Answer: D 

Explanation: 

ISL has no native VLAN concept because it places the entire Ethernet frame in the payload of an ISL frame. Native VLANs is an 802.1Q specific concept 

Answer: A 

Answer: B 

Explanation: 

The EIGRP IPv6 VRF Lite feature provides EIGRP IPv6 support for multiple VRFs. EIGRP for IPv6 can operate in the context of a VRF. The EIGRP IPv6 VRF Lite feature provides 

separation between routing and forwarding, providing an additional level of security because no communication between devices belonging to different VRFs is allowed unless it is explicitly configured. The EIGRP IPv6 VRF Lite feature simplifies the management and troubleshooting of traffic belonging to a specific VRF. The EIGRP IPv6 VRF Lite feature is available only in EIGRP named configurations. 

Reference: http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipv6/configuration/15-2mt/ipv6-15-2mt-book/ip6-eigrp.html#GUID-92B4FF4F-2B68-41B0-93C8-AAA4F0EC1B1B 

Answer: D 

Explanation: 

MED is an optional nontransitive attribute. MED is a hint to external neighbors about the preferred path into an autonomous system (AS) that has multiple entry points. The MED is also known as the external metric of a route. A lower MED value is preferred over a higher value. Example at reference link below: 

Reference: http://www.cisco.com/c/en/us/support/docs/ip/border-gateway-protocol-bgp/13759-37.html 

Answer: B,C,F 

Explanation: 

Cisco High-Level Data Link Controller (HDLC) is the Cisco proprietary protocol for sending data over synchronous serial links using HDLC. Cisco HDLC also provides a simple control protocol called Serial Line Address Resolution Protocol (SLARP) to maintain serial link keepalives. For each encapsulation type, a certain number of keepalives ignored by a peer triggers the serial interface to transition to the down state. For HDLC encapsulation, three ignored keepalives causes the interface to be brought down. By default, synchronous serial lines use the High-Level Data Link Control (HDLC) serial encapsulation method, which provides the synchronous framing and error detection functions of HDLC without windowing or retransmission. 

Reference: http://www.cisco.com/c/en/us/td/docs/routers/access/800/819/software/configuration/Guide/ 819_SCG/6ser_conf.html#78662 

Answer: E 

Explanation: 

Passive monitoring metrics include the following: 

. Delay: Cisco PfR measures the average delay of TCP flows for a given prefix or traffic class. Delay is the measurement of the round-trip response time (RTT) between the transmission of a TCP synchronization message and receipt of the TCP acknowledgement. 

. Packet loss: Cisco PfR measures packet loss by tracking TCP sequence numbers for each TCP flow; it tracks the highest TCP sequence number. If it receives a subsequent packet with a lower sequence number, PfR increments the packet-loss counter. Packet 

loss is measured in packets per million. 

. Reachability: Cisco PfR measures reachability by tracking TCP synchronization messages that have been sent repeatedly without receiving a TCP acknowledgement. 

. Throughput: Cisco PfR measures TCP throughput by measuring the total number of bytes and packets for each interesting traffic class or prefix for a given interval of time. 

Reference: http://www.cisco.com/c/en/us/products/collateral/ios-nx-os-software/performance-routing-pfr/product_data_sheet0900aecd806c4ee4.html 

Answer: C 

Explanation: 

By default, every link is an IS-IS network has a metric of 10. 

Answer: C,D,E 

Explanation: 

Cisco PfR selects an egress or ingress WAN path based on parameters that affect application performance, including reachability, delay, cost, jitter, and Mean Opinion Score (MOS). 

Reference: http://www.cisco.com/c/en/us/products/collateral/ios-nx-os-software/performance-routing-pfr/product_data_sheet0900aecd806c4ee4.html 

Answer:  

Answer: A,C