-- Exhibit --
[edit class-of-service]
user@router# show
interfaces {
ge-0/0/2 {
unit 0 {
classifiers {
inet-precedence default;
}
}
}
}
-- Exhibit --
Referring to the exhibit, which type of classifier is being used in this CoS configuration?
Click on the arrows to vote for the correct answer
A. B. C. D.A
According to the provided configuration, the classifier being used in this CoS configuration is "inet-precedence default", which is a type of multifield classifier.
A classifier in Junos CoS is a mechanism that examines specific fields in incoming packets to determine how the packets should be treated. The classifier extracts one or more fields from the packet header and uses the values in those fields to assign a forwarding class or code point to the packet.
In this case, the "inet-precedence default" classifier is examining the IP precedence bits in the IP header of incoming packets. IP precedence is a three-bit field in the IP header that was originally used to prioritize packets on the internet. The field has been replaced by the Differentiated Services Code Point (DSCP) field in modern networks, but the Junos OS still supports IP precedence as a legacy feature.
The "inet-precedence default" classifier is a type of multifield classifier because it examines multiple fields in the packet header. In addition to the IP precedence bits, it also examines the source and destination IP addresses, the protocol number, and the source and destination port numbers. By default, the classifier assigns packets to the default forwarding class, which is usually best-effort.
In contrast, a behavior aggregate classifier groups packets based on a specific set of criteria, such as the destination IP address or the protocol type, and assigns them to a specific forwarding class. A policer classifier enforces a specific rate limit on packets that match certain criteria. A forwarding policy classifier applies a specific forwarding policy to packets that match certain criteria.
Therefore, option C (multifield) is the correct answer for this question.