[c-nsp] VLANS.....

[Devendra Vyas]

im totally confused over this topic and request you all to give some
time and clarify it if possible some of the answers i already know
vaguely and if you can reconfirm then will be helpful--
 
 How many types of VLANS are there and what distinguishes them???
 
well one internet site list foll. types of vlans--
 
port based
mac-based
layer 3 based
ip multicast
rule based
802.1q based
 
 
port and mac- based look simple enough and port based ones are the
ones we define on any L2 switch
 i.e.,
untagged ports and no 802.1q tags.....the filtering being done on the
L2 switch VLAN Filter database.--am i right here??--so there are no
VLAN headers here..the switch filter database distinguishes the
traffic between vlan x and vlan y
 
what is the Layer 3 based Vlan????
 
is this the one we have in cisco boxes-- diff vlans for diff. teams 
with each vlan spanning one subnet .etc..but even in this the
membership is port based.
 
what is a layer 3 vlan??
 
what is the tagged Vlan--the port traffic is tagged with a 802.1q vlan
id header???


thanks in advance and excuse for asking a basic question..but im confused... 

sadly there is no book or site on the net whch really explores the
VLAN topic in depth they all talk the usual stuff about
VTP/VMPS....etc.etc.....noboy clarifies the basic concepts...

rgds.
devendra vyas