●We have already covered the topic of network addresses. The first(71) in a block (in classes A,B,and C) defines the network address. In classes A,B,and C,if the hostid is all ls, the address is called a direct broadcast address. It is used by a (72) to send a packet to all hosts in a specific network. All hosts will accept a packet having this type of destination address. Note that this address can be used only as a (73)address in an lP packet. Note also that this special address also reduces the number of available hostid for each netid in classes A,B,and C.
In classes A,B,and C,an address with all Is for the netid and hostid (32 bits) defines a( 74) address in the current network.A host that wants to send a message to every other host can use this address as a destination address in an IP packet. However,a router will block a packet having this type ofaddress to confine the broadcasting to the (75) network. Note that this address belongs to class E.
(71) A.datagram
B.function
C.address
D.service
(72) A.router
B.switch
C.hub
D.firewall
(73)A.source
B.destination
C.local
D.remote
(74) A.unicast
B.multicast
C.broadcast
D.anycast
(75) A.neighbor
B.next
C.remote
D.local
第1题:
A、If it's a small amount we write it off as bad debt. For larger sums we…
B、I've got to hurry.
C、I have already done that.
第2题:
A. lot
B. Few
C. A few
D. Too few
第3题:
Where shall we have the meeting?()
A. The first conference room is spacious
B. The first conference room isn't good
C. In the first conference room
第4题:
We should very much like to help you in this matter, but we have already cut our prices down to the absolute minimum.We think you will find that our competitors are offering a product of considerably lower quality in order to compete at this price.(英译中)
第5题:
Networks can be interconnected by different devices in the physical layer networks can be connected by (71) or hubs.which just move the bits from one network to an identical network.One layer up we find bridges and switches which operate at data link layer.They can accept (72) ,examine the MAC address and forward the frames to a different network while doing minor protocol translation in the process in me network layer,we have routers that can connect two networks,If two networks have (73) network layer,the router may be able to translate betweenthe packer formats.In the transport layer we find transport gateway,which can interface between two transport connections Finally,in the application layer,application gateways translate message (74) .As an example,gateways between Internet e-mail and X,400 e-mail must (75) thee-mail message and change various header fields.
(68)
A.reapers
B.relays
C.packages
D.modems
第6题:
第7题:
第8题:
A:Where shall we have the meeting? B:()
AThe first conference room is spacious
BThe first conference room isn't good
CIn the first conference room
第9题:
翻译:Now that we have already made an inquiry on your articles, will you please make an offer before the end of this month?
第10题:
There are 3 steps to confirm whether a range of IP address can be summarized. When of thefollowing is used in each of these 3 steps?()
第11题:
The first number in the contiguous block of addresses
The last number in the contiguous block of addresses
The size of the contiguous block of addresses
The subnet mask of the original network address
第12题:
Women who are pregnant, especially for the first time.
Women who dream of having babies for the first time.
Women who already have children.
Women who have just got babies for the first time.
第13题:
A、In the first conference room.
B、The first conference room is spacious.
C、The first conference room isn’t good.
第14题:
A had been; have seen
B have been; have seen
C had been; had seen
D have been; had seen
第15题:
()separate cover, we have already sent you samples () various sizes of shoes.
A、Below,of
B、Under,of
C、By,of
D、By,including
第16题:
It is already twenty years ____ we ____ to know Mr. White in Paris.
A. after … got
B. after …have got
C. since … got
D. since …have got
第17题:
A. Redistribution must be enabled mutually (in both directions) to work correctly.
B. auto - summary causes the OSPF routes redistributed into EIGRP to be summarized; thus the OSPF network 116.16.34 is summarized to 116.3 4.0.0, which is already covered by the EIGRP protocol.
C. Default metrics are not configured under EIGRP.
D. Both routing protocols must have unique autonomous system numbers for redistribution to function correctly.
第18题:
第19题:
第20题:
A:Where shall we have the meeting? B:()
第21题:
If business had been carried out to our satisfaction,we()to renew the Agency Agreement.
第22题:
of
in
on
at
第23题: