ZyXEL Communications OLT2406, Руководство пользователя

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Chapter 24 VLAN Stacking
OLT2406 User’s Guide
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• If the VLAN stacking port role is Access Port , then the OLT adds the SP TPID tag to all incoming frames
on the service provider's edge devices (1 and 2 in the VLAN stacking example figure).
• If the VLAN stacking port role is Tunnel Port , then the OLT only adds the SP TPID tag to all incoming
frames on the service provider's edge devices (1 and 2 in the VLAN stacking example figure) that
have an SP TPID different to the one configured on the OLT. (If an incoming frame’s SP TPID is the
same as the one configured on the OLT, then the OLT will not add the tag.)
Priority refers to the IEEE 802.1p standard that allows the service provider to prioritize traffic based on the
class of service (CoS) the customer has paid for.
• On the OLT, configure priority level of the inner IEEE 802.1Q tag in the Port Setup screen.
• "0" is the lowest priority level and "7" is the highest.
VID is the VLAN ID. SP VID is the VID for the second (service provider’s) VLAN tag.
24.3.1 Frame Format
The frame format for an untagged Ethernet frame, a single-tagged 802.1Q frame (customer) and a
“double-tagged” 802.1Q frame (service provider) is shown next.
Configure the fields as highlighted in the OLT VLAN Stacking screen.
24.4 Configuring VLAN Stacking
Click Advanced Application > VLAN Stacking to display the screen as shown.
You can also use VLAN stacking on UNI ports. See Section 38.2.3 on page 308 for more information.
Table 65
Single and Double Tagged 802.1Q Frame Format
DA SA Len/Etype Data FCS Untagged
Ethernet frame
DA SA TPID Priority VID Len/Etype Data FCS IEEE 802.1Q
customer
tagged frame
DA SA SPTPID Priority VID TPID Priority VID Len/Etype Data FCS Double-tagged
frame
Table 66
802.1Q Frame
DA Destination Address Priority 802.1p Priority
SA Source Address Len/Etype Length and type of Ethernet frame
(SP)TPID (Service Provider) Tag Protocol IDentifier Data Frame data
VID VLAN ID FCS Frame Check Sequence