The network is being flooded with invalid Layer 2 addresses，

A to be flooding ;

B being flooded ;

C being flooding

TCP functions at the Open System Interconnection(OSI)(61)layer, or Layer 4. Its chief responsibility is to ensure(62)end-to-end connectivity. IP, located one layer down, at the OSI network layer, or Layer 3, communicates the addresses of each(63)sender and receiver to the routers along the way. Routers and Layer 3 switches can read IP and other Layer 3(64). This information, combined with routing tables and other network intelligence, is all it takes to get(65)the room or around the world via TCP/IP.

A．transpose

B．translate

C．transmit

D．transport

CDP is being used throughout the Ezonexam network. What are two reasons why the Ezonexam network administrator would use CDP? (Choose two)

A. To determine the status of network services on a remote device

B. To obtain the IP Address of a connected device in order to telnet to the device

C. To verify the type of cable interconnecting two devices

D. To verify Layer 2 connectivity between two devices when Layer 3 fails

E. To obtain VLAN information from directly connected swticehs

F. To determine the status of the routing protocols between directly connected routers

G. To support automatic network failover during outages

A. IP addresses can be managed from a central point

B. Computers can automatically get new addressing when moved to a different network segment

C. Media Access Control addresses can be changed automatically

D. The network speed can automatically adjust based on the type of traffic being generated

E. The HOSTS file on the computer can be validated for proper entries

Most IP layer-based proxy mechanisms，such as network address translation (NAT)，only supportuni-directional proxy，from the internal network to external network(the Interned．The proxvestablishes the communication channel by (71) IP addresses．The IP addresses must be (72) ．These proxy mechanisms prevent applications that must establish return data channels from establishing their data channels，such as，multimedia applications．IP layer-based proxy mechanisms need additional software (73) for each application that uses (74) channels． SOCKS identifies communication targets through domain names，overcoming the restriction of Usina private IP addresses．SOCKS can use domain names to establish communication between separate LANs，with (75) IP addresses．

(66)

A．manufacturing

B．manipulating

C．conduct

D．implement

Both bridges are switches are being used throughout the Ezonexam LAN. Which of the following statements are true regarding bridges and switches in this network?

(Choose 3)

A. Switches are primarily software based while bridges are hardware based.

B. Switches usually have a higher number of ports than most bridges.

C. Bridges are frequently faster than switches.

D. Bridges define broadcast domains while switches define collision domains.

E. Both bridges and switches forward Layer 2 broadcasts.

F. Both bridges and switches make forwarding decisions based on Layer 2 addresses.

● TCP/IP communication protocol contains four layers. From bottom to top, the four layers are __(71)__.

（71）A．network interface layer, internet layer, transport layer and application layer

B．internet layer, network interface layer, transport layer and application layer

C．network interface layer, transport layer, network interface layer and application layer

D．application layer, transport layer, internet layer and network interface layer

TCP functions at the Open Systems Interconnection(OSI)transport layer, or Layer 4. Its chief responsibility is to ensure reliable end-to-end connectivity. IP, located one layer （1）, at the OSI network layer, or Layer 3,communicates the addresses of each packet’s sender and receiver to the routers along the way .Routers and Layer 3 switches can read IP and other Layer 3 protocols. This information, combined with routing tables and other network intelligence, it takes to get across the room or around the world（2）TCP/IP.

The routing process begins with an IP address that is（3）to the sending end station. End stations may be assigned permanent IP addresses or they may borrow them as needed from a Dynamic Host Configuration Protocol(DHCP)server or other service. If the sending end station determines that the destination address is not local, the packet goes to a first-hop router, typically one that is close and has been reassigned to the（4）. The router inspects the packet’s IP address and performs a route table lookup to see if the destination end station resides on the local(physically connected)network, typically called an IP subnet. An IP subnet usually is assigned to each of the router’s network interfaces. If the destination IP address is local, the router searches an internal store of IP addresses and local-device media access control(MAC)addresses. This store is known as the Address Resolution Protocol(ARP) cache. ARP is the universal tool for（5）IP addresses to MAC addresses. If the destination’s MAC address appears, the router installs that MAC address in the packet header(removing its own MAC address because that’s no longer needed)and sends the packet to the destination end station.

（1）A. up

B. down

C. sideward

D. back-fence

（2）A. via

B. through

C. by

D. through out

（3）A. special

B. especial

C. unique

D. particular

（4）A. accepter

B. sender

C. router

D. server

（5）A. searching

B. looking

C. locating

D. matching

TCP/IP communication protocol contains four layers． From bottom to top, the four layers are __（71）__．

A.network interface layer, internet layer, transport layer and application layer

B.internet layer, network interface layer, transport layer and application layer

C.network interface layer, transport layer, network interface layer and application layer

D.application layer, transport layer, internet layer and network interface layer

Which layer-function is mostly implemented in a network adapter（ ）。

A.Physical layer and link layer

B.Network layer and transport layer

C.Physical layer and network layer

D.Transport layer and application layer