Device Interface
Polycom, Inc.
16
● VPNPassThrough
– If disabled, blocks all VPN traffic. The default is enabled.
These features take effect if the firewall is enabled. Otherwise, they’ll take on their respective default values.
Port Forwarding
You can define as many as 20 port forwarding rules on the device. For each rule, specify a range of ports
and designate receiving LAN IP address. You can also specify a rule for each that specifies if it should only
apply to packets transported over UDP, TCP, or both.
DMZ
The DMZ host is the default LAN client address that a packet received from the WAN side is forwarded to
when the router fails to find a matching LAN IP address or matching local process. If the firewall is enabled,
the packet is still subject to firewall inspection before forwarding to the DMZ host.
QoS
QoS (Quality of Service) refers to the prioritization of network traffic based on traffic type. On the HDA50,
QoS policy applies to upstream traffic (LAN-to-WAN) only. Downstream QoS is up to the ISP / upstream
routers and switches. The upstream traffic is prioritized according to its type of service as indicated by the
DiffServ/TOS bits in the IP header of each packet. In the QoS settings, you can map the 64 possible types
of service to one of the three priority classes: High, Medium, or Low. You also can specify the guaranteed
minimum upstream bandwidth for each priority class. LAN side clients indicate the desired priority class of
their outbound packets to the router by marking the DiffServ/TOS bits of their packets. See the
section for more details.
In addition to the three priority classes, a fourth priority class known as the Restricted
class is available. The
Restricted class has the highest priority among the four classes. The guaranteed bandwidth for the
Restricted class is set separately with its own parameter in the configuration.
The total guaranteed bandwidth allocated to all the four priority classes is equal to the total available
bandwidth, specified in
UpStreamBandwidth
parameter in the QoS settings.
VLAN Support in Router Mode
In router mode, the HDA50 can support VLAN (802.1Q) on the WAN side. If you enable VLAN, the incoming
packets on WAN that don’t belong to the same VLAN are dropped. All outgoing packets on WAN are tagged
with the VLAN ID. The VLAN support is transparent to the devices on the LAN side. The router removes the
VLAN tag when forwarding packets to the LAN side.
LAN Switching Features
You can set the HDA50 to act as a 3-port switch. One of the ports is internal, while the two external ports
(labeled as Internet and LAN) connect to other devices. This is the Bridge mode. In this mode, all the router
features, such DHCP server, firewall, and port forwarding, won’t take effect. In this case, the QoS policy
provides native voice traffic the highest priority (this behavior isn’t configurable).
