Question 1

Which of the following are characteristics of DSCP? (Choose two)

Accepted Answer

A)  DSCP is part of the Layer 3 header. 
B)  DSCP is a 6-bit field. 
C)  DSCP specifies eight different priorities. 
D)  DSCP specifies four precedence levels. 
E)  DSCP is part of the Layer 2 header
F) DSCP specifies 128 different per-hop behaviors.

Question 2

According to the SAP-ingress QoS policy shown, which of the following statements about processing of the packets by policers 3 and 4 is TRUE?

Accepted Answer

A)  Policer 3 forwards packets as out-of-profile when its PIR bucket has 4000 tokens. 
B)  Policer 3 starts discarding low-priority packets when its PIR bucket has at least 3000 tokens. 
C)  Policer 4 forwards all its packets as out-of-profile. 
D)  Policer 4 starts discarding low-priority packets when its PIR bucket has at least 3000 tokens.

Question 3

The network QoS policy shown below is applied properly to a Nokia 7750 SR acting as a transit Label Switch Router (LSR) for a given MPLS tunnel. A packet is received inside the MPLS tunnel with EXP=4, dot1p=4, and DSCP=AF. Which forwarding class is assigned to this packet?

Accepted Answer

A)  L2 
B)  H1 
C)  AF 
D)  BE

Question 4

Which of the following statements regarding buffer pool allocation are FALSE? (Choose two)

Accepted Answer

A)  Each network egress port receives its own buffer pool. 
B)  Each SAP-egress port receives its own buffer pool. 
C)  All SAP-ingress ports on the same MDA share a buffer pool. 
D)  All the network ingress ports on the same MDA share a buffer pool. 
E)  Each network ingress port on the same MDA receives its own buffer pool.

Question 5

A physical port has three associated buffer pools. Which of the following buffer pool combinations is associated to a physical port?

Accepted Answer

A)  Access ingress, access egress, network egress 
B)  Access ingress, network ingress, network egress 
C)  Port ingress, port egress, shared bi-directional 
D)  Port ingress, port egress, network egress 
E)  Port ingress, network ingress, network egress

Question 6

Both SAP-ingress 10 and policer-control-policy "CFHP" have been applied to a service SAP ingress. What is the maximum bandwidth allocated to policer 2?

Accepted Answer

A)  10000 Kbps 
B)  15000 Kbps 
C)  20000 Kbps 
D)  30000 Kbps

Question 7

Which of the following statements about network QoS policies is FALSE?

Accepted Answer

A)  Classification rules must specify both an FC and a profile for the packets. 
B)  A network policy is applied at a physical port. 
C)  Classification is performed with behavior-aggregate statements only. 
D)  Match criteria can be chosen from dot1p, DSCP, and EXP fields in the packet.

Question 8

Which of the following statements about CFHP policing hierarchy is FALSE?

Accepted Answer

A)  The root arbiter can be the parent of a tier 2 arbiter. 
B)  A tier 1 arbiter can be the parent of a policer. 
C)  A child policer can have a priority level from 0 to 10. 
D)  Weight is used by a parent arbiter to allocate bandwidth among children of equal level

Question 9

On the Nokia 7750 SR, what is the maximum number of queues that a single SAP-ingress policy can support in a VPLS?

Accepted Answer

A)  16 
B)  8 
C)  32 
D)  48 
E)  56

Question 10

On a Nokia IOM 3, how is buffer memory allocated per forwarding complex?

Accepted Answer

A)  512 MB ingress, 512 MB egress 
B)  256 MB ingress, 256 MB egress 
C)  1 GB dynamically allocated between ingress and egress. 
D)  768 MB dynamically allocated between ingress and egress. 
E)  768 MB, with a minimum of 256 MB ingress and egress, and an additional 256 MB dynamically allocated.

Question 11

Click the exhibit button below. A network operator has configured the SAP-ingress policy below. Ping traffic is expected in queue 3. However, the network operator notices that all traffic is placed in queue 1. What is the most probable reason for this?

