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服务质量
有些应用无法适应网络碰巧提供的任何带宽，因此服务质量首先从分类法入手：弹性应用可随延迟伸缩，而实时应用则会失效；随后要求各条流用令牌桶参数——速率与深度——来描述自身，并以两种方式构建保障：集成服务逐跳为每条流保留状态，采用由接收方发起的信令协议和准入控制，虽优雅却被自身状态压垮；区分服务则在边缘将分组标记为不同类别，赋予每跳行为，对延迟敏感的流量采用加速转发，并以分级丢弃优先级提供确保转发，用逐流承诺换取保持简单的核心路由器。
1. Who Needs Guarantees
Who Needs Guarantees
2. Describing a Flow
Describing a Flow
3. The Grand Reservation
The Grand Reservation
4. Classes Instead of Contracts
Classes Instead of Contracts
5. Elastic and not
Which applications are called elastic, and why?
6. The bucket's arithmetic
A flow is shaped by a token bucket with rate MB/s and depth MB. What is the most it can send in a 10-second interval?
7. Why the receiver asks
In integrated services signaling, why does the receiver rather than the sender initiate the reservation?
8. What killed the grand reservation
Why did per-flow integrated services fail to deploy in the Internet core?
9. The edge-core split
In differentiated services, where do classification, metering, and policing happen?
10. Two behaviors
How do expedited forwarding and assured forwarding differ?
11. The shaping pair
A token bucket characterizes a flow with which two parameters?
12. The backward request
In integrated services signaling, senders distribute path messages downstream while which party sends reservation messages upstream?
13. The soft expiry
Integrated services keeps reservations as what kind of state, refreshed periodically and removed silently when unrefreshed?
14. The per-hop name
Differentiated services defines the treatment interior routers give marked packets as what behaviors?