To ensure voice packets are kept within the Committed Inform

第1题：

Which three statements are true about the data traffic characteristics of voice traffic？ （）

• A、latency must be kept below 150 ms
• B、latency is not a concern as long as jitter is kept below 30 ms
• C、voice packets do not require a specific type of queuing
• D、voice packets are rather small
• E、voice packets require TCP for rapid retransmission of dropped packets
• F、voice packets require a fairly constant bandwidth reserved for voice control traffic as well as forthe voice payload

第2题：

Which two statements are true about MLP interleaving？ （）

• A、 It fragments and encapsulates all packets in a fragmentation header.
• B、 Packets smaller than the fragmentation size are interleaved between the fragments of thelarger packets.
• C、 Packets larger than the fragmentation size are always fragmented， and cannot be interleaved，even if the traffic is voice traffic.
• D、 It fragments and encapsulates packets that are longer than a configured size， but does not encapsulate smaller packets inside a fragmentation header.

第3题：

第4题：

Why is QoS important in a converged network?（）

• A、Because data does not need to arrive intact, so data transfer rates can be variable
• B、Because lost voice-data packets must be retransmitted
• C、Because voice data packets should arrive quickly and sequentially, and with no lost data
• D、Because voice data packets must follow a single dedicated path through the network

第5题：

Which two statements are true about Voice over IP （VoIP） packet delivery in a digital infrastructure？ （）

• A、 Packets can arrive out of order.
• B、 Packets must take the same path to the destination.
• C、 Once packets are received at the destination router， the router performs sampling to ensure the quality of the voice traffic.
• D、 Packets can experience varying delays across the network.
• E、 Packets containing voice samples are sequentially numbered by default， allowing for reordering upon arrival at the terminal router along the path.

第6题：

Which two statements are true about voice packets in a LAN？ （Choose two.）  （）

• A、 Voice traffic data flow involves large volumes of large packets.
• B、 Because a packet loss involves a small amount of data， voice traffic is less affected by packet losses than traditional data traffic is.
• C、 Voice carrier stream utilizes Real-Time Transport Protocol （RTP） to carry the audio/media portion of VoIP communication.
• D、 Voice packets are very sensitive to delay and jitter.
• E、 Voice packets are encapsulated in TCP segments to allow for proper sequencing during delivery.

第7题：

To ensure voice packets are kept within the Committed Information Rate （CIR） of a Frame Relaylink， what should be used in the CPE？（）

• A、 prioritization
• B、 classification
• C、 fragmentation
• D、 traffic shaping

第8题：

第9题：

VOIP has been implemented at the main office of the Company network. Which two statements  are true about voice packets in a LAN？（）

• A、 Voice carrier stream utilizes Real-Time Transport Protocol (RTP) to carry the audio/media  portion of the VoIP communication.  
• B、 Voice traffic data flow involves large volumes of large packets.  
• C、 Because a packet loss involves a small amount of data, voice traffic is less affected by packet  losses than traditional data traffic is.  
• D、 Voice packets are encapsulated in TCP segments to allow for proper sequencing during  delivery. 
• E、 Voice packets are very sensitive to delay and jitter. 

第10题：

What are two major sources of delay that can be managed by QoS in voice-enabled networks？（）

• A、propagation delay
• B、voice packet serialization delay
• C、congested egress queues
• D、header overhead
• E、packets dropped because of CRC errors