Description of functions
Our unique FRNT (Fast Recovery of Network Topology) technology is the fastest network recovery protocol on the market. FRNT is able to reconfigure a redundant ring network consisting of up to 200 switches within 20 ms of the initial failure, regardless of network load. FRNT is a protocol supported by other Westermo switches like the Lynx, Wolverine and Viper series meaning that different types of Westermo switch can be configured in the ring.
Our unique FRNT (Fast Recovery of Network Topology) technology is the fastest network recovery protocol on the market. FRNT is able to reconfigure a redundant ring network consisting of up to 200 switches within 20 ms of the initial failure, regardless of network load. FRNT is a protocol supported by other Westermo switches like the Lynx, Wolverine and Viper series meaning that different types of Westermo switch can be configured in the ring.
To provide compatibility with industry standard redundancy protocols the RedFox also supports STP and RSTP.
Multicast data packets are the perfect way to transmit data to multiple 'consumers' on a network. If for instance fifty users wish to view a video feed it would congest a network completely if every data frame had to be sent fifty times. A single multicast packet is all that is transmitted by the data 'producer'.
The problem however with multicast packets is that by definition they must be made available to all parts of a network in case they are required. To allow multicasting to work in an Ethernet network, switches have to stop acting as switches and pass the data to all ports. This becomes a huge problem if there are low speed data connections in your network as these can become flooded with potentially unwanted traffic.
IGMP Snooping is a method that actually 'snoops' or inspects IGMP traffic. The protocol will only enable multicast streams to switch ports that have requested to 'join' the feed. In this way switches can control multicast data on networks. When using IGMP snooping in conjunction with redundancy protocols problems can occur when a network reconfigures. The network topology change by definition means that the IGMP data paths change. It is for this reason that Westermo have closely integrated our IGMP solution with FRNT to ensure that these delays do not occur.
RedFox features comprehensive VLAN support. This technique allows a large physical switched network to be divided into smaller more manageable logical networks or VLANs.
This has a number of benefits including increased security, increased network bandwidth and improved manageability.
Redfox allows VLANs to be allocated to particular switch ports meaning that access to certain network services can be restricted. This can be beneficial for security purposes but also it allows certain high bandwidth protocols to be isolated from the rest of the network.
By subdividing the physical network into VLANs broadcast traffic can be controlled within separate networks thus preventing broadcast storms affecting the whole network.
As VLANs can be centrally configured it is possible for a network manager to reconfigure a badly performing network centrally rather than having to physically plug and unplug cables out in the field.
Ethernet through its design is not deterministic, i.e. you cannot guarantee the transfer time of a data packet from one occasion to another. A switched network is subject to delays, which can vary from 10 ms to several ms due to the load, speed of the drop link, packet size, switch architecture and the number of switches between the server and client.
This previously made it impossible to use Ethernet for real time applications, such as motion control or highly complex industrial processes. These applications are now within the scope of Redfox.
RedFox contains four priority queues per port, where the queue handling is based on strict priority scheduling in order to offer maximum determinism for real time critical and latency sensitive data. This means that high priority data always has preference over low priority data. Priority is accomplished through layer 2 tagging based on IEEE802.1p and/or layer 3 based on IP ToS.
Head of line blocking prevention ensures that the switch does not become congested due to bottlenecks on a port caused by a highly loaded network. This can be the case when large amounts of multicast and broadcast traffic exist on a high speed part of the network. Low speed ports are unable to transmit the data fast enough to clear their buffer.