Accepted Answer

A)  The default forwarding class for all traffic, including ICMP, is BE, which is placed in queue 1. 
B)  The SAP has been shut down. 
C)  The IP-match criteria has been misconfigured for ICMP traffic. 
D)  Queue 3 has no rate or CIR configured and thus cannot hold any packets. 
E)  The SAP-ingress policy has not been applied to the SAP.

Question 12

What is the 6-bit binary representation of DSCP value AF21?

Accepted Answer

A)  010011 
B)  100010 
C)  010001 
D)  001100 
E)  010010

Question 13

Which of the following statements are TRUE? (Choose two)

Accepted Answer

A)  The primary contributors to latency are distance, scheduling, and congestion. 
B)  The weighted round robin scheduling algorithm will result in more delay for high priority traffic than the regular round robin algorithm. 
C)  The round robin scheduling algorithm will result in less jitter for low priority traffic than a strict priority scheduler. 
D)  Packet loss can be reduced by decreasing the amount of buffer space available to a queue. 
E)  Latency can be reduced by increasing the amount of buffer space available to a queue.

Question 14

When using an egress port scheduler, which scheduling loop priority are orphaned queues serviced on?

Accepted Answer

A)  1st 
B)  8th 
C)  9th 
D)  17th

Question 15

An egress port scheduler applied to an Ethernet port has a configured bandwidth of 100 Mbps. All frames transmitted on the port are 80 bytes. What is the aggregate transmit bandwidth of all queues using the port scheduler?

Accepted Answer

A)  100Mbps * 20/(80 + 20) = 20 Mbps 
B)  100Mbps * 80/(80 + 20) = 80 Mbps 
C)  100Mbps 
D)  100+ 100 * 20/(80 + 20) = 120 Mbps

Question 16

A profile-mode queue is configured with the following attributes: MBS = 10 KB, CBS = 5 KB and High-Priority-Only = 30%. Assume there is no CBS overbooking, and the slope-policy is disabled. If the current queue depth is 8 KB, what will happen to an in-profile packet?

Accepted Answer

A)  It will be discarded because the high-priority-only threshold is exceeded. 
B)  It will be stored in the queue's reserved buffer space and become out-of-profile. 
C)  It will be stored in the queue's reserved buffer space and remain in-profile. 
D)  It will contend for shared buffer space with packets from other queues.

Question 17

A default network policy is applied to all router interfaces associated with network ports.

Accepted Answer

A) True 
 B)False

Question 18

The SAP-ingress policy shown below is applied properly to a Nokia 7750 SR. A traffic stream is received from an IP address of 192.168.2.200 with DSCP and dot1p set to EF and 4, respectively. Which forwarding class and priority level is used for this traffic stream?

Accepted Answer

A)  FC H1, high 
B)  FCH1, low 
C)  FCAF, high 
D)  FCAF, low

Question 19

Which of the following statements about the bandwidth allocation criteria used by an egress port scheduler is TRUE?

Accepted Answer

A)  The available bandwidth of the port is divided in a strict priority over its children. 
B)  Expedited queues must be serviced before best-effort queues. 
C)  Orphaned queues are serviced on the 8th scheduling priority. 
D)  The configured CIR dictates the maximum port bandwidth that can be allocated during the within-CIR pass for that level.

Question 20

Which of the following statements describes a queue's weight parameter that is used in the hierarchical scheduling?

Accepted Answer

A)  The weight specifies the priority of the queue during scheduling up to its CIR. 
B)  The weight specifies the priority of the queue during scheduling above-CIR, up to its PIR. 
C)  The weight is used to determine how this queue and other queues or schedulers at the same CIR-level share available CIR bandwidth at that level. 
D)  The weight is used to determine how this queue and other queues or schedulers at the same level share available above CIR bandwidth at that level.

Exam 1: Nokia Scalable IP Networks