Which three practices are important to the implementation of a DiffServ QoS architecture？（） Because services are allocated throughout the network before the transmission of data begins， traffic classes can be guaranteed QoS services.。 Traffic classes are marked with Layer 2 markings to allow for more granularity in identifying traffic classes.。 Traffic classes are marked with Layer 3 markings to allow them to traverse different network types without loss of QoS information.。 Traffic classes allow networks to provide proper QoS treatment of packets without applications having to request services.。 Based upon the network capabilities， QoS markings are placed on packets as needed throughout the network to allow for proper QoS treatment of packets.。 QoS markings are placed on packets as close to the network edge as possible to allow distribution and core devices to determine QoS actions as quickly as possible.。
合作创新是指企业间、科研机构、高等院校之间的联合创新行为。合作各方有明确的合作目标、合作期限、合作规则，在技术创新的全过程或某些中间环节共同投入、共同参与、共享成果、共担风险。
变动成本法的优点主要包括（）、（）、（）、（）。
To ensure quality, what is the maximum end-to-end transit time in milliseconds on a voice network?（） 50。 100。 150。 200。 250。
以下选项中哪些不属于取保候审期间保证人应承担的保证义务（）。 监督被保证人遵守应当遵守的相关规定。 发现被保证人可能发生或已经发生违反规定的行为，及时向执行机关报告。 管理被保证人的日常生活。 教育被保证人改邪归正。
（）组词意义同语素义一致。
