Broadcasts, Packet header types | Netopia R3100 instruction

E-12 User’s Reference Guide

The following diagram illustrates the IP address space taken up by the two remote IP subnets. You can see from the diagram why the term nested is appropriate for describing these subnets.

valid addresses used by a.b.c.128

valid addresses used by a.b.c.248

1

129

190

249

254

Address range available to a.b.c.0, less the two nested subnets

Broadcasts

As mentioned earlier, binary IP host or subnet addresses composed entirely of ones or zeros are reserved for broadcasting. A broadcast packet is a packet that is to be delivered to every host on the network, if both the host address and the subnet address are all ones or all zeros, or to every host on the subnetwork, if the host address is all ones or all zeros but the subnet address is a combination or zeros and ones. Instead of making many copies of the packet, individually addressed to different hosts, all the host machines know to pay attention to broadcast packets, as well as to packets addressed to their speciﬁc individual host addresses. Depending on the age and type of IP equipment you use, broadcasts will be addressed using either all zeros or all ones, but not both. If your network requires zeros broadcasting, you must conﬁgure this through SNMP.

Packet header types

As previously mentioned, IP works with other protocols to allow communication over IP networks. When IP is used on an Ethernet network, IP works with the Ethernet or 802.3 framing standards, among other protocols. These two protocols specify two different ways to organize the very ﬁrst signals in the sequence of electrical signals that make up an IP packet travelling over Ethernet. By default, the Netopia R3100 uses Ethernet packet headers for IP trafﬁc. If your network requires 802.3 IP framing, you must conﬁgure this through SNMP.

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Netopia R3100 manual Broadcasts, Packet header types

