Which of the following is not a characteristic of Cisco Express Forwarding？（）A、The adjacency table is populated from a router’s ARP cacheB、CEF does not require the first packet of a data flow to be process switchedC、CEF maintains the Forward Information Base and the adjacency tableD、CEF can be enabled with the interface command ip cefE、The FIB is populated from a router’s IP routing tableF、On most router platforms CEF is enabled by default
Which of the following is not a characteristic of Cisco Express Forwarding？（）
- A、The adjacency table is populated from a router’s ARP cache
- B、CEF does not require the first packet of a data flow to be process switched
- C、CEF maintains the Forward Information Base and the adjacency table
- D、CEF can be enabled with the interface command ip cef
- E、The FIB is populated from a router’s IP routing table
- F、On most router platforms CEF is enabled by default
相关考题：
阅读下面的短文，回答问题 [When an IP packet arrives at a router, generally the router looks at the destination address of the packet, and forwards the packet to one of its network interfaces. The forwarding decision is usually done by looking up the destination address from another data structure called a forwarding table. The forwarding table is created by the router using the routing table and possible routing policies existing in the router. The router then creates a table where it lists which networks are accessible through which of the routers network interfaces. An IP router looks at every IP packet individually and does the forwarding decision on a packet-by-packet basis. If something changes in the routers routing table, a packet can take a different route from a preceding packet even if it has the same destination.] From the paragraph above，we can see that the router （ ） a forwarding table according to the routing table and possible routing policies existing in the router. When an IP packet arrives at a router, the （ ） part of packet is normally checked by the router. An IP router checks every IP Packet individually and makes the forwarding decision based on （ ）.A．is generating B．generate C．is generated D．generates A．forwarding table B．network interfaces C．routing policies D．destination address A．the destination address and network interfaces B．forwarding table and network interfaces C．the destination address and forward table D．routing policies and routing table
The router SIS-R has been configured in a CIS network. As a network administrator, you were required to enable MPLS on that router.Which of the following description is making sense on the basis of the output information?（）A. CEF switching is only needed to forward labeled packets.B. CEF switching is needed on both ingress and egress interfaces on which MPLS is enabled.C. Interface-level CEF switching is needed only on egress interfaces that are sending IP packets on which the egress LSR performs the label imposition process.D. Interface-level CEF switching is needed only on ingress interfaces that are receiving IP packets on which the ingress LSR performs the label imposition process.
Cisco Express Forwarding (CEF) is mainly used to increase packet switching speed, reducing the overhead and delays introduced by other routing techniques, increasing overall performance.Which of the following concerning CEF is recommended by Cisco?（）A. Use default Layer 4 hash in core.B. Use default Layer 3 hash in distribution.C. Use default Layer 4 hash in distribution.D. Use default Layer 3 hash in core and Layer 3 + Layer 4 hash in distribution layer.
Which option correctly identifies the Cisco IOS switching methods in descending order from the fastest method to the slowest method？（）A、CEF， distributed CEF （dCEF）， fast switching， process switchingB、distributed CEF （dCEF）， CEF， fast switching， process switchingC、fast switching， process switching， distributed CEF （dCEF）， CEFD、process switching， fast switching， distributed CEF （dCEF）， CEFE、process switching， distributed CEF （dCEF）， CEF， fast switchingF、process switching， CEF， distributed CEF （dCEF）， fast switching
Your boss， Miss ，is interested in CEF. What should you tell her？ （）A、The FIB lookup is based on the Layer 3 destination address prefix （shortest match）.B、The adjacent table is derived from the ARP table.C、The FIB table is derived from the IP routing table.D、When the adjacency table is full， a CEF TCAM table entry points to the Layer 3 engine to redirect the adjacency.E、CEF IP destination prefixes are stored in the TCAM table， from the least specific to the most specific entry.F、When the CEF TCAM table is full， packets are dropped.
Which of the following is not a characteristic of fast switching？（）A、Fast switching reducesa routers CPU utilization， compared to process switchingB、All packets of a flow， except for the first packet， use the information in the fast cacheC、It can be enabled with the interface command ip route-cacheD、Fast switching uses a fast cache maintained in a router’s control planeE、The fast cache contains information about how traffic from different data flows should beforwardedF、Even though the fast switching is enabled， the first packet of a flow is still process switched
Cisco Express Forwarding has been enabled on router TK1. With CEF， prefixes that require exception processing can be cached with one of which four special adjacencies？ （）A、KickB、DropC、ForwardD、NullE、DiscardF、GleanG、Express
Which of the following data structures exist on a router for the OSPF routing protocol？（）A、OSPF topology tableB、OSPF interface tableC、OSPF routing information baseD、OSPF link-state databaseE、OSPF adjacency tableF、OSPF neighbor table
Which two table types are CEF components？（）A、forwarding information baseB、adjacency tablesC、neighbor tablesD、caching tablesE、route tables
Which two statements describe the difference between JUNOS Software for securityplatforms and a traditional router？（）A、JUNOS Software for security platforms supports NAT and PAT； a traditional router does not support NAT or PAT.B、JUNOS Software for security platforms does not forward traffic by default； a traditional router forwards traffic by default.C、JUNOS Software for security platforms uses session-based forwarding； a traditional router uses packet-based forwarding.D、JUNOS Software for security platforms performs route lookup for every packet； a traditional router performs route lookup only for the first packet.
