NT 2640 Final Study Guide
1. Straight-through cable (39-40): connects the wire at pin 1 on one end of the cable to pin 1 at the other end of the cable; the wire at pin 2 needs to connect to pin 2 on the other end of the cable; pin 3 on one end connects to pin 3 on the other; and so on. (To create a straight-through cable, both ends of the cable use the same TIA pinout standard on each end of the cable.)
Crossover cable: a cable that swaps the wire pairs inside the cable
2. Collision domain (43): the set of devices whose frames could collide; switches increase the size and number of collision domains
3. IPv4 Header Fields (98)
Version: Version of the IP protocol. Most networks use version 4 today.
TTL: Time to live. A value used to prevent routing loops.
Header Checksum: A value used to store an FCS value, whose purpose is to determine if any bit errors occurred in the IP header.
Source IP address: The 32-bit IP address of the sender of the packet.
Destination IP address: The 32-bit IP address of the intended recipient of the packet.
4. Passive-interface (342): stops the sending of RIP updates on the interface
5. Classless and Classful Routing (454): For a routing protocol to support VLSM, the routing protocol must advertise not only the subnet number but also the subnet mask when advertising routes. Additionally, a routing protocol must include subnet masks in its routing updates to support manual route summarization.
6. Overlapping VLSM Subnets (455): The subnets chosen to be used in any IP internetwork design must not overlap their address ranges. With a single subnet mask in a network, the overlaps are somewhat obvious; however, with VLSM, the overlapping subnets might not be as obvious. When multiple subnets overlap, a router’s routing table entries overlap. As a result, routing becomes unpredictable, and some hosts can be reached from only particular parts of the internetwork. In short, a design that uses overlapping subnets is considered to be an incorrect design, and should not
Crossover cable: a cable that swaps the wire pairs inside the cable
2. Collision domain (43): the set of devices whose frames could collide; switches increase the size and number of collision domains
3. IPv4 Header Fields (98)
Version: Version of the IP protocol. Most networks use version 4 today.
TTL: Time to live. A value used to prevent routing loops.
Header Checksum: A value used to store an FCS value, whose purpose is to determine if any bit errors occurred in the IP header.
Source IP address: The 32-bit IP address of the sender of the packet.
Destination IP address: The 32-bit IP address of the intended recipient of the packet.
4. Passive-interface (342): stops the sending of RIP updates on the interface
5. Classless and Classful Routing (454): For a routing protocol to support VLSM, the routing protocol must advertise not only the subnet number but also the subnet mask when advertising routes. Additionally, a routing protocol must include subnet masks in its routing updates to support manual route summarization.
6. Overlapping VLSM Subnets (455): The subnets chosen to be used in any IP internetwork design must not overlap their address ranges. With a single subnet mask in a network, the overlaps are somewhat obvious; however, with VLSM, the overlapping subnets might not be as obvious. When multiple subnets overlap, a router’s routing table entries overlap. As a result, routing becomes unpredictable, and some hosts can be reached from only particular parts of the internetwork. In short, a design that uses overlapping subnets is considered to be an incorrect design, and should not