qr code c# tutorial 20: OSPF Routing in Objective-C

Encode QR Code JIS X 0510 in Objective-C 20: OSPF Routing

20: OSPF Routing
Denso QR Bar Code Generation In Objective-C
Using Barcode generation for iPhone Control to generate, create QR Code image in iPhone applications.
Barcode Maker In Objective-C
Using Barcode generation for iPhone Control to generate, create bar code image in iPhone applications.
FIGURE 20-3
QR-Code Creation In Visual C#.NET
Using Barcode creation for .NET framework Control to generate, create QR-Code image in .NET applications.
QR-Code Generator In Visual Studio .NET
Using Barcode drawer for ASP.NET Control to generate, create QR Code JIS X 0510 image in ASP.NET applications.
LSA update process
Encoding QR-Code In VS .NET
Using Barcode generation for .NET Control to generate, create QR-Code image in .NET applications.
QR Maker In Visual Basic .NET
Using Barcode encoder for VS .NET Control to generate, create QR Code ISO/IEC18004 image in .NET applications.
Note that the communications between OSPF routers is connection-oriented, even though multicasts are used For example, if a router tells a DR about a change, the DR acknowledges this new piece of information with the source of the communication Likewise, when the DR shares this information with the other routers on the segment, the DR expects acknowledgments from each of these neighbors Remember that when an OSPF router exchanges updates with another, the process requires an acknowledgment: this ensures that a router or routers have received the update The exception to the incremental update process is that the DR floods its database every 30 minutes to ensure that all of the routers on the segment have the most up-to-date link state information It does this with a destination address of 224005 (all OSPF routers on the segment) When building the routing table using link state information, an OSPF router can keep up to 16 paths to a destination in its routing table The only restriction is that the paths must have the same accumulated cost metric
Printing GS1-128 In Objective-C
Using Barcode creation for iPhone Control to generate, create UCC-128 image in iPhone applications.
Make DataMatrix In Objective-C
Using Barcode encoder for iPhone Control to generate, create DataMatrix image in iPhone applications.
A two-way state indicates that two OSPF routers are neighbors A full
Barcode Creation In Objective-C
Using Barcode printer for iPhone Control to generate, create bar code image in iPhone applications.
Bar Code Maker In Objective-C
Using Barcode maker for iPhone Control to generate, create bar code image in iPhone applications.
state indicates the completion of sharing of links between routers
EAN 13 Generation In Objective-C
Using Barcode creator for iPhone Control to generate, create EAN 13 image in iPhone applications.
Making Bar Code In Objective-C
Using Barcode printer for iPhone Control to generate, create bar code image in iPhone applications.
OSPF Con guration
Encoding UPC-E In Objective-C
Using Barcode generator for iPhone Control to generate, create Universal Product Code version E image in iPhone applications.
Barcode Recognizer In Visual C#
Using Barcode reader for .NET Control to read, scan read, scan image in .NET framework applications.
CERTIFICATION OBJECTIVE 2003
UPC A Decoder In Visual Studio .NET
Using Barcode scanner for .NET framework Control to read, scan read, scan image in VS .NET applications.
Encode Data Matrix 2d Barcode In .NET
Using Barcode encoder for ASP.NET Control to generate, create Data Matrix image in ASP.NET applications.
OSPF Configuration
Recognizing Bar Code In VS .NET
Using Barcode Control SDK for ASP.NET Control to generate, create, read, scan barcode image in ASP.NET applications.
USS Code 128 Generation In Java
Using Barcode generator for Java Control to generate, create Code 128 image in Java applications.
Configuring OSPF is slightly different from configuring RIP When configuring OSPF, use the following syntax:
Code 3/9 Printer In VB.NET
Using Barcode generator for VS .NET Control to generate, create USS Code 39 image in .NET framework applications.
UPC - 13 Reader In C#.NET
Using Barcode decoder for .NET Control to read, scan read, scan image in .NET applications.
Router(config)# router ospf process_ID Router(config-router)# network IP_address wildcard_mask area area_#
The process_ID is locally significant and is used to differentiate between OSPF processes running on the same router Your router might be a boundary router between two OSPF autonomous systems, and to differentiate them on your router, you ll give them unique process IDs Note that these numbers do not need to match between different routers and that they have nothing to do with autonomous system numbers (The process of configuring two OSPF processes on the same router is beyond the scope of this book)
When con guring the OSPF routing process, you must specify a process ID (identi er)This uniquely identi es an instance of the OSPF database on
the router and is only locally signi cant: it doesn t have to match on each router in the AS
When specifying what interfaces go into an OSPF area, use the network command As you can see in the preceding code listing, the syntax of this command is different from that of RIP s configuration, where you specify only a class address OSPF is classless With this command, you can be very specific about what interface belongs to a particular area The syntax of this command lists an IP address or network number, followed by a wildcard mask, which is different from a subnet mask A wildcard mask tells the router the interesting component of the address in other words, what part of the address it should match on This mask is also used with access lists, which are discussed thoroughly in 22 A wildcard mask is 32 bits in length A 0 in a bit position means there must be a match, and a 1 in a bit position means the router doesn t care Actually, a wildcard
20: OSPF Routing
mask is an inverted subnet mask, with the 1s and 0s switched Using a wildcard mask, you can be very specific about which interfaces belong to which areas The last part of the command tells the router to which area these addresses on the router belong
Unlike in RIP, the network statement allows you to specify an IP address and a wildcard mask, which is an inverted subnet mask You must also specify to which area this address or addresses will belong: network network_# wildcard_mask area area_# A trick
of converting a subnet mask to a wildcard mask is to subtract the subnet mask from 255255255255; the result will be the corresponding wildcard mask Examine 22 for more information, including examples, on how this is done
Let s look at some code examples to see how the wildcard mask works Use the router shown in Figure 20-4 as an illustration
Router(config)# router Router(config-router)# Router(config-router)# Router(config-router)# Router(config-router)# ospf 1 network network network network 10111 0000 area 0 10121 0000 area 0 1721611 0000 area 0 1721621 0000 area 0
In this example, the interfaces with addresses of 10111, 10121, 1721611, and 1721611 all are associated with area 0 A wildcard mask of 0000 says that there
FIGURE 20-4
1721620/24
Copyright © OnBarcode.com . All rights reserved.