User's Manual Part 3

03/24/09 - DRAFT
030-300554 Rev. C 166 March 2009
Verizon FiOS Router
(
Model 9100EM
)
User Guide
15.7.4 Differentiated Service Code Point (DSCP) Settings
If you click the Quality of Service link in the Advanced screen and then click DSCP Settings in the left submenu,
the following screen appears.
Familiarity with the Differentiated Services model is essential to understanding DSCP. Differentiated Services
(Diffserv) is a Class of Service (CoS) model that enhances best-effort Internet services by differentiating traffic by
users, service requirements, and other criteria. Packets are specifically marked, allowing network nodes to provide
different levels of service, as appropriate for voice calls, video playback, or other delay-sensitive applications, via
priority queuing or bandwidth allocation, or by choosing dedicated routes for specific traffic flows.
Diffserv defines a field in IP packet headers referred to as the Differentiated Services Codepoint (DSCP). Hosts or
routers passing traffic to a Diffserv-enabled network will typically mark each transmitted packet with an appropriate
DSCP. The DSCP markings are used by Diffserv network routers to appropriately classify packets and to apply a
particular queue handling or scheduling behavior to packets.
The Router provides a table of predefined DSCP values, which are mapped to 802.1p priority marking method. Any
of the existing DSCP setting can be edited or deleted, and new entries can be added. To add a new DSCP value,
press the New Entry link at the bottom of this screen.