Ethernet Networking- P8

Ethernet Networking- P8:One of the biggest problems when discussing networking is knowing whereto start. The subject of computer networks is one of those areas for whichyou have to "know everything to do anything." Usually, the easiest way toease into the topic is to begin with some basic networking terminology andthen look at exactly what it means when we use the word Ethernet.
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Ethernet Networking- P8198 Network Maintenance, Monitoring, and Control Figure 9-21: Opening a new TCP/IP connection from a Windows PC Figure 9-22: Opening a new TCP/IP connection from a Macintosh Note: If a Macintosh has multiple monitors, then Tim- buktu Pro shows only the start-up m o n i t o r - t h a t is, the one containing the menu bar.Remote Control 199 Figure 9-23 Opening a new AppleTalk connection Figure 9-24 A Macintosh screen in a Timbuktu Pro window on a Windows PC200 Network Maintenance, Monitoring, and Control Figure 9-25: A Windows 95 screen in a Timbuktu Pro window on a MacintoshFile Exchange Timbuktu supports two types of file exchange, which it calls sending files and exchanging files. Sending a file transfers it to a single drop fold- er on the remote computer. Exchanging files gives the remote user com- plete control over where transferred files are placed, as in Figure 9-26. The interface for exchanging files from a Windows machine is identical to the Macintosh interface.Messaging Timbuktu Pro provides two ways to exchange real-time messages. The first is through a relatively standard chat room interface, such as that in Figure 9-27. A user can add himself or herself to a chat session, or a user can add a remote computer to a chat session (assuming that the remote user has the access rights to do so).Remote Control 201 Figure 9-26: Using Timbuktu Pro to exchange files Figure 9-27: Timbuktu Pro chat If networked computers are equipped with microphones and speakers, Timbuktu Pro provides an intercom service that allows users to speak with each other (see Figure 9-28). This can be an alternative to a long-distance phone call when the remote user has dialed in to the network from some other location, perhaps using a dedicated line. (If the remote user is paying long-distance charges to connect to the network, of course there would be no savings.)202 Network Maintenance, Monitoring, and Control Figure 9-28 Establishing a Timbuktu Pro intercom session 5ecurily IssuesPeople, including yours truly, have written entire books on network secu-rity, and no single book can possibly cover the entire topic. But if you talkto professionals in businesses both large and small, their overriding con-cern today is network security. We would be horribly remiss if we didntat least try to look at the major issues facing the operator of a network ofany size and introduce you to some of the ways in which you can protectyour network.This chapter is an overview of both security threats and security fixes. Itcant provide everything you need to know, but it will alert you to thingsyou should watch and resources you should have at your fingertips. 203204 Security IssuesSecurity Threats to Home and Small Offices Is anyone really out there to get you, with your small network? Yes, they are. Well, not necessarily you in particular, but certainly the resources that your network can provide to help them with their larger attacks. You may also have content on your network that someone would want to steal. And just as important, there may be legal requirements for privacy that you must enforce. From where does the danger come? Over the Internet and from your inter- nal network. You have to be aware of dangers from both sources.Malware Malware is short for malicious software, any software that could do something nasty to your network. There are several types of malware, each of which propagates differently and has a different goal: Virus: A virus is a self-propagating piece of software that runs as an executable program on a target machine. It is not, howev- er, a stand-alone piece of software. It must piggyback on some- thing else, such as a piece of e-mail or other application program, and is installed on a victim machine when the user accesses the host software. A viruss effect can be relatively ...