10 Networking and the Internet in .NET Creation GTIN-13 in .NET 10 Networking and the Internet

How to generate, print barcode using .NET, Java sdk library control with example project source code free download:
384 10 Networking and the Internet using visual .net topaint ean13+5 on web,windows application Microsoft Windows SDK bits (100) EAN-13 Supplement 2 for .NET , 21 netid bits (2 million networks), and 8 hostid bits (254 hosts). Today a new large customer will not receive a class A or B network but is likely to receive a class C or several (usually contiguous) class C networks, if merited.

Several other classes of networks exist. Class D networks are reserved for multicast (page 1161) networks. When you run netstat nr on a Linux system, you can see whether the machine is a member of a multicast network.

A 224.0.0.

0 in the Destination column that netstat displays indicates a class D, multicast address (Table 10-2). A multicast is like a broadcast, but only hosts that subscribe to the multicast group receive the message. To use Web terminology, a broadcast is like a push.

A host pushes a broadcast on the network, and every host on the network must check each packet to see whether it contains relevant data. A multicast is like a pull. A host will see a multicast only if it registers itself as subscribed to a multicast group or service and pulls the appropriate packets from the network.

. Table 10-3. Computatio .net vs 2010 GTIN-13 ns for IP address 131.204.

027.027 ---------------Class B----------131 .204 CC 1100 1100 .

255 FF 1111 1111 1100 1100 1111 1111 1100 1100 .204 CC 1100 1100 .204 CC 1100 1100.

netid .027 1B 00 ean13+5 for .NET 01 1011 .

255 FF 1111 1111 0001 1011 1111 1111 0001 1011 .027 1B 0001 1011 .27 1B 0001 1011 .

hostid .027 decim ean13+5 for .NET al 1B hexadecimal 0001 1011 binary .

000 decimal 00 hexadecimal 0000 0000 binary 0001 1011 0000 0000 binary 0000 0000 .000 decimal 00 hexadecimal 0000 0000 binary .255 decimal FF hexadecimal 1111 1111 binary.

IP address 83 1000 0011 255. Subnet mask FF 1111 1111 IP address bitwise AND Subnet mask = Subnet number 1000 0011 EAN/UCC-13 for .NET 1111 1111 1000 0011 131. Subnet number 83 1000 0011 131. Broadcast address (set host bits to 1). 83 1000 0011. Table 10-3 shows some of the computations for the IP address 131.204.027.

027. Each address is shown in decimal, hexadecimal, and binary form. Binary is the easiest to work with for bitwise (binary) computations.

The first three lines show the IP address. The next three lines show the subnet mask (page 1175) in three bases. Next the IP address and the subnet mask are ANDed together bitwise to yield the subnet number (page 1175), which is shown in three bases.

The last three lines. Types of Networks and How They Work show the b roadcast address (page 1138), which is computed by taking the subnet number and turning the hostid bits to 1s. The subnet number identifies the local network. The subnet number and the subnet mask determine what range the IP address of the machine must be in.

They are also used by routers to segment traffic; see network segment (page 1162). A broadcast on this network goes to all hosts in the range 131.204.

27.1 through 131.204.

27.254 but will be acted on only by hosts that have a use for it..

Subnets Each host on a network must process each broadcast packet to determine whether the information in the packet is useful to that host. If the network includes numerous hosts, each host must process many packets. To maintain efficiency most networks and particularly shared media networks such as Ethernet need to be split into subnetworks, or subnets.

9 The more hosts on a network, the more dramatically network performance is affected. Organizations use router and switch technology called VLANs (virtual local area networks) to group similar hosts into broadcast domains (subnets) based on function. For example, it is not uncommon to see a switch with different ports being part of different subnets.

See page 462 for information on how to specify a subnet.. Subnet mask A subnet m ask (or address mask) is a bit mask that identifies which parts of an IP address correspond to the network address and the subnet portion of the address. This mask has 1s in positions corresponding to the network and subnet numbers and 0s in the host number positions. When you perform a bitwise AND on an IP address and a subnet mask (Table 10-3), the resulting address contains everything except the host address (hostid) portion.

There are several ways to represent a subnet mask: A network could have a subnet mask of 255.255.255.

0 (decimal), FFFFFF00 (hexadecimal), or /24 (the number of bits used for the subnet mask). If it were a class B network (of which 16 bits are already fixed), this yields 28 (24 total bits 16 fixed bits = 8 bits, 28 = 256) networks10 with 28 2 (256 2 = 254) hosts11 on each network. For example, when you divide the class C address 192.

25.4.0 into eight subnets, you get a subnet mask of 255.

255.255.224, FFFFFFE0, or /27 (27 1s).

The eight resultant networks are 192.25.4.

0, 192.25.4.

32, 192.25.4.

64, 192.25.4.

96, 192.25.4.

128, 192.25.4.

160, 192.25.4.

192, and 192.25.4.

224. You can use a Web-based subnet mask calculator to calculate subnet masks (refer to Network Calculators on page 1105). To use this calculator to determine the preceding subnet mask, start with an IP host address of 192.


For more information refer to Specifying a Subnet on page 462.. 9. Splitti EAN13 for .NET ng a network is also an issue with other protocols, particularly AppleTalk.

10. The first and last networks are reserved in a manner similar to the first and last hosts, although the standard is flexible. You can configure routers to reclaim the first and last networks in a subnet.

Different routers have different techniques for reclaiming these networks. 11. Subtract 2 because the first and last host addresses on every network are reserved.

Copyright © . All rights reserved.