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The Illustrated Network- P67

The Illustrated Network- P67:In this chapter, you will learn about the protocol stack used on the global public Internet and how these protocols have been evolving in today’s world. We’ll review some key basic defi nitions and see the network used to illustrate all of the examples in this book, as well as the packet content, the role that hosts and routers play on the network, and how graphic user and command line interfaces (GUI and CLI, respectively) both are used to interact with devices. | 629 QUESTIONS FOR READERS Figure 24.8 shows some of the concepts discussed in this chapter and can be used to answer the following questions. t Frame 14 230 bytes on wire 230 bytes captured 0 Ethernet II Src 00 05 85 88 cc db Dst 00 0e 0c 3b 8f 94 t Internet Protocol Src Addr 10.10.12.1 10.10.12.1 Dst Addr 10.10.11.177 10.10.11.177 t User Datagram Protocol Src Port snmp 161 Dst Port 1307 1307 v Simple Network Management Protocol Version 2C 1 Community public PDU type RESPONSE 2 Request Id 0x6b8b4568 Error Status NO ERROR 0 Error Index 0 Object identifier 1 1.3.6.1.2.1.1.1.0 iso.3.6.1.2.1.1.1.0 Value STRING M7i-router Object identifier 2 1.3.6.1.2.1.1.2.0 iso.3.6.1.2.1.1.2.0 Value OID iso.3.6.1.4.1.2636.1.1.1.2.10 Object identifier 3 1.3.6.1.2.1.1.3.0 iso.3.6.1.2.1.1.3.0 Value Timeticks 1209176765 139 days 22 49 27.65 Object identifier 4 1.3.6.1.2.1.1.4.0 iso.3.6.1.2.1.1.4.0 value STRING WalterG Object identifier 5 1.3.6.1.2.1.1.5.0 iso.3.6.1.2.1.1.5.0 Value STRING Router_R6 Object identifier 6 1.3.6.1.2.1.1.6.0 iso.3.6.1.2.1.1.6.0 Value Object identifier 7 1.3.6.1.2.1.1.7.0 iso.3.6.1.2.1.1.7.0 Value INTEGER 4 Object identifier 8 1.3.6.1.2.1.2.1.0 iso.3.6.1.2.1.2.1.0 Value INTEGER 50 FIGURE 24.8 Ethereal capture of an SNMP response message. Note the object identifiers. 1. Which version of SNMP is used here 2. Which router IP address and port are responding 3. Express the SMI tree to the sysDescr group in English instead of numbers. It starts with iso.org. 4. The actual time ticks value of 1209176765 is interpreted. What does this value represent 5. Where is the response telling the management application to go for more device-specific information PART Security VI Security is a major concern in networking today. This part of the book continues the theme begun with SSL and explores the basic aspects of security used on the Internet today. Chapter 25 Secure Shell Remote Access Chapter 26 MPLS-Based Virtual Private Networks Chapter 27 Network Address Translation Chapter