What is the difference between PVID , untagged and tagged

businessuer

Firstly, how do I set a native vlan for a port in nebula switch?

Secondly, I understand that untagged means access in cisco, so why we can have multiple untagged vlan in 1 port?

Thirdly, what is PVID? Is it access vlan?

Fourthly, what is the difference between PVID and configuring as untagged vlan? 

Zyxel_Adam

Hi @businessuer,

Welcome to Zyxel community!
I will answer your question one by one as following:

1.  How do I set a native vlan for a port in nebula switch?

Kindly inform you that native vlan is PVID on Nebula switch.
Once you login to NCC web portal, go to Switch > Configure > Switch ports, and then click one port that you would like to set native vlan. 


I use port 1 as an example here, as you can see there is a PVID where you can put different vlan on it instead of default PVID 1. 


2. I understand that untagged means access in Cisco, so why we can have multiple untagged vlan in 1 port?

We cannot configure multiple untagged vlan on the same port of Nebula switch. 



3. What is PVID? Is it access vlan?

The description of PVID as below

As I described above, PVID is native VLAN for Nebula switch.
Trunk and Access VLAN is a VLAN type like you know on Cisco Switch.


4. What is the difference between PVID and configuring as untagged vlan?

PVID, as I described on question 1
Untagged vlan, as I described on question 3


Sincerely

Zyxel_Adam

Hi @businessuer,

Welcome to Zyxel community!
I will answer your question one by one as following:

1.  How do I set a native vlan for a port in nebula switch?

Kindly inform you that native vlan is PVID on Nebula switch.
Once you login to NCC web portal, go to Switch > Configure > Switch ports, and then click one port that you would like to set native vlan. 


I use port 1 as an example here, as you can see there is a PVID where you can put different vlan on it instead of default PVID 1. 


2. I understand that untagged means access in Cisco, so why we can have multiple untagged vlan in 1 port?

We cannot configure multiple untagged vlan on the same port of Nebula switch. 



3. What is PVID? Is it access vlan?

The description of PVID as below

As I described above, PVID is native VLAN for Nebula switch.
Trunk and Access VLAN is a VLAN type like you know on Cisco Switch.


4. What is the difference between PVID and configuring as untagged vlan?

PVID, as I described on question 1
Untagged vlan, as I described on question 3


Sincerely

businessuer

I still dont understand the difference between PVID and untagged vlan.

What happens if I put PVID 2 and untagged vlan as 2 both at the same time? 

Or is it better to put PVID as 1 (default) and untagged vlan as 2 at the same time?

Assume that vlan 2 is connected to a computer. 

Zyxel_Adam

Hi @businessuer ,

Well, for your question "What happens if I put PVID 2 and untagged vlan as 2 both at the same time?"

1. When you put VLAN 2 as untagged and PVID 2 on a specific port, the port forwards the packets of connected PC to VLAN 2 without tagging. 
2. When you put VLAN 2 as untagged and PVID 1(default) on a specific port, the connected PC can reach VLAN 1 only. 
   

You may think PVID in this way,

1. PVID is native VLAN.
2. PVID is access VLAN when you configure switchport on Cisco switch.

Don't be hesitate to inquire us if there is anything unclear. 

businessuer

I dont understand scenario 2.
If native vlan is 1 and access vlan is 2,

How will the uplink process the frame?
Diagram will be better

Zyxel_Adam

Hi @businessuer ,

Sorry for the wrong information of scenario 2,

When you put VLAN 2 as untagged and PVID 1(default) on a specific port, the connected PC can reach VLAN 1 only. 

My apology to make this confusion.
If there is anything still unclear, I will draw a diagram to help you for further understanding.

businessuer

Hi Nebula_Adam,

A diagram would be best. If you are free you can help me do it.

Zyxel_Tobias

Hi @businessuer

currently Adam is busy for a while. Are you fine, we provide diagram around 2/19, if you need it earlier, may I take your E-Mail and another Agent will re-check your requirement earlier?

Let me know.

Kind Regards,

Tobias

businessuer

19/2 will be ok

Zyxel_Adam

Hi @businessuer ,

Let me explain more explicit. 

Compare VLAN between Zyxel and Cisco:

When configuring VLAN on Zyxel switch (Standalone mode), you need to:
1. Create VLAN
2. Specify tagged or untagged port 
3. Configure PVID on a specific port (this action is the same as configuring access port for Cisco switch)


When configuring VLAN on Cisco switch, you need to:
1. Create VLAN
2. Configure access or trunk VLAN on a specific port (this action is similar to step 2 and 3 of Zyxel switch)


When configuring VLAN on Zyxel Nebula switch (Cloud mode), you need to:
1. Choose specific port(s)
2. Select access or trunk type (This action is the same as configuring Cisco switch)
2-1. If use access (untagged),  enter PVID (like native VLAN in Cisco Switch)

2-2. If use trunk (tagged), configure allowed VLANs you want (The default is allowed all) and PVID.


Scenario 1 : VLAN 2 (untagged port 1), PVID 1


Scenario 2 : VLAN 2 (untagged port 2), PVID 2


Hope it hopes and every clear =D

businessuer

When I configure zyxel switch in standalone mode:
1. Create VLAN
2. Specify tagged or untagged port 
3. Configure PVID on a specific port (this action is the same as configuring access port for Cisco switch)

Will step 1 and step 3 overlap with each other?

Let say :
in step 1  create vlan 2.
in step 2  make vlan 2 untagged but the original vlan 1 is also untagged.
in step 3 make this port a PVID of vlan 3.

Now what will happen? This is the confusion.

Will it be switchport access vlan 1 or 2 or 3 ?