Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

Some questions about Generic Attribute Registration Protocol (GARP)

Recently I read 802.1D-2004 standard and I have some questions about Generic Attribute Registration Protocol (GARP),

these questons are as follow:

1.

This figure is GARP state machine:

gvrp_state.jpg

If device receives LeaveIn and it is in VA state, it is still in VA state; if device receives LeaveIn and it is in AA state, it will change to VA state. But if device receives LeaveIn and it is in QA state, it will change to VP state. Why device will change to VP state if it receives LeaveIn and it is in QA state ? I think it should also change to VA state instead of VP state. 

2.  According to the above GARP state machine figure in question 1, it can be seen that if device receives Join message and  subsequently receives Leave message, it will send Empty message . What is the use of Empty message ? Why does the standard describe it should send Empty message ?

3.

gvrp_state2.jpg

According to the above GARP state machine,  if device receives JoinEmpty and it is in VA state, it is still in VA state,

but if device receives ReqJoin and it is in VA state, the state of device is "-x-" . If the state of device is "-x-", it means that it is still in the same state. In other words, if device is in VA state and it receives JoinEmpty or ReqJoin, it is still in VA state.

But the state machine describes the result of receiving JoinEmpty and receiving ReqJoin with different ways. It desceibes the result of receiving ReqJoin is "-x-" instead of "VA".   Why doesn't this state machine describe that the device is in "VA state" if it receives ReqJoin ?

Thank you.

447
Views
0
Helpful
0
Replies
CreatePlease login to create content