User's Manual

Chapter 1 VLC Overview
VLC1324G User’s Guide
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Alarm LED
An ALM (alarm) LED lights when the VLC is overheated or the voltage readings are outside
the tolerance levels and turns off when the temperature or voltage has returned to a normal
level.
CFM
The IEEE 802.1ag Connectivity Fault Management (CFM) specification allows network
administrators to identify and manage connection faults. Through discovery and verification
of the path, CFM can detect, analyze and isolate connectivity faults in bridged LANs. This is
especially helpful when the route between a CO VDSL switch and one of its CPE goes
through switches owned by independent organizations.
IEEE 802.1Q Tagged VLAN
Your VLC uses the IEEE 802.1Q Tagged VLAN (Virtual Local Area Network), which allows
it to deliver tagged/untagged frames to and from its ports.
Subnet Based VLAN
Subnet based VLAN allows you to group traffic into logical VLANs based on the source IP
subnet you specify. When a frame is received on a port, the VLC checks if a tag is added
already and the IP subnet it came from. The untagged packets from the same IP subnet are then
placed in the same subnet based VLAN. One advantage of using subnet based VLANs is that
priority can be assigned to traffic from the same IP subnet.
xVLAN
xVLAN translates (changes) the VLAN IDs (VIDs) of subscriber traffic before sending it to
the service provider’s network. This lets you use unique VLANs for each subscriber but still
deploy all the CPE devices with the same VLAN configuration. xVLAN also supports
translating single-tagged frames to double-tagged frames.
Port Isolation
The VLC's port isolation feature allows each port to communicate with the uplink port but not
communicate with each other.
Isolation (per-VLAN)
Use isolation to block the VDSL2 subscribers in a specific VLAN from sending traffic directly
to each other.
IEEE 802.1x Port-based Authentication
The VLC supports the IEEE 802.1x standard for centralized user authentication and
accounting management through an optional network authentication (RADIUS) server.
Packet Filter
The VLC supports packet filtering based on protocol. You can configure the VLC to accept all
packets, accept PPPoE packets only or block any combination of the following protocols: IP,
ARP, DHCP, EAPOL, PPPoE, NetBios or IGMP.