Draytek Vigor VigorAccess IVD User Manual page 13

Version: 1.5
High speed Internet Service
IVD aggregates DSL subscribers and terminates the encapsulated type ATM cell. Users can
easily access Internet through the IP backbone network. IPDSLAM supports PPPoE, DHCP, static
IP connection methods and provides Transparent LAN connection methods. IVD can support
simultaneously PPPoE and DHCP connection methods on the same PVC.
PPPoE Connection Mode
IVD supports bridged encapsulation at U interface defined by DSL Forum in WT-101 (Migration to
Ethernet Based DSL Aggregation, Rev.7, May. 2005) on Figure 4 stack b.
IVD supports filtering options in order to prevent L2 traffic between DSL customers connected to
the same DSLAM considering PPPoE environment (Intra-DSLAM filtering).
DSLAM part supports filtering options in order to prevent L2 traffic between DSL customers
connected to different DSLAMs considering PPPoE environment (Inter-DSLAM filtering)
considering N:1 VLAN forwarding.
Intra-DSLAM and Inter-DSLAM filters of the DSLAM is capable to be disabled partly or entirely
IVD provides positive Ethertype filtering with the following Ethertype values in upstream direction:
‧ 0x8863: PPPoE discovery
‧ 0x8864: PPPoE session
Positive filtering means, that DSLAM transmits Ethernet frames only with the defined Intertype
values.
IVD can filter Ethernet Broadcast frames in downstream direction.
IVD provides capabilities to prevent BRAS MAC spoofing.
IVD provides capabilities to prevent end user spoofing and end user blocking.
DHCP Access method
The DSLAM supports bridged encapsulation at U interface defined by DSL Forum in WT-
101(Migration to Ethernet Based DSL Aggregation, Rev.7, May. 2005) on Figure 4 stack a.
DSLAM supports filtering options in order to prevent L2 traffic between DSL customers connected
to the same DSLAM considering DHCP environment (Intra-DSLAM filtering).
DSLAM supports filtering options in order to prevent L2 traffic between DSL customers connected
to different DSLAMs considering DHCP environment (Inter-DSLAM filteringconsidering N:1 VLAN
forwarding.
Intra-DSLAM and Inter-DSLAM filters of the DSLAM are capable to be disabled partly or entirely
on VLAN basis.
DSLAM provides positive Ethertype filtering with the following Ethertype values in upstream
direction:
‧ 0x0800: IP
‧ 0x0806: ARP
Positive filtering means, that DSLAM transmits Ethernet frames only with the defined Intertype
values.
IVD can filter Ethernet Broadcast frames in downstream direction.
IVD provides capabilities to prevent BRAS (Gateway) MAC spoofing.
IVD provides capabilities to prevent end user spoofing and end user blocking.
Technical specification of Ethernet DSLAM
DSLAM can filter any traffic originates from the DSL endpoints before a valid DHCP IP address
assigning.
After a valid DHCP IP address assigning the DSLAM transmits only traffic originates from the
given source MAC/IP is stored during IP assigning.
DSLAM supports DHCP Option 82 insertion.
DSLAM supports DHCP relay with Option 82 insertion.
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