Introduction
Overview
Router and Host Behaviors with DSCP Marking An IP
The DSCP is used for prioritizing transmission bandwidth. For example, when a router becomes congested, it uses the DSCP values of queued packets to decide which ones to drop, if necessary.
Routers can also use the DSCP to
Unlike VLAN tags, DSCP markers do not add to the traffic, because the DSCP marker is carried in an existing field of the IP packet.
Summary
In the DiffServ model, each
The first is traffic conditioning. Traffic conditioning reduces load peaks and consequent queueing delays. It assures that when the source node generates data faster than the adapter can send it, the most important traffic goes out first.
The second is marking, where sources place a VLAN or DSCP priority tag in their packets so that infrastructure equipment can decide which packets should be sent first and which should be dropped first.
Transmission priority (reserved and maximum bandwidth allocation) is of limited use as a control. Since the transmission priority isn’t carried with the packet, its usefulness ends at the first router. VLAN marking propagates through the
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