working principles of network operating system ppt

... on and off during a window of length t. Thus, with high probability X[0; t], which is the contribution of the source in a window of size t, takes only two values: zero if the source is off and ... numbers of sources of the different types. The acceptance region is now the intersection of the acceptance regions corresponding to each of the constraints. Assume that on the ‘interesting’ part of ... the right hand part of Figure 4.6. Each frequency of fluctuation defines a timescale of burstiness, i.e. an order of time over which significant changes are observed in the rate of the source, when

Ngày tải lên: 14/08/2014, 12:20

... and a mean rate of 1=2 kbps Let x denote the sum of the effective bandwidths of all type traffic Let y denote the sum of the mean rates of type traffic Then the constraints of the system are x Ä ... managing network resources 10.1 Notions of fairness In this and the following two sections, we adopt the following model of a network of elastic users We let L be a set of links and R be a set of routes, ... that the advantage of approaching the solution of SYSTEM by way of the NETWORK and USERr problems is that the network and users only need information to which they have access The network does not

Ngày tải lên: 14/08/2014, 12:20

... seen, network services are economic goods, which a network provides through use of its resources of links, switches, hardware, software and management systems This section introduces some of the ... billing are particularly costly The cost of selling a single copy of a piece of software is small compared to the cost of maintaining, monitoring and billing a network service It is not surprising ... the learning curve for this type of software is very steep Similarly, Microsoft Word commands a good price because of a network externality effect: the number of people who can exchange documents

Ngày tải lên: 14/08/2014, 12:20

... ISBN: 0-470-85130-9 24 NETWORK SERVICES AND CONTRACTS related to contracts for network services, focusing on issues of quality of service and performance. 2.1 A classification of network services At ... different networks. We see all these things in the Internet. For simplicity, we often refer to a large collection of cooperating networks that provide a given transport service as ‘the network? ??. ... Networks (20 02a) and (20 02b) The concepts of network service layering and quality of service are covered in the classic networking textbooks of Walrand (1998), Walrand and Varaiya

Ngày tải lên: 14/08/2014, 12:20

... management of the resources at the nodes of the network typically occurs on slow timescales (since SLAs should not change frequently) and it is the responsibility of the network manager (or of the ... television channels In most cases the cost of the content is a substantial part (about 40%) of the operating cost of the access network A final issue is the amount of risk involved in deploying new services ... A box of type i has weight wi and volume vi A box of type i has n times the relative effective usage of a box of type j if we are indifferent between packing box of type i or n boxes of type

Ngày tải lên: 14/08/2014, 12:20

... prices of $100 for each of the products, resulting in a total revenue of $400 Suppose now that he offers a new product that consists of the bundle of products A and B for a price of ... output of several smaller suppliers at less than the total of their costs. This is due both to production economies of scale (the average cost of production decreases with the quantity of a good ... is the present value of the quality difference of the services provided by networks i and j, and the third term is the present value of the difference in their operating costs Observe

Ngày tải lên: 14/08/2014, 12:20

... defined by the operating point of the multiplexer Think of Þon-off as a function of m, where without confusion we can write it as Þon-off m/, a concave function of m Note that the network. ... cost of these must be apportioned in an ad hoc way An example is the salaries of the members of the board of the company This overhead... charge per unit of time of a unit of effective ... (2003) A thorough discussion of the merits of LRIC for pricing access network services is in Economides (2000) For definitions of. .. make use of this type of pricing Section 8.5 presents

Ngày tải lên: 14/08/2014, 12:20

... advertises networks 6 and 7 to network 1 Similarly, when networks 2 and 3 peer, network 2 advertises networks 6 and 7 to network 3, and network 3 advertises network 8 to network ... of the other networks Let us consider networks 1 and 2 and the information exchanged between their edge routers Network 1 advertises network 5 to network 2, and network. .. network ... large networks, 1–4, offer transit services to smaller networks, 5 8 For instance, network 2 offers transit service to networks 6 and 7 To do so, networks 1–4 peer at a peering point Each network

Ngày tải lên: 14/08/2014, 12:20

... be able to offer lower prices to its customers. Yet because of interconnection with the large network its customers can reach the same population of customers as those of the large network. A ... various aspects of the offered services motivates the production of services with different qualities of service. These differing services can be realized by dividing a network into subnetworks with ... him for his loss of income when he peers with another network. Of course it is very difficult to determine this charge. In practice, it is often made a function of the access speed of the connection

Ngày tải lên: 14/08/2014, 12:20

... a loss of social welfare, a loss of seller’s revenue and, worst of all, a loss of the seller’s creditability in the market (since a bidder may be awarded a piece of bandwidth that is of no value ... Dependent pricing of network services IEEE/ACM Transactions on Networking 8(2), 171–184 Paschalidis, I C and J N Tsitsiklis (2000b) Congestion-dependent pricing of network services IEEE/ACM ... IEEE/ACM Transactions on Networking 8(2),... Internet interconnection and the of- net-cost pricing principle Proceedings of IDEI Conference on the Economics of the Software and Internet

