Traditional IP packet forwarding analyzes the____(1)____IP address contained in the network layer header of each packet as the packet travels from its source to its final destination．A router analyzes the destination IP address independently at each hop in the network．Dynamic ____(2)____protocols or static configuration builds the database needed to analyze the destination IP address(the routing table)．The process of implementing traditional IP routing also is called hop—by—hop destination—based____(3)____routing．Although successful，and obviously widely deployed，certain restrictions，which have been realized for some time，exist for this method of packet forwarding that diminish its____(4)____．New techniques are therefore required to address and expand the functionality of an IP—based network infrastructure．This first chapter concentrate on identifying these restrictions and presents a rew，architecture，known as multipIeprotocol____(5)____switching，that provides solutions to some of these restrictions．

(5)

A．const

B．cast

C．mark

D．label

按照施工合同文本的规定，承包人负责设计的图纸经工程师审查批准使用后，出现因设计责任的质量事故，则该项损失应由（）负责。

A.发包人

B.工程师

C.承包人

D.承包人与工程师共同