300 (setpoint) by pushbutton operation. The signal mask defines which ports and which power supplies are to be monitored. The signaling contact only reports an error when a monitored port or a monitored feeder fails (deviation of setpoint/actual status).
• IP address;
  the IP address is assigned via DHCP (Dynamic Host Configuration Protocol). If there is no corresponding server in the network, the IP address can be assigned using an enclosed software tool.

Diagnostic options on site:

• The following status information is displayed by LEDs on site:
  • Port status
  • Port mode (10/100/1000 Mbps, full/half-duplex)
  • Status of the two power supplies
  • Signaling contact status
  • Signal mask (setpoint status)
  • RM mode
  • Standby mode
• The status of the signaling contact is routed externally by means of floating relay contacts. This enables, for example, the module to be monitored via an input module from a controller.
• Monitoring via the Industrial Ethernet network;
  the following possibilities are available:
  • Remote via standard browser (Web-based management):
    Selection of SCALANCE X-300 switches via the network from a PC with browser
  • Remote via SNMP V1, V2c, V3:
    Secure integration of SCALANCE X-300 switches via the network into a network management system, e.g. SINEMA Server
  • Remote via PROFINET IO diagnostics:
    PROFINET diagnostic alarms from SCALANCE X-300 switches can be displayed using the relevant SIMATIC engineering tools and they can also be processed in the controller. The engineering outlay for the PLC and HMI have been drastically reduced due to the complete integration in the SIMATIC concept for system error messages.

Network management

The network management provides the following functions:

• Password-protected dial-up for "Administrator" (read and write authorization) and "User" (read only)
• Read-out of version and status information
• Setting the signal and standby mask and address information
• Fixed parameterization of the ports (data rates, half/full duplex)
• Setting parameters of the VLANs and multicast services
• Parameterization of the standby connections for a redundant ring link
• Setting of Rapid Spanning Tree parameters
• Parameter assignment for web management services
• Security
  • Ports can be connected or disconnected
  • Authentication in accordance with IEEE 802.1x
  • Support of Access Control List (ACL)
• Parameter assignment for user administration of SNMP V1, V2c, V3
• Output of statistics information
• Diagnosis of data traffic by means of a parameterizable mirror port with a standard commercial network analyzer
• Loading of new firmware versions or of the configuration data via the network by a TFTP server or directly via HTTP/HTTPS using a Web browser
• Saving the configuration data or log table via the network on a TFTP server

If faults occur in the network, the SCALANCE X-300 switch can independently send error messages (traps) to a network management system or also e-mails to a predefined network administrator.

Remote monitoring (RMON) provides the following functions:
The SCALANCE X-300 switch can collect statistics information according to the RMON groups 1 through 4. These include, for example, fault statistics that are kept for each port. This information can be read out through web-based management in the statistics sub-area.