Ngày tải lên: 14/08/2014, 12:20

... either of these sets of data, the statisticians would need to take account of other factors that affect attendance— weather, population, size of collection, and so forth—to isolate the effect of ... of a good is said to be elastic if the quantity supplied Percentage change in quantity demanded of good 1 Percentage change in the price of good 2 cross-price elasticity of demand a measure of ... price of the good times the quantity of the good sold. We can show total revenue graphically, as in Figure 5-2. The height of the box under the demand curve is P, and the width is Q. The area of

Ngày tải lên: 15/12/2013, 11:15

... the value of the unit of account falls by half. A similar change would occur if the gov- ernment were to reduce the length of the yard from 36 to 18 inches: As a result of the new unit of measurement, ... velocity of money, we divide the nominal value of output (nominal GDP) by the quantity of money. If P is the price level (the GDP deflator), Y the quantity of output (real GDP), and M the quantity of ... quantity of money (M) times the velocity of money (V) equals the price of output (P) times the amount of output (Y). It is called the quantity equation because it relates the quantity of money

Ngày tải lên: 15/12/2013, 11:15

... the property of a resource allocation of maximizing the total surplus received by all members of society equity the fairness of the distribution of well-being among the members of society 154 ... the producer surplus of all sellers. Quantity of Houses Painted Quantity of Houses Painted Price of House Painting 500 800 $900 0 Supply 600 1234 (b) Price = $800 Price of House Painting 500 ... composed of two parts. First, those buy- ers who were already buying Q 1 of the good at the higher price P 1 are better off be- cause they now pay less. The increase in consumer surplus of existing

Ngày tải lên: 24/12/2013, 17:15

... THE COSTS OF TAXATION 167 Let’s consider first how the elasticity of supply affects the size of the dead- weight loss. In the top two panels of Figure 8-5, the demand curve and the size of the tax ... Quantity Price 0 Quantity Size of tax Size of tax Demand Supply Demand Demand Supply Supply Size of tax Size of tax When supply is relatively inelastic, the deadweight loss of a tax is small. When supply ... result of a triangle depends on the square of its size. If we double the size of a tax, for instance, the base and height of the triangle double, so the deadweight loss rises by a factor of 4.

Ngày tải lên: 24/12/2013, 17:15

... an exporter of a good, domestic producers of the good are better off, and domestic consumers of the good are worse off. Price of Steel Price before trade Price after trade 0 Quantity of Steel Domestic ... importer of a good, domestic consumers of the good are better off, and domestic producers of the good are worse off. ◆ Trade raises the economic well-being of a nation in the sense that the gains of ... the losses of the losers. Now that we have completed our analysis of trade, we can better understand one of the Ten Principles of Economics in Chapter 1: Trade can make everyone better off. If Isoland

Ngày tải lên: 24/12/2013, 17:15

... good are better off, and consumers of the good are worse off. When a country allows trade and becomes an importer of a good, consumers are better off, and producers are worse off. In both cases, ... FOUR THE ECONOMICS OF THE PUBLIC SECTOR Markets do many things well, but they do not do everything well. In this chap- ter we begin our study of another of the Ten Principles of Economics: Governments ... consumer of the last unit of aluminum bought. Similarly, the supply curve reflects the costs of producing aluminum. At any given quantity, the height of the supply curve shows the cost of the marginal

Ngày tải lên: 24/12/2013, 17:15

... to the system before change strikes. A plan is needed for testing new versions of software. Package systems for software make this process easier, since one can allow several versions of software to ... which replace many of the older Unix equivalents, like ls and cp. GNU software has its own system of installation and set of standards. GNU will also eventually become an operating system in its own right. ... 4 Not all systems distinguish between target and device. On many systems you will find only t or d but not both. 4.6 Installation of the operating system The installation process is one of the most...

Ngày tải lên: 13/08/2014, 22:21

... There are two types of Windows system with separate software licenses: workstations and servers.Windowscanworkasastand-alonesystemorasaworkstation, integrated into a system of network services. ... mach. Knowing the operating system of a host is not sufficient. We also need to know what kind of resources the host has to offer the network, so that we can later plan 60 CHAPTER 2. SYSTEM COMPONENTS Net ... (255.255.255.0) 72 CHAPTER 2. SYSTEM COMPONENTS 3. What effect does temperature have on computer systems? 4. What is the function of an operating system? (Hint: how do you define an operating system? ) 5. Why...

Ngày tải lên: 13/08/2014, 22:21

... build software systems which apply certain principles to the problem of management. Network management has, to some extent, been likened to the process of software develop- ment in the System ... competing system to SNMP called COPS-PR [101]. 6.3. NETWORK ADMINISTRATION MODELS 207 6.3 Network administration models The management of clusters of systems leads to the concept of logistic networks. Here ... territory of more intelligent agent systems like cfengine and PIKT. Despite the shortcomings of SNMP for host operations, many operating systems do define their own MIBs for the collection of system...

Ngày tải lên: 13/08/2014, 22:21