The Illustrated Network- P26 ppt
The Illustrated Network- P26 ppt
... when the IP address prefi x is the same on the destination and on the source. In this case, the MAC addresses on the frame that leave the source and the ones in the frame that arrive at the destination ... segment Ethernet LANs, the Ethernet frame that leaves a source may or may not be the same frame that arrives at the destination. If the source and destination...
Ngày tải lên: 04/07/2014, 07:20
The Illustrated Network- P16 ppt
... as long as the IP address (32 bits in the case of IPv4). If the mask bit is a 1 bit, the correspond- ing bit in the IP address is part of the network portion of the IP address. If the address ... that form the Internet: by the network portion of the IP address. The whole IP address specifi es the host on the network, and the network portion identifi es the LAN....
Ngày tải lên: 04/07/2014, 07:20
The Illustrated Network- P24 ppt
... 1 in the three packet set, so the fi rst router along the path should generate an ICMP Time Exceeded message to the sender. The round-trip delay in the timestamp fi eld and IP address of the router ... recorded by the sender and another set of packets is sent, this time with the TTL set to 2. These packets are discarded by the second router, and another ICMP message is s...
Ngày tải lên: 04/07/2014, 07:20
The Illustrated Network- P25 ppt
... at the role of the service- provider routers in the chapters on routing protocols. For now, we’ll focus on how sending devices decide whether the destination is on their own network or whether ... to the source when the packet is big- ger than the MTU for the next-hop link. The next-hop link’s MTU size is reported in the message. In ICMPv4, this type of information was...
Ngày tải lên: 04/07/2014, 07:20
The Illustrated Network- P30 ppt
... Datagram Protocol 263 The DF bit in the packet is set, and the UDP checksum fi eld is used. Technically, the UDP checksum is optional, and the client decides whether to use it. The server responds ... hosts on the network to explore UDP. 260 PART II Core Protocols At the receiver, the value of the Checksum is copied and the fi eld again set to zero. The checksum is aga...
Ngày tải lên: 04/07/2014, 07:20
The Illustrated Network- P33 pptx
... congested (they are the fi rst to know), so they can easily fl ip some bits in the IPv4 and IPv6 headers of the packets they route. These bits are in the TOS (IPv4) and Flow (IPv6) fi elds, and the hosts ... 11.3, the client chooses an initial sequence number (ISN) in the fi rst SYN sent to the server. The server ACKs the ISN by adding one to the proposed ISN (ACKs alway...
Ngày tải lên: 04/07/2014, 07:20
The Illustrated Network- P35 pptx
... (DOS). Sockets for Windows The pressure that led to the development of the WinSock interface is simple to relate. Users wanted to hook their Windows-based PCs into the Internet. The Internet only understands ... as the Unix operating system handles that. With Windows applications written for the WinSock DLL, all of the TCP/IP processes worried about the decision of whethe...
Ngày tải lên: 04/07/2014, 07:20
The Illustrated Network- P44 pptx
... portion of the Ethereal capture of the packet stream, detailing the UDP con- tent inside the IP packet. FIGURE 16.2 Multicast packet capture, showing the MAC address format used and the port in the ... indicates the number of bits that is signifi cant in the following prefi x. There is no length fi eld for this list that ends the Update message. The number of NLRIs presen...
Ngày tải lên: 04/07/2014, 08:20
The Illustrated Network- P54 pptx
... contrast to the text fi les used in most Unix DNS versions (as shown in Figure 19.4). The Ethereal capture in Figure 19.5 shows the utter simplicity of the DNS message exchanges. There’s even ... "named.local"; }; The two zone statements only point to the root servers on the Internet (in the hints fi le named.ca) and make this server the master for its own loopba...
Ngày tải lên: 04/07/2014, 08:20
The Illustrated Network- P62 ppt
... and there. In this chapter, we explore the SSL, the most widely deployed security protocol on the Web (and in the world) today. Many users notice the little yellow lock that appears in the ... brand new to the server. Stateless servers are the easiest to operate. If they fail, just start them up again. No one cares where they left off. You can even transfer processing to an...
Ngày tải lên: 04/07/2014, 08:20