传统的Internet提供的是没有QoS保证的、尽力而为的服务。其实在lPv4包中已经定义了服务类型字段,包括优先级、吞吐量、延迟、可靠性等,只要 (23) 处理该字段,就可提供QoS保证。MPLS是一种更通用的QoS保证机制,其基本思想可简述为 (24) 。
A. 交换机
B. 路由器
C. 服务器
D. 客户端
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具有止血、抗炎、抗菌、抗瘤等作用的是
A. 紫草素
B. 丹参醌Ⅰ
C. 大黄素
D. 番泻苷A
E. 大黄素蒽酮
One of the most widely used routing protocols in IP networks is the Routing Information Protocol(RIP).RIP is the canonical example of a routing protocol built on the (71) algorithm.Routing protocols in internetworks differ slightly from the idealized graph model.In aninternetwork,the goal of the routers to forward packets to various (72) . Routers running RIP send their advertisement about cost every (73) seconds.A router also sends an update message whenever an update from another router causes it to change itsrouting table. It is possible to use a range of different metrics or costs for the links in a routing protocol.RIP takes the simplest approach,with all link costs being equal (74) Thus it always tries tofind the minimum hop route.Valid distances are 1 through (75) .This also limits RIP torunning on fairly small networks.
A. computers
B. routers
C. switches
D. networks
不稳定的化合物是
A. 紫草素
B. 丹参醌Ⅰ
C. 大黄素
D. 番泻苷A
E. 大黄素蒽酮
以下程序的执行结果是________。 #include<iostream.h> #include<iomanip.h> void main() cout.fil(’*’): cout.width(10); cout<<setiosflags(ios::hex)<<160<<endl; cout.width(8); cout<<160<<endl; cout.width(4): cout<<160<<endl;