User manual

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6.3.4 ALG
SIP (Session Initiation Protocol, RFC3261) is the protocol of choice for most VoIP
(Voice over IP) devices to initiate communication. A SIP ALG (Application Layer
Gateway) assists VoIP packet traffic from a SIP-compliant IP phone or VoIP gateway
to passthrough a NAT enabled router.
To enable the SIP ALG select the SIP Enabled checkbox, enter an UDP port value
(default is 5060) and click Save/Apply.
NOTE: ALG is only valid for SIP protocol running on UDP port 5060.
6.4 Security
To display this option, the Firewall checkbox must be enabled in at least one PVC
shown on the Advanced WAN Setup screen.
NOTE: For a more technical discussion of this topic, see Appendix A: Security.
6.4.1 MAC Filtering
NOTE: This function is only available when in bridge mode. Other connection
modes use IP Filtering (pg. 47) which performs a similar function.
Each network device has a unique 48-bit MAC address. This can be used to filter
(block or forward) packets based on the originating device ID. MAC filtering policy
and rules can be set by following the procedure below.
The policy FORWARDED means that all MAC layer frames will be FORWARDED
except those matching the rules specified in the following table. BLOCKED means
that all MAC layer frames will be BLOCKED except those matching the rules
specified in the following table. The default policy is FORWARDED. This can be
changed by clicking the Change Policy button.