Actiontec Wireless Broadband Router User Manual

The matching of packets by rules is connection-based, known as Stateful Packet Inspection (SPI), using the Router’s firewall mechanism. Once a packet matches a rule, all subsequent packets with the same attributes receive the same QoS param- eters, both inbound and outbound. Connection-based QoS also allows inheriting QoS parameters by some of the applications that open subsequent connections. For instance, QoS rules can be defined on SIP, and the rules will apply to both con- trol and data ports (even if the data ports are unknown). Applications that support such inheritance have an ALG in the firewall. They are:

SIP

MSN Messenger/Windows Messenger

TFTP

FTP

MGCP

H.323

Port triggering applications

PPTP

IPSec

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Actiontec electronic MI424-WR user manual MSN Messenger/Windows Messenger, Port triggering applications