ccna 200-301 free videos

ccna 200-301 free videos.. Running-config: A file that stores the configuration commands that the router IOS is currently running. All but a few of the configuration commands on the router are stored in the running-config file, called the running-config.. IPRoutingTable: Stores information about directly connected and remote networks and is used to determine the best path for packet forwarding.. ARP Cache:Caches the mapping of IPv4 to MAC addresses, similar to the ARP cache on a computer, which reduces the number of address resolution messages and improves communication on the LAN connected to the router. ARP cache is used on the router's LAN interfaces, such as Ethernet interfaces; there are no MAC addresses on serial WAN interfaces, and ARP cache is not used.. PacketBuffer:When a packet is received by the interface or when a packet leaves the interface, the packet is temporarily stored in ain the buffer. When the device is powered off or rebooted, the contents of the RAM are lost.NonVolatile RAM (NVRAM) NVRAM retains its contents even when power is lost. The router uses NVRAM to store the startup-config, and all changes to the configuration file are stored in the running-config in the RAM and take effect immediately. If you want the changes to work even after the router is powered off or rebooted, you need to save the running-config file, that is, save the changes to the startup-config file.The changes are saved to the startup configuration file. The contents of the NVRAM will not be lost after the device is powered off or rebooted.The I/O port is the port through which packets enter and exit the router (in many places in this book, ports are also referred to as interfaces.The ports and interfaces refer to the same thing, only the customary terminology is a little different). Each I/O port is connected to a specific media converter, which provides a variety of specific media, such as Ethernet, Token Ring LAN, RS-232, or V.35 WAN.8 hush refinement chapter 4 cisco router** i04 ______________ _______M___ area network provides the physical translation interface. In Cisco terminology, various router features such as routing protocol updates and access control lists are associated with an interface. You can use the showinterface" command to display information related to all interfaces in the router.