NAD-chapter5-6.pdf

文档介绍：Chapter 5: Tunneling and Application Gateway Chapter 5: Tunneling and Application Gateway
Chapter goal: Chapter goal:
„ Multiprotocol environment „ Multiprotocol environment
„ work technologies „ work technologies
„ Encapsulation and tunneling „ Encapsulation and tunneling
„ Clients and servers in constrained „ Clients and servers in constrained
environments environments
„ Application gateways „ Application gateways
„ Application gateway examples „ Application gateway examples
哈工大计算机学院 work Application Development Tunneling and Application Gateway 1 哈工大计算机学院 work Application Development Tunneling and Application Gateway 2
Multiprotocol environment Multiprotocol environment
„
Not all machines plete TCP/IP Hosts using TCP/IP Hosts using TCP/IP
support
……
„ Not anizations use TCP/IP exclusively
to puters.
1 2
„ Most anizations have several
Wide area
groups of machines, with group using its work
protocol suite, because: Hosts using ATM that uses Hosts using ATM
„ Networking has evolved slowly ATM
„ Vendors promoted work systems
„ TCP/IP not always available „ Chief disadvantages:
„ Minimize expense
„ Duplication of effort
„ User habits
„ Limitations of interoperability
哈工大计算机学院 work Application Development Tunneling and Application Gateway 3 哈工大计算机学院 work Application Development Tunneling and Application Gateway 4
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