Traditional Internet access methods like dial-up were so slow that host computers were connected to the dial-up. (6) at the customer premise over slow (7) ports. PPP was designed to run directly over these serial links. But with the advent of broadband Internet (8) technologies such as ADSL and cable modems there has been a considerable increase in the bandwidth delivered to the end users. This means that the host computers at the customer premise connect to the (9) or cable "modem" over a much faster medium such as Ethernet. It also means that multiple (10) can connect to the Internet through the same connection.

A:cables B:hosts C:servers D:modems

Networks can be interconnected by different devices. In the physical layer, networks can be connected by (66) or Hubs, which just move the bits from one network to an identical network. One layer up we find bridges and swiches, which operate at data link layer. They can accept (67) ,examine the MAC address, and forward the frames to a different network while doing minor protocol translation in the process. In the network layer, we have routers that can connect two netwoks. If two networks have (68) network layer, the router may be able to translate between the packet formats. In the transport layer we find transport gateway, which can interface between the two transport connections. Finally, in the application layer, application gateways translate message (69) . As an example, gateways between Internet e-mail and X. 400 e-mail must (70) the e-mail message and change various header fields.

A:reapers B:relays C:connects D:modems

Networks can be interconnected by different devices in the physical layer networks can be connected by (1) 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 (2) 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 (3) network layer, the router may be able to translate between the 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 (4) . As an example, gateways between Internet e-mail and X.400 e-mail must (5) the e-mail message and change various header fields.

A:reapers B:relays C:packages D:modems

Traditional Internet access methods like dial-up were so slow that host computers were connected to the dial-up （71） at the customer premise over slow （72） ports. PPP was designed to run directly over these serial links. But with the advent of broadband Internet （73）technologies such as ADSL and cable modems there has been a considerable increase in the bandwidth delivered to the end users. This means that the host computers at the customer premise connect to the （74） or cable "modem" over a much faster medium such as Ethernet.It also means that multiple （75） can connect to the Internet through the same connection.

A:cables B:hosts C:servers D:modems

Networks can be interconnected by different devices. In the physical layer networks can be connected by (31) 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 (32) , examine the MAC address and forward the frames to a different network while doing minor protocol translation in the process. In network layer, we have routers that can connect two networks. If two networks have (33) network layer, the muter may be able to translate between the 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 (34) . As an example, gateways between Internet e-mail and X.400 e-mail must (35) the e-mail message and change various header fields.

A:reapers B:relays C:packages D:modems

Networks can be interconnected by different devices. In the physical layer, networks can be connected by (41) 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 (42) , examine the MAC address, and forward the frames to a different network while doing minor protocol translation in the process. In the network layer, we have routers that can connect two networks. If two networks have (43) network layer, the router may be able to translate between the packet 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 (44) . As an example, gateways between Internet E-mail and X.400 E-mail must (45) the E-mail message and change various header fields.

A:reapers B:relays C:connectors D:modems

An internet is a combination of networks connected by （1）. When a datagram goes from a source to a （2）, it will probably pass many （3） until it reaches the routerattached to the destination network. A router receives a （4）from a network and passes it toanother network. A router is usually attached to several networks. When it receives a packet, towhich network should it pass the packet The decision is based on optimization: Which of theavailable（5） is the optimum pathway

A:modems B:routers C:switcher D:computers

An internet is a combination of networks connected by (26) ．When a datagram goes from a source to a (27) ，it will probably pass many (28) until it reaches the router attached to the destination network．A router receives a (29) from a network and passes it to another network．A router is usually attached to several networks．When it receives a packet，to which network should it pass the packet The decision is based on optimization：Which of the available (30) is the optimum pathway

A:modems B:routers C:switcher D:computers

An internet is a combination of networks connected by  （）  .When a datagram goes from a source to a  （） ，it will probably pass many  （）  until it reaches the router attached to the destination network．A router receives a  （）  from a network and passes it to another network．A router is usually attached to several networks．When it receives a packet，to which network should it pass the packet The decision is based on optimization： Which of the available  （）  is the optimum pathway.

A:modems B:routers C:switches D:computers