3Com Baseline 2848-SFP Plus User Manual

Also see for 2848 SFP - Baseline Switch Plus: Datasheet Release note

Contents

Configuring VLANs 35A tagged port is sometimes referred to as an uplinkport. The two terms refer to the same feature.If a port is already an untagged member of VLAN 0,making it an untagged memeber of VLAN 1 willdisassociate it from VLAN 0. The same result happensfrom VLAN 1 to VLAN 0.Delete VLANsClick the Remove button to remove the selected VLANgroup from the current list.1 In VLAN ID, click the ID of the VLAN group that youwant to delete.2 Click Remove.If any port is assigned to this VLAN group as untagged,it will be reassigned to VLAN group 1 as untagged.Forwarding Tagged/Untagged FramesEach port on the Switch is capable of passing tagged oruntagged frames.The following describes how the Switch will handletagged and untagged frames.■ When a port receives a tagged frame with a VLAN IDand the port is a member (untagged or tagged) ofthat VLAN, the frame is accepted. Otherwise the ifthe port is not a member of that VLAN, the frame isdiscarded.■ When a port receives an untagged frame and theport is an untagged member of a VLAN, the frame isaccepted and assigned to that VLAN ID. Otherwise ifthe port is not an untagged member of any VLAN,the frame is discarded.The Switch will only forward a frame to ports that aremembers (tagged or untagged) of the VLAN to whichthe frame is assigned. If the port is an untaggedmember, the egress frame will be stripped of the VLANtag and forwarded as untagged. However, if the port isa tagged member, the egress frame is forwarded astagged.Sample VLAN ConfigurationsTo illustrate how you can segment network devices thatare connected to the Switch, the following sampleconfigurations are provided.Setting Up Two VLANs on the Same SwitchFigure 14 illustrates how you can set up a simple VLANon the Switch using untagged connections.