harrison valetski

1.5  Identify common TCP and UDP default ports As I mentioned, the Transport layer of the TCP/IP protocol suite contains two primary protocols:  TCP  and  UDP . There are many protocols, most at the Application layer, that use one or the other, or even both, of these protocols as they work their way down the OSI model. The independent sessions that are created are possible because of a logical connection called a port . If people performed only one task at a time with each computer, there might not be a need for ports, but we all know that computers can perform many tasks at one time. Because this is the case, you need a way to identify packets so that they will be processed by the computer in the correct manner. By identifying each packet with a port number, the system assures that the computer will direct the packet to the right area within it where the appropriate processes can be performed. TCP and UDP port numbers are used to identify packets in regard to...

1.4  Explain the purpose and properties of routing and switching Today's networks are not “your father's network.” Networks continue to evolve, and what we want to do on them continues to evolve. We are placing very fast computers on our networks now and expecting to receive reports, email, chat, music, videos, games, and so forth—often all at once! Because of these challenges, network administrators have to rely on newer and better technologies to both control traffic and to provide security for a network. However, the two major components that we use for our network are the same two that we used many years ago, namely, routers and switches. In this section, I will discuss the many protocols that have evolved over time that control and enhance our use of these two main components. EIGRP Enhanced Interior Gateway Routing Protocol (EIGRP)  is a Cisco proprietary protocol that combines the ease of configuration of distance vector routing protocols such as RIP or RIPv2 (d...

1.3  Explain the  purpose and properties of IP addressing IP addresses are the logical addresses that are assigned to each host on a TCP/IP network. A host is generally defined as a NIC or a router interface to which an address is assigned. Basically then, a host is anything with an IP address. By assuring that IP addresses are kept unique within a network, effective communication can be maintained. There are many classes of IP addresses, but some do not fit into a defined class and others that do are reserved for special purposes. In this section, I will discuss the many forms of IP addressing and how they relate to your network. Classes of addresses An IPv4 address is a 32-bit binary address represented in what we call  dotted decimal format . The following is an example of an IPv4 address: 192.168.1.1 In addition to the IP address, a subnet mask is also used with IPv4, which has the effect of “measuring” the address to determine which part of it is the n...