Outline Network Layer and Internetworking The TCP/IP protocol suit ATM MPLS

Optimal Routing View routing as a “global” optimization problem Assumptions: – The cost of using a link is a function of the flow on that link

FLOW CONTROL QuickTime™ and a GIF decompressor are needed to see this picture. QuickTime™ and a Photo - JPEG decompressor are needed to see this picture. LIDS Flow control: end-to-end mechanism for regulating traffic between source and destination

Service times M/G/1 General independent Poisson arrivals at rate λ Service time has arbitrary distribution with given E[X] and E[X2] – Service times are independent and identically

Carrier Sense Multiple Access (CSMA) In certain situations nodes can hear each other by listening to the channel “Carrier Sensing” CSMA: Polite version of Aloha

An interesting property of an M/M/1 queue, which greatly simplifies combining these queues into a network, is the surprising fact that the output of an M/M/1 queue with arrival rate λ is a Poisson process of rate

When the receiver detects errors in a packet, how does it let the transmitter know to re-send the corresponding packet? Systems which automatically request the retransmission of missing

Queueing Systems Used for analyzing network performance In packet networks, events are random Random packet arrivals

4.1 网络信息管理简介 4.2 网络信息管理基本技术 4.3 网络信息的整理 4.4 个人网络信息查询系统的设计 4.5 个人数据库建立

施工测量也以地面控制点为基础，根据图纸上的建筑物的设计 尺寸，计算出各部分的特征点与控制点之间的距离、角度（或方位 角）、高差等数据，将建筑物的特征点在实地标定出来，以便施工 ，这项工作又称“放样”