4A0-107 Practice Exam Questions with Answers Nokia Quality of Service Certification

It enables CFHP.

It more scalable than using policers.

It allows a separate set of queues/policers for each VLAN on a port.

It allows a set of queues to be shared among multiple SAPs.

Real-time

Assured

Best-effort

Self-generated

An egress unicast queue defined in a network queue policy

An ingress unicast queue defined in a SAP-ingress policy

An ingress multipoint queue defined in a SAP-ingress policy

An ingress multipoint queue defined in a network queue policy

When a packet arrives, the PIR bucket depth is checked and the packet is discarded if this bucket is full.

The CIR bucket of a policer is the reserved portion of its PIR bucket.

The CIR bucket of a policer has two thresholds: CBS and HPO.

Packets processed by the PIR bucket at an average rate above PIR will be forwarded as out-of-profile.

PIR = 5 Mbps, CIR = 0 Mbps

PIR= 4 Mbps, CIR = 1 Mbps

PIR= 6 Mbps, CIR = 4 Mbps

PIR= 6 Mbps, CIR = 1 Mbps

An arbiter can adjust the CIR of its child policers.

An arbiter rate-limits the collective output of several policers towards each egress FFPC.

An arbiter can adjust the bandwidth assigned to its child arbiters and child policers.

An arbiter does not need to honor the configurations of its child policers.

When using profile-mode queues, traffic that is marked as in-profile on ingress and scheduled in the above-CIR loop will still be considered as in-profile at egress.

When an HQoS strategy using an egress port-scheduler has been deployed, Tier 1 receives its scheduling rates based on the amount of egress bandwidth available for each forwarding class.

The greater the difference between PIR and CIR rates in a queue, the less likely a CIR will be provided.

Packets scheduled out of high-priority queues in the default scheduler will have a lower chance of packet loss at the expense of incurring a higher probability of delay.

When using priority-mode queues, traffic that is marked as in-profile on ingress and scheduled in the above-CIR loop will be considered as in-profile at egress.

When queues use shared buffer space, buffers are more efficiently utilized.

Queues that use reserved buffer space will have memory available for their reserved portion.

When a queue is not using its reserved portion, other queues can use it.

Using reserved buffer space prevents a queue from being starved of buffer resources by other queues.

The egress port scheduler takes the ratio of requested bandwidth to total bandwidth request from all children. It allocates bandwidth fairly, using these percentages and not exceeding the egress interface speed.

The egress port scheduler allocates bandwidth based on a WRR distribution method that takes into account the CIR and PIR requested at each level and the max speed, either default or configured, on egress.

The egress port scheduler allocates bandwidth on a first come, first served distribution method that takes into account the total CIR and PIR requested at each level and the max PIR requested from a single level.

The egress port scheduler will limit the bandwidth offered to the egress port based on the over-subscription factor, provisioned under the router interface, while using a WRR scheduler for the remaining bandwidth.

The egress port scheduler will use the Russian Dolls Method to allocate bandwidth to each level of requested bandwidth. HPO-Only is automatically set to 100%, allowing only high priority traffic to be buffered during congestion.

An IES SAP

A VPLS SAP

A network port

AVPRN SAP

An access port

It is a parent scheduler.

It is the top-level scheduler.

It can allocate up to 50 Mbps of bandwidth to scheduler "low" since the bandwidth is not used by another Tier 3 scheduler.

It is a child scheduler.

It can only have queues as children.

All self-generated traffic is assigned into forwarding class NC by default.

Ingress self-generated traffic is stored in CPM queues and egress self-generated traffic is stored in IOM queues.

The self-generated packets will be marked with a default DSCP value.

The self-generated packets will be marked with default EXP bits.

It will be discarded because the high-priority-only threshold is exceeded.

It will be queued but re-marked as "out-of-profile."

It will be queued in the reserved portion of the buffer pool and remain "in-profile."

It will be queued in the shared portion of the buffer pool but contend for shared buffer space with packets from other queues.

It will be queued in the shared portion of the buffer pool but may be dropped if the buffer utilization exceeds the start-average value of the low slope.

Classification rules must specify both an FC and a profile for the packets.

A network policy is applied at a physical port.

Classification is performed with behavior-aggregate statements only.

Match criteria can be chosen from dot1p, DSCP, and EXP fields in the packet.

SAP-ingress

FFPC

SAP-egress

network-egress

In order to mark Layer 2 traffic, sgt-qos will set various ToS bits.

DSCP bits can be set per application, per routing instance.

The DSCP marking stays nc1 for all applications. Only the internal FC is manipulated across different applications.

In order to mark Layer 2 self-generated traffic, network interfaces must be set to dot1Q.

The internal forwarding class for self-generated traffic is set once and applied to the base router and all VPRN instances.

SAP-ingress only

SAP-egress only

SAP-ingress and SAP-egress

Network ingress

Network egress

Negative jitter results in a smaller than expected interval between transmitted packets.

Jitter does not have any effect on the quality of video applications.

Serialization delay is not affected by congestion.

Queuing delay is a fixed form of delay in networks.

An SLA is used to provide automated, real-time testing and alarming for throughput, latency, and jitter across a provider's network.

An SLA is an agreement between a customer and a provider that dictates the treatment of customer traffic across the provider's network.

An SLA allows customers to control all traffic within the service provider's network by prioritizing their traffic over others as desired.

An SLA allows a customer to pre-mark traffic and ensure that traffic is treated as per the agreement within the provider's network.

An SLA is a standard set of network QoS policies that a provider shares to all its customers, allowing them to better understand the treatment of traffic within the provider's network.

Set the queue’s CBS to 0

Set the queue’s MBS equal to the CBS

Set the queue’s high-priority-only equal to the MBS

Set the queue’s MBS to 0

Set the queue’s high-priority-only to 0

TRUE

FALSE

The default forwarding class defined in the SAP-egress policy.

The forwarding class inherited from network ingress classification.

Best Effort.

If there is no match, packets will be dropped.

8

3

5

6

DiffServ reserves resources dynamically using the RSVP protocol.

DiffServ only requires packets to be classified into forwarding classes at the first network hop.

DiffServ provides granular differentiation and superior fairness because it processes traffic streams individually.

DiffServ is more scalable it treats traffic streams as aggregates.

512 MB ingress, 512 MB egress

256 MB ingress, 256 MB egress

1 GB dynamically allocated between ingress and egress.

768 MB dynamically allocated between ingress and egress.

768 MB, with a minimum of 256 MB ingress and egress, and an additional 256 MB dynamically allocated.

IP Precedence

Dot1p

Forwarding class

EXP

It will be stored in the reserved buffer space and remain out-of-profile.

It will be stored in the reserved buffer space and become in-profile.

It will contend for shared buffer space with packets from other queues.

It will be discarded because the high-priority-only threshold has been reached.

The larger the configured MBS value, the lower the amount of shaping performed.

When policing is enabled on the SAP-ingress, all traffic is considered as in-profile.

Setting the CIR to 1000 and the PIR to max will enable shapeless policing at 1 Mbps within the SAP-egress policy.

Configuring MBS to equal CBS will disable shaping.

Setting the CIR and PIR to equal values disables soft-policing.

PIR

CIR

MBS

burst-limit