Author: examcert

Network Layer Summary (22.4) The following is a summary of each topic in the chapter and some questions for your reflection. What Did I Learn in this Module? (22.4.1) • Network Layer Characteristics—The network layer, or OSI Layer 3, provides services to allow end devices to exchange data across networks. IPv4 and IPv6 are the…

IPv6 Packet Header (22.3.4) The fields for the IPv6 packet header shown in Figure 22-10 are as follows: • Version —This field contains a 4-bit binary value set to 0110 that identifies this as an IP version 6 packet. • Traffic Class — This 8-bit field is equivalent to the IPv4 Differentiated Services (DS) field….

IPv6 Packet (22.3) This topic introduces the successor of IPv4: IPv6. Limitations of IPv4 (22.3.1) IPv4 is still in use today. This topic is about IPv6, which will eventually replace IPv4. To better understand why you need to know the IPv6 protocol, it helps to know the limitations of IPv4 and the advantages of IPv6….

IPv4 Packet Header Fields (22.2.2) The binary values of each field identify various settings of the IP packet. Protocol header diagrams, which are read left to right, and top down, provide a visual to refer to when discussing protocol fields. The IP protocol header diagram in Figure 22-7 identifies the fields of an IPv4 packet….

Media Independent (22.1.7) Unreliable means that IP does not have the capability to manage and recover from undelivered or corrupt packets. This is because while IP packets are sent with information about the location of delivery, they do not contain information that can be processed to inform the sender whether delivery was successful. Packets may…

IP Encapsulation (22.1.3) IP encapsulates the transport layer (the layer just above the network layer) segment or other data by adding an IP header. The IP header is used to deliver the packet to the destination host. Figure 22-2 illustrates how the transport layer PDU is encapsulated by the network layer PDU to create an…

Objectives Upon completion of this chapter, you will be able to answer the following questions: • How does the network layer use IP protocols for reliable communications? • What is the role of the major header fields in the IPv4 packet? • What is the role of the major header fields in the IPv6 packet?…

Ethernet Switching Summary (21.5) The following is a summary of each topic in the chapter and some questions for your reflection. What Did I Learn in this Module? (21.5.1) • Ethernet—There is no official local area networking standard protocol, but over time, one technology, Ethernet, has become more common than the others. Ethernet protocols define…

Find the Destination MAC Address If the destination MAC address is a unicast address, the switch will look for a match between the destination MAC address of the frame and an entry in its MAC address table. If the destination MAC address is in the table, it will forward the frame out the specified port….

The MAC Address Table (21.4) Compared to legacy Ethernet hubs, Ethernet switches improve efficiency and overall network performance. Although traditionally most LAN switches operate at Layer 2 of the OSI model, an increasing number of Layer 3 switches are now being implemented. This section focuses on Layer 2 switches. Layer 3 switches are beyond the…