VLANs

Changing the management VLAN can be used to restrict management access to a specific set of users.

6.1.5 Edge and Trunk Port Types

Each port can be configured to take on a type of Edge or Trunk.

Edge Type

An Edge port attaches to a single end device (such as a PC or IED) and carries traffic on a single pre-configured VLAN, the native VLAN.

Trunk Type

Trunk ports are part of the network and carry traffic for all VLANs between switches. Trunk ports are automatically members of all VLANs configured in the switch.

The switch can “pass through” traffic, forwarding frames received on one trunk port out another trunk port. The trunk ports must be members of all the VLANs the “pass through” traffic is part of, even if none of those VLANs are used on edge ports.

Frames transmitted out the port on all VLANs other than the port’s native VLAN are always sent tagged.

Note: Sometimes it may be desirable to manually restrict the traffic on the trunk to a certain group of VLANs, for example when: the trunk connects to a device (such as a layer 3 router) that supports a subset of the available VLANs. Trunk port can be prevented from being a member of the VLAN by including it in the VLAN’s Forbidden Ports list.

Port Type

VLANs

PVID

Usage

Supported

Format

 

 

 

 

Untagged

VLAN Unaware networks – All frames are sent and

Edge

1 (Native)

received without the need for VLAN tags.

 

Configured

Tagged

VLAN Aware networks – VLAN Traffic domains are

 

 

 

enforced on a single VLAN

 

 

 

 

 

 

Switch-to-Switch connections – VLANs must be

 

 

 

manually created and administered or can be

Trunk

All

Tagged or

dynamically learned through GVRP.

Configured

Untagged

Multiple-VLAN end devices – Implement

 

 

 

 

connections to end devices that support multiple

 

 

 

VLANs at the same time.

6.1.6 VLAN Ingress and Egress Rules

Ingress Rules

These are the VLAN ingress rules, i.e. the rules applied to all frames when they are received by the switch:

ROS™ v3.5

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RS400

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RuggedCom RS400 manual Edge and Trunk Port Types, Edge Type, Trunk Type, Vlan Ingress and Egress Rules, Ingress Rules