Đang chuẩn bị liên kết để tải về tài liệu:
BUILDING REMOTE ACCESS NETWORKS phần 9

Bất kỳ thiết lập thời gian chờ hoặc chủ yếu thực hiện ở đây cho máy chủ cụ thể sẽ ghi đè lên bất kỳ cài đặt toàn cầu cho các giá trị này.Chọn một liên kết trang web (bạn có thể thay đổi sau này, nếu bạn cần). 5. Nhấn OK. 6. Kích chuột phải vào Subnets. 7. | Chapter 11 Private Addressing and Subnetting Large Networks Solutions in this chapter Discovering the motivation for using private addresses Calculating address allocation efficiency Examining RFC 1918 private address ranges Developing strategies for subnetting private addresses 457 458 Chapter 11 Private Addressing and Subnetting Large Networks Introduction You ve heard it said We re running out of IP Addresses Really In the IP version 4 architecture we use 32-bit address fields. With 32-bits in our addresses there are 232 unique addresses available. That s over four billion addresses. We know that the Internet has experienced exponential growth over the last few years but even with continued growth it s unlikely that we ll see anywhere near four billion machines on the Internet any time soon. So where s the problem The problem exists in the granularity of address allocation. Prior to Classless Inter-Domain Routing CIDR addresses were allocated in classful blocks. That is if you needed more addresses than a Class C network provided you got a Class B network address if you needed more than a Class B provided you got a Class A network address. Those were the only three choices. Not many organizations actually got Class A addresses of course. Although there are indeed over 4 billion unique IP addresses available with the current version of IP the number of unique network numbers is much fewer. In fact there are only 126 Class A networks about 16 000 Class B networks and about 2 million Class C networks. This design has led to widespread waste of globally unique IP addresses. Strategies to Conserve Addresses In the 1970s the architects of the Internet envisioned an internetwork with dozens of networks and hundreds of nodes. They developed a design where any node on the internetwork was reachable by any other node. Back then no one could have guessed the effect new applications like the World Wide Web and vastly increased bandwidth would have on the number of people .