Re: [LinkSec] RE: [802.1] P802.1ad Task Group ballot disposition
Mick,
As Mark pointed out, I did not request globally unique 24-32 bit
ID space for SVID. I claimed 24-32 bit space is needed in a
single Bridged LAN, which called an island.
According to the definition of VLAN described in clause 3.16 of 802.1Q-
1998, a VID holds a unique value in a Virtual Bridged LAN. So I thought
extension of ID space is needed for support of public service.
Please see ATM cell format. It has 8 bit VPI and 16 bit VCI in
UNI cell format. So, it totally has 24 bit ID space to
distinguish services, because nation wide public service needs
this quantity of ID space. And I think this is common sense for
providers.
And I think large ID space such as VPI/VCI and DLCI never compete
with IP address. If 24 bit SVID competes IP address space, 48 bit
MAC address is much dangerous. ;-)
Anyway, if .1ad assumes that the current 12 bit VID space may
be extended with another technology, clause 3.16 in 802.1Q should
be revised, because it explicitly define it hold a unique value
in a Bridged LAN as shown below.
3.16 VLAN
A subset of the active topology of a Bridged Local Area Network.
Associated with each VLAN is a VLAN Identifier (VID).
Muneyoshi Suzuki
Nippon Telegraph and Telephone Corp.