Which two statements are true about network voice traffic？ （

第1题：

Which two statements are true about the protocols that are used for transmitting voice traffic？（）

• A、RTP multiplexing is used to keep multiple phone conversations separate
• B、RTP provides end-to-end delivery services for voice traffic
• C、UDP is used to ensure a reliable transmission from sender to receiver
• D、RTP is used to provide resource reservation for the voice stream
• E、UDP provides multiplexing

第2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3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4题：

Which two statements about the QoS policy generation phase of the Cisco SDM QoS wizard are true？（）

• A、the SDM QoS wizard will create two real-time traffic classes to handle VoIP， voice signaling， and video packets
• B、the SDM QoS wizard will create three real-time traffic classes to handle VoIP， voice signaling， video， and video packets
• C、the SDM QoS wizard will create four real-time traffic classes to handle VoIP， voice signaling， video， and video streaming packets
• D、the SDM QoS wizard will create two business-critical traffic classes to handle transactional and  network management packets
• E、the SDM QoS wizard will create three business-critical traffic classes to handle transactional， network management， and routing packets
• F、the SDM QoS wizard will create four business-critical traffic classes to handle transactional， network management， routing， and best-effort packets

第5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6题：

Which two statements about an IDS are true？（）

• A、The IDS is in the traffic path.
• B、The IDS can send TCP resets to the source device.
• C、The IDS can send TCP resets to the destination device.
• D、The IDS listens promiscuously to all traffic on the network.
• E、Default operation is for the IDS to discard malicious traffic.

第7题：

Which two statements are true about L2TP tunnels?（） (Choose two.)

• A、Traffic is clear text
• B、Traffic is encrypted 
• C、They are initiated by the LNS
• D、They are initiated by the LAC

第8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9题：

Which two statements are true about the application of QoS in a converged network？（）

• A、end-to-end network delay times that exceed 50 ms for real-time traffic are considered unacceptable
• B、end-to-end network delay times that exceed 250 ms for real-time traffic are considered unacceptable
• C、end-to-end network delay is not a factor as long as the  delay is consistent
• D、some packet loss can be corrected by codec algorithms
• E、RSVP handles voice packet retransmission
• F、fragmentation is a result of packet loss

第10题：

Which two statements are true about trust boundaries？（）

• A、Classifying and marking traffic should be done as close to the traffic source as possible. 
• B、Classifying and marking traffic should be done at the distribution layer.
• C、Traffic is classified and marked as it travels through the network.
• D、If untrusted traffic enters a switch， it can be marked with a new QoS value appropriate for the policy in place.
• E、The trust boundary moves depending on the type of traffic entering the network.