T-VIPS CP560, User Manual

Page: 184 / 200

184 Quality of Service, Setting Packet Priority
CP560 DVB-T2 Gateway User’s Manual Rev. 2.2 (3686) ID: um_t2gateway
Layer 3 prioritisation may also be combined with MPLS where layer 3 routing is used in the
aggregation network and MPLS in the core network. The DSCP priority setting may be used
for MPLS tagging.
D.2.1 CP560 configuration
The number entered into the Type of service (TOS) field in CP560 IP TX configuration menu
defines all 8 bits. The value used should be in accordance with traffic engineering policy of the
network and should be in the range from 0 to 255.
D.3 Layer 2 priority
Prioritisation can also be supported in layer 2 using VLAN tags. The 802.1q VLAN tag has 3
bits for setting the Class of Service (COS). The operation is further defined in
[7] . The COS bits
will be handled the same ways as Diff-serve or precedence bits regarding packet classification
in the network.
D.3.1 CP560 configuration
The COS priority is entered in the VLAN configuration page in the CP560
IP TX
configuration
menu, in the field named
VLAN Priority
. A value in the range from 0 to 7 should be inserted.
This value will be directly transferred to 3 user priority bits in the VLAN header.
More information on quality of service issues and configuration can be found in the literature,
e.g. router configuration guides.