Which process plays a major role in the creation of the CEF adjacency table？ （）A、Address Resolution Protocol （ARP）B、PDU header rewriteC、NetFlow switchingD、hello packet exchange
Which of the following are not BGRP data structures？ （Choose all that apply.）（）A、EIGRP database tableB、EIGRP CEF tableC、EIGRP neighbor tableD、EIGRP adjacency tableE、EIGRP interface tableF、EIGRP topology table
Which of the following commands provides data plane information required to forward a packet toa specific ip address？（）A、sh ip routeB、sh ip cef 〈ip_address〉C、sh adjacency 〈ip_address〉D、sh ip route 〈ip_addres$〉E、sh ip adjacency 〈/p_address〉F、sh ip cef 〈mac_addrQss〉〈ip_address〉
For best packet switching performance with crypto, what is the recommend packet switching path in a Cisco Teleworker Router?（）A、Process SwitchingB、Silicon Switching C、Cisco Express Forwarding (CEF) SwitchingD、Autonomous Switching
Which of the following is an unlikely reason for the ARP process to fail？（）A、CEF switching is disabled on the switchB、The source device and destination device are in different VLANsC、The VLAN is excluded from the trunkD、The host is connected to the switch through an IP phoneE、A faulty cable from host to switch or between switchesF、The trunking encapsulation type is inconsistent on the two ends of the link
多选题Which of the following are not BGRP data structures？ （Choose all that apply.）（）AEIGRP database tableBEIGRP CEF tableCEIGRP neighbor tableDEIGRP adjacency tableEEIGRP interface tableFEIGRP topology table
多选题Which of the following data structures exist on a router for the OSPF routing protocol？（）AOSPF topology tableBOSPF interface tableCOSPF routing information baseDOSPF link-state databaseEOSPF adjacency tableFOSPF neighbor table
多选题Cisco Express Forwarding has been enabled on router TK1. With CEF， prefixes that require exception processing can be cached with one of which four special adjacencies？ （）AKickBDropCForwardDNullEDiscardFGleanGExpress
单选题Which of the following commands provides data plane information required to forward a packet toa specific ip address？（）Ash ip routeBsh ip cef 〈ip_address〉Csh adjacency 〈ip_address〉Dsh ip route 〈ip_addres$〉Esh ip adjacency 〈/p_address〉Fsh ip cef 〈mac_addrQss〉〈ip_address〉
单选题Which process plays a major role in the creation of the CEF adjacency table？ （）AAddress Resolution Protocol （ARP）BPDU header rewriteCNetFlow switchingDhello packet exchange
多选题Your boss， Miss ，is interested in CEF. What should you tell her？ （）AThe FIB lookup is based on the Layer 3 destination address prefix （shortest match）.BThe adjacent table is derived from the ARP table.CThe FIB table is derived from the IP routing table.DWhen the adjacency table is full， a CEF TCAM table entry points to the Layer 3 engine to redirect the adjacency.ECEF IP destination prefixes are stored in the TCAM table， from the least specific to the most specific entry.FWhen the CEF TCAM table is full， packets are dropped.
单选题Cisco Express Forwarding (CEF) is mainly used to increase packet switching speed, reducing the overhead and delays introduced by other routing techniques, increasing overall performance.Which of the following concerning CEF is recommended by Cisco?（）AUse default Layer 4 hash in core.BUse default Layer 3 hash in distribution.CUse default Layer 4 hash in distribution.DUse default Layer 3 hash in core and Layer 3 + Layer 4 hash in distribution layer.
多选题Which two statements describe the difference between JUNOS Software for securityplatforms and a traditional router？（）AJUNOS Software for security platforms supports NAT and PAT； a traditional router does not support NAT or PAT.BJUNOS Software for security platforms does not forward traffic by default； a traditional router forwards traffic by default.CJUNOS Software for security platforms uses session-based forwarding； a traditional router uses packet-based forwarding.DJUNOS Software for security platforms performs route lookup for every packet； a traditional router performs route lookup only for the first packet.
单选题Which of the following is not a characteristic of Cisco Express Forwarding？（）AThe adjacency table is populated from a router’s ARP cacheBCEF does not require the first packet of a data flow to be process switchedCCEF maintains the Forward Information Base and the adjacency tableDCEF can be enabled with the interface command ip cefEThe FIB is populated from a router’s IP routing tableFOn most router platforms CEF is enabled by default
单选题Cisco Express Forwarding （CEF） is mainly used to increase packet switching speed， reducing theoverhead and delays introduced by other routing techniques， increasing overall performance.Which of the following concerning CEF is recommended by Cisco？（）A Use default Layer 4 hash in core.B Use default Layer 3 hash in distribution.C Use default Layer 4 hash in distribution.D Use default Layer 3 hash in core and Layer 3 + Layer 4 hash in distribution layer.
单选题Which option correctly identifies the Cisco IOS switching methods in descending order from the fastest method to the slowest method？（）ACEF， distributed CEF （dCEF）， fast switching， process switchingBdistributed CEF （dCEF）， CEF， fast switching， process switchingCfast switching， process switching， distributed CEF （dCEF）， CEFDprocess switching， fast switching， distributed CEF （dCEF）， CEFEprocess switching， distributed CEF （dCEF）， CEF， fast switchingFprocess switching， CEF， distributed CEF （dCEF）， fast switching
单选题For best packet switching performance with crypto, what is the recommend packet switching path in a Cisco Teleworker Router?（）AProcess SwitchingBSilicon Switching CCisco Express Forwarding (CEF) SwitchingDAutonomous Switching