Computer Networking A Top-Down Approach Featuring the Internet phần 10 doc

... filters with application gateways. Application gateways look beyond the IP/TCP/UDP headers and actually make policy decisions based on application data. An application gateway is an application-specific ... encapsulated as a standard IP datagram. For the protocol field in the IP header, the value 51 is used to indicate that the datagram includes an AH header. When the destin...

Ngày tải lên: 14/08/2014, 13:22

... is almost identical to TCPServer.java. As with TCPServer.java, we import the java.io and java.net packages. In addition to these two packages we also import the java.util package, which contains ... of the data. These retransmissions are completely transparent to the application programs. The DNS lookup is also transparent to the application programs. To test the program pair...

Ngày tải lên: 14/08/2014, 13:21

... phone application. The UDP segment is encapsulated in an IP datagram, and the IP datagram makes it way through the network towards the receiver. As the datagram wanders through the network, it passes ... TCP. Address translation is one of the more important gatekeeper services. Each terminal can have an alias address, such as the name of the person at the terminal, the...

Ngày tải lên: 14/08/2014, 13:22

... by paying more a state of affairs that some (particularly Americans!) find odd. We'll take a look at state-of -the art Internet research that is aimed at changing this situation in Chapter ... n%2 0Approach% 2 0Featuring% 2 0the% 2 0Internet/ preface.htm (1 of 4)20/11/2004 15:51:35 Instructor Overheads: Computer Networking: A Top Down Approach Featuring the Internet...

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... proach%2 0Featuring% 2 0the% 2 0Internet/ protocol_stacks.htm (6 of 7)20/11/2004 15:51:44 ATMover (AAL), the ATM Layer, and the ATM Physical Layer: ATM Adaptation Layer (AAL) ATM Layer ATM Physical Layer ... interface, AAL5 prepares IP datagrams for ATM transport; at the ATM-to-IP interface, AAL5 reassembles ATM cells into IP datagrams. Figure 1 .10- 2 shows the protocol stack fo...

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... msec. Assuming for simplicity that ACK packets are the same size as data packets and that the receiver can begin sending an ACK packet as soon as the last bit of a data packet is received, the last ... integrity of the data in the datagrams. With IP service, datagrams can overflow router buffers and never reach their destination, datagrams can arrive out of order, and bits in...

Ngày tải lên: 14/08/2014, 13:21

... to "fragment" the data in the IP datagram among two or more smaller IP datagrams, and then send these smaller datagrams over the outgoing link. Each of these smaller datagrams is referred ... data, whereas packets for many wide-area links can carry no more than 576 bytes. The maximum amount of data that a link-layer packet can carry is called the MTU (maximum transfer...

Ngày tải lên: 14/08/2014, 13:21

... forward the unicast packet to B, blissfully unaware that the unicast datagram itself contains a multicast datagram. When the unicast datagram arrives at B, B then extracts the multicast datagram. ... each of the receivers. What are the drawbacks of this approach compared to the approach that provides native multicast support at the network layer? What are the advanta...

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... make Ethernet simple and cheap. But it also means that the stream of datagrams passed to the network layer can have gaps. If there are gaps due to discarded Ethernet frames, does the application-layer ... router. ATM in the entry router indexes an ATM table to determine the VCI for the VC that leads to the ATM destination address. AAL5 then creates ATM cells out of the IP d...

Ngày tải lên: 14/08/2014, 13:21

... that: ● the sender of the data is as claimed, i.e., that the sender has signed the data and this signature can be checked ● the transmitted data has not been changed since the sender created ... provides hard, mathematical provable guarantees on the delay of each of the individual packets in a flow. The control-load service does not provide any hard guarantees, but inst...

Ngày tải lên: 14/08/2014, 13:22