cisco ccna 4 final exam

cisco ccna 4 final exam.. More difficult to troubleshoot .. Address translation is not supported by all applications.Address translation modifies the contents of the packet (and possibly the data segment header) and recalculates the checksum if necessary, so additional processing is required for each packet, which obviously affects the throughput and speed of the connection. The more packets that need to be converted in a packet that passes through an address translation device, the greater the likelihood that the user will perceive a delay. Therefore, it is critical to choose the right address translation device.Exam Points Please keep in mind the disadvantages and limitations of address translation oTroubleshooting is more difficult when a connection has a fault related to address translation. o When troubleshooting, it is more difficult to track the actual source and destination addresses of the connection - you must log into the address translation device and look at its translation table. This can be a headache if packets have been converted multiple times at the source and destination sites. In addition, address translation has the advantage of hiding the internal addressing scheme, but this also presents a security problem - making it easier for external hackers to hide their identity: by having packets pass through one or more translation devices, thus hiding their IP address.Not all applications support address translation, which is probably the most problematic aspect of address translation. For example, some applications (such as FTP) embed IP address or port information in the data payload and require the destination device to use the payload(rather than the packet header and data segment header). This can cause problems with address translation, which by default does not translate payload information, but only header information. The best known applications that embed addressing information in the data payload are multimedia and NetBIOS applications. Some vendors' address translation devices are able to detect this practice in some applications and create the correct translation entries in the translation table; for example, Cisco routers using the IOS firewall feature set and ASA security appliances can handle numerous application issues, including embedded addressing information. However, if your product does not provide this capability, you must disable address translation on the affected devices.Authentication 1=1 Label 22.0322.3 Configuring Address TranslationThe configuration of all address translation (such as NAT and PAT) types is similar, and the following describes how to configure and verify some of the address translation types discussed earlier.