Comms gear aids bandwidth management

Edited by the Engineeringtalk editorial team Dec 9, 2005

Jetnet 4000 from Korenix supports VLAN and IGMP snooping that can help manage bandwidth even if the traffic increases dramatically.

The Jetnet 4000 from Korenix supports VLAN and IGMP snooping that can help manage bandwidth even if the traffic increases dramatically.

Via software, VLAN groups devices into a logical subgroup within a LAN regardless of the physical LAN segment to which they are attached.

VLAN protects industrial devices or systems from unauthorised access.

With VLAN functions, devices from a different LAN cannot communicate or access a LAN, providing extra security to the network.

VLAN functions can restrain the traffic within a VLAN.

It ensures that the traffic only circulates within a sub-domain without broadcasting over the entire network.

By doing so, network performance can be improved.

When an industrial device is physically moved to another location, it can stay on the same VLAN without any hardware reconfiguration.

IGMP (Internet Group Management Protocol) plays a role in industrial automation, especially for video over IP applications.

IGMP may be used with some field bus protocols over Ethernet, such as Siemens Profinet, Rockwell Ethernet/IP and Foundation Fieldbus HSE.

These industrial Ethernet protocols use publisher/subscriber communications models by multicasting packets over the network.

For this reason, multicasting traffic floods in a network since a switch cannot determine which multicasting strings belong to which group of users; it simply broadcasts over the entire network.

It can consume a lot of bandwidth if many servers are multicasting and sending streams to a certain segment.

The purpose of IGMP snooping is to restrain multicasting traffic in a switched network.

By filtering the multicasting traffic and sorting it to corresponding group of devices, a switch forwards messages only to the interface that is interested in the traffic.

It ensures that the right data will be only sent to the right destination, reducing the total amount of traffic on the network.

The Jetnet 4000 series includes four models - 4008 (8x10/100baseTX), 4008f (6x10/100base, 2x100baseFX), 4005 (5x10/100baseTX) and 4005f (4x10/100base, 1x100baseFX).

All support web configuration and network redundancy ring topology.