P.RG F4202N
© (2010) Pirelli Broadband Solutions S.p.A. All Rights Reserved. Proprietary Use Pursuant to Cover Page Instructions.
QoS Section
HBK 939800036-A1
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determine the priority that packets, traveling through the device, will receive.
QoS parameters (DSCP marking and packet priority) are set per packet, on an
application basis.
You can set QoS parameters using flexible rules, according to the following pa-
rameters:
Source/destination IP address, MAC address or host name
Device
Source/destination ports
Limit the rule for specific days and hours
The Router supports two priority marking methods for packet prioritization:
DSCP
802.1p Priority
The matching of packets by rules is connection-based, known as Stateful
Packet Inspection (SPI). Once a packet matches a rule, all subsequent packets
with the same attributes receive the same QoS parameters, both inbound and
outbound.
A packet can match more than one rule. Therefore:
The first class rule has precedence over all other class rules (scanning is
stopped once the first rule is reached).
The first traffic-priority (classless) rule has precedence over all other traffic-
priority rules.
There is no prevention of a traffic-priority rule conflicting with a class rule. In
this case, the priority and DSCP setting of the class rule (if given) will take
precedence.
Connection-based QoS also allows inheriting QoS parameters by some of the
applications that open subsequent connections. For instance, you can define
QoS rules on SIP, and the rules will apply to both control and data ports (even if
the data ports are unknown):
SIP
MSN Messenger/Windows Messenger
TFTP
FTP
MGCP
H.323
Port Triggering applications
PPTP
IPSec
