What is the difference between port group and VLANs? (2024)

FAQs

What is the difference between a port and a VLAN? ›

Both VLAN and port isolation are used to make part of devices independent in a space for protection, but VLAN is used to isolate broadcast, and the IP segment of users in the same VLAN is the same and share the data. If make the port isolation, they can not communicate even if they are in the same IP segment.

Port-based VLAN is the most common type, where each port on a network switch is assigned to a particular VLAN. Tag-based VLAN uses special tags to identify packets that belong to different VLANs, and it is more flexible than port-based VLAN.

You can create a portgroup that is associated with multiple VLAN IDs, for example a single portgroup with ID 20,30,50,70. Because I have always created portgroups but with a VLAN ID, associated with each portgroup.

Private VLAN, also known as port isolation, is a technique in computer networking where a VLAN contains switch ports that are restricted such that they can only communicate with a given uplink. The restricted ports are called private ports. Each private VLAN typically contains many private ports, and a single uplink.

While LAN is used to connect a group of devices such as computers and printers to a server via cables, VLANs allow multiple LANs and associated devices to communicate via wireless internet.

A virtual LAN (VLAN) is a logical overlay network that groups together a subset of devices that share a physical LAN, isolating the traffic for each group. A LAN is a group of computers or other devices in the same place -- e.g., the same building or campus -- that share the same physical network.

Virtual LANs (VLANs) allow network administrators to subdivide a physical network into separate logical broadcast domains. On a standard Layer 2 network, all hosts connected to a switch are members of the same broadcast domain; and broadcast domains can only be physically separated across different switches by routers.

VLAN-enabled ports are generally categorized in one of two ways: tagged or untagged. These may also be referred to as "trunk" or "access" respectively. The purpose of a tagged or "trunked" port is to pass traffic for multiple VLANs, whereas an untagged or "access" port accepts traffic for only a single VLAN.

The switches covered in this guide allow up to 2048 (vids up to 4094) VLANs of all types. UsingVLAN tagging, ports can belong to multiple VLANs of all types.

For a given VLAN you can assign up to 32 IP addresses.

Can a port be part of 2 VLANs? ›

An access port can join only one VLAN. The VLAN to which the access port belongs is the PVID of the port. A trunk or hybrid port can carry multiple VLANs, and you can configure a PVID for the port.

NOTE: A switch supports a maximum of 4096 VLANs, among which VLANs 0 and 4095 are reserved for system use, and VLAN 1 is the default VLAN. Therefore, you can only create VLANs 2 to 4094.

VLAN trunking and access mode are two ways of configuring switch ports to connect devices in different VLANs. VLANs are logical groups of network devices that share the same broadcast domain and security policies, regardless of their physical location.

Quick Definition: A protected port is a network port that does not forward traffic to other protected ports on the same switch, even if they belong to the same VLAN. Activating this feature protects networks by limiting hacker access in the case of a cyber-attack.

Disadvantages of Private VLANs:

Limited Inter-VLAN Communication: Private VLANs restrict communication between devices within the same VLAN, which might be a disadvantage in scenarios where certain devices need to communicate freely. Limited Device Support: Not all network devices support Private VLANs.

An access port is a switch port that is a member of only one VLAN. There are two parts to configuring an access port: creating the VLAN in the switch's VLAN Database and assigning the switch port to a VLAN.

Ports on multiple devices can belong to the same VLAN. Traffic moving between ports in the same VLAN is bridged (or switched). Traffic moving between different VLANs must be routed. A static VLAN is an 802.1Q-compliant VLAN, configured with one or more ports that remain members regardless of traffic usage.

By default, all switch ports are part of VLAN 1. VLAN 1 contains control plane traffic and can contain user traffic.

An access port can have only one VLAN configured on the interface; it can carry traffic for only one VLAN. A trunk port can have two or more VLANs configured on the interface; it can carry traffic for several VLANs simultaneously.