ccna sample exam questions

ccna sample exam questions.SubnettingYou must be proficient in subnetting, be able to distinguish invalid subnet masks, and be able to calculate the number of subnets and the number of host addresses per subnet based on the subnet mask (regardless of whether the subnet mask is expressed in dotted decimal format or network bits). For point-to-point links, 255.255.255.252 is a good subnet mask because it gives the subnet two host addresses. In exam questions about subnets, it is common to indicate whether subnet 0 is available, but if this is not indicated, you will need to determine how to answer the question by looking closely at the answer, which seems unfair to me.IP address planningOn the exam, there may be simulated questions that require you to configure one or more routers and design a reasonable IP addressing scheme. Such questions will indicate how many devices each segment will contain, and you will easily know the number of segments based on the network schematic. The test will also indicate the network number assigned to you, and you will need to select the appropriate subnet mask, subnet, assign subnets to each segment, and assign host addresses in the appropriate subnets to the router interfaces. With this in mind, be sure to practice the six steps described in this section over and over until you are familiar with subnetting.Determining the Type of IP AddressYou may have been asked to select a network address, a host address, or a directed broadcast address from a list of addresses. This means that you will need to make the address type determination several times to select the correct answer. Keep in mind the trick that immediately eliminates incorrect answers: network addresses are all even, directed broadcast addresses are all odd, and host addresses can be either odd or even.6.5 Authentication SummaryIP addresses are 32 bits long, divided into 4 bytes, with adjacent bytes separated by periods. This format is known as dotted decimal representation.The five classes of IP addresses and their first byte take the following range of values: class A (1-126).Class B (128 ~191), class C (192.223), class D ( 224.239), and Class E (240 ~ 254).The network portion of a Class A address is 1 byte and the host portion is 3 bytes; the network portion of a Class B address is 2 bytes and the host portion is 2 bytes; and the network portion of a Class C address is 3 bytes and the host portion is 1 byte. Private IP includes network 10.0.0.0/8, 172.16.0.0/16 ~ 172.31.0.0/16 and 192.168.0.0/24 ~ 192.168.255.0/24.There are three types of IP addresses in a network: network addresses, host addresses, and directed broadcast addresses. The first address in the network is the network address (line number) and the last address is the broadcast address; all addresses between the network address and the broadcast address are host addresses. It is the context provided by the subnet mask that determines whether an address is a network address, a host address, or a broadcast address; the subnet mask is used to identify the boundary between the network portion and the host portion.