Contents

Netopia R3100 Isdn Routers Part Number Contents Ii User’s Reference Guide Part II Advanced Configuration Iv User’s Reference Guide Aurp Vi User’s Reference Guide Part III Appendixes Viii User’s Reference Guide Contents User’s Reference Guide Conﬁguration options for your Netopia R3100 Isdn Router Small Ofﬁce connection to the Internet Small Ofﬁce connection to the Internet Direct Connection to a Corporate Ofﬁce Telecommuter Conﬁgured to accept incoming dial-up connections Conﬁgured for Idsl Part I Getting Started User’s Reference Guide Overview Features and capabilitiesChapter Introduction Introduction How to use this guide What you need Chapter Making the Physical ConnectionsFind a location Making the Physical Connections Identify the connectors and attach the cables Netopia R3100 Isdn Router Back Panel Ports Cable to your router on Services on Netopia R3100 Isdn Router Status Lights Netopia R3100 LED front panel Chapter Setting up your Router with the SmartStart Wizard Setting up your Router with the SmartStart Wizard Before running SmartStart Setting up your Router with the SmartStart Wizard SmartStart Wizard conﬁguration screens Easy or Advanced setup Easy option Setting up your Router with the SmartStart Wizard User’s Reference Guide Setting up your Router with the SmartStart Wizard User’s Reference Guide Advanced option Connection Proﬁle screen on Dynamic conﬁguration recommended Conﬁguration tab Static conﬁguration optional Add. Repeat this process for the secondary DNS Conﬁguring TCP/IP on Macintosh computers TCP/IP TCP/IP or MacTCP Dynamic conﬁguration using MacIP optional Setting up your Router with the SmartStart Wizard User’s Reference Guide Chapter Connecting Your Local Area Network Connecting Your Local Area Network Readying computers on your local network Connecting to an Ethernet network 10Base-T 10BASE-T Remote console Connecting to a LocalTalk network Wiring guidelines for PhoneNET cabling User’s Reference Guide SmartView Chapter SmartViewSmartView overview Navigating SmartView General Machine information Connection Proﬁles Event history pages Device Event History WAN Event History Standard Html web-based monitoring pages User’s Reference Guide Console-based Management Chapter Console-based ManagementAbout Console-based Management Connecting through a Telnet session Connecting a local terminal console cable to your router Conﬁguring Telnet software PC ANSI-BBS Navigating through the console screens User’s Reference Guide How to access the Easy Setup console screens Chapter Easy SetupEasy Setup console screens Easy Setup See Appendix A, Troubleshooting, for more suggestions Beginning Easy Setup Isdn Easy Setup PPP Cancel Idsl Easy Setup Easy Setup Proﬁle Previous Screen User’s Reference Guide IP Easy Setup Previous Screen Next Screen Easy Setup Security Conﬁguring Frame Relay Easy Setup Frame Relay screens Isdn Setup Isdn Line Configuration WAN Conﬁguration Frame Relay screens Frame Relay conﬁguration Easy Setup Frame Relay Dlci conﬁguration Displaying a Frame Relay Dlci conﬁguration table Changing a Frame Relay Dlci conﬁguration ADD Dlci NOW Cancel Adding a Frame Relay Dlci conﬁguration Deleting a Frame Relay Dlci conﬁguration Part II Advanced Configuration User’s Reference Guide WAN and System Conﬁguration Chapter WAN and System ConfigurationCreating a new Connection Proﬁle Add Connection Proﬁle screen appears IPX Profile Parameters Remote IPX Network BAP Telco Options Initiate Data Service 64 kb/sec Dial Default Proﬁle How the default proﬁle works Customizing the Default Proﬁle Configuration Default Profile IP parameters default proﬁle screen WAN and System Conﬁguration IPX parameters default proﬁle screen Auxiliary Port Conﬁguration System Conﬁguration screens System Conﬁguration features PAP IP Address Serving Network Protocols SetupFilter Sets Firewalls Date and Time MM/DD/YY Snmp Simple Network Management Protocol Upgrade Feature SetConsole Conﬁguration Security Telephone setup Logging Nov Specifying telephone connections Chapter Using SmartPhone for Telephone ServicesUsing SmartPhone for Telephone Services Inbound Directory Number Using SmartPhone for Telephone Services Deﬁning priority ringing Preview Ring Advanced calling features Line provisioning Conﬁguring supplementary services Call Accounting and Default Answer Proﬁle Chapter Call Accounting and Default Answer ProfileCost control feature -- call accounting Viewing call accounting statistics Call Accounting Statistics screen appears Scheduled connections Viewing scheduled connections Adding a scheduled connection Set Weekly Schedule Set Once-Only Schedule Modifying a scheduled connection Default Answer ProﬁleHow the Default Answer Proﬁle works Deleting a scheduled connection Customizing the default proﬁle Call Accounting and Default Answer Proﬁle Call acceptance scenarios IP Setup and Network Address Translation Chapter IP Setup and Network Address TranslationNetwork Address Translation features HOW NAT Works Using Network Address Translation ISP Network Address Translation guidelines Using multiple Connection ProﬁlesAssociating port numbers to nodes IP setup IP Setup and Network Address Translation Select Add Export. The Add Exported Service screen appears IP Setup IP subnets IP Setup and Network Address Translation Static routes Viewing static routes Adding a static route Deleting a static route Rules of static route installationModifying a static route Main System IP Address Menu Configuration Serving 163.176.56.90 Dhcp NetBIOS Options MacIP Kip Forwarding Options You have ﬁnished your IP Setup IPX Setup Chapter IPX SetupIPX Features IPX Deﬁnitions Socket Service Advertising Protocol SAPIPX address Routing Information Protocol RIP IPX Spooﬁng NetBIOSIPX setup Default Gateway Address IPX routing tables User’s Reference Guide AppleTalk Setup Chapter AppleTalk SetupInstalling AppleTalk AppleTalk networks AppleTalk protocol AppleTalk Setup MacIP Aurp Routers and seeding Conﬁguring AppleTalk EtherTalk Setup LocalTalk Setup Aurp Free Trade Zone Aurp setupViewing Aurp partners Adding an Aurp partner Modifying an Aurp partner Conﬁguring Aurp Options Deleting an Aurp partnerReceiving Aurp connections User’s Reference Guide Monitoring Tools Chapter Monitoring ToolsQuick View status overview General status Current status Status lights Statistics & Logs General Statistics Network Interface Event historiesPhysical Interface WAN Event History Request from our DN Routing tables Device Event History IP routing table AppleTalk routing table IPX routing tableIPX Sap Bindery table Served IP Addresses IP Address Lease Management screen appears System Information Snmp Snmp Setup screen Community strings Snmp traps Modifying IP trap receivers Setting the IP trap receiversViewing IP trap receivers Deleting IP trap receivers User’s Reference Guide Security Chapter SecuritySuggested security measures Protecting the conﬁguration screens User accountsProtecting the Security Options screen Dial-in Console Access About ﬁlters and ﬁlter sets Enable SmartStart/SmartView/Web ServerTelnet access What’s a ﬁlter and what’s a ﬁlter set? How ﬁlter sets work Filter priority Packet First filter Match? Yes ﬁltering rule How individual ﬁlters workﬁlter’s actions Parts of a ﬁlter Port numbers Port number comparisons Other ﬁlter attributes Putting the parts together UDP Filtering example #1 Design guidelines Filtering example #2 Disadvantages of ﬁlters An approach to using ﬁltersWorking with IP ﬁlters and ﬁlter sets Adding a ﬁlter set Naming a new ﬁlter set Input and output ﬁlters-source and destination Netopia R-series Router Adding ﬁlters to a ﬁlter set ADD this Filter NOW Cancel Modifying ﬁlters Viewing ﬁlter setsViewing ﬁlters Deleting ﬁlters Sample IP ﬁlter set Modifying ﬁlter setsDeleting a ﬁlter set TCP Icmp UDP Possible modiﬁcations Security IPX ﬁlters Adding a packet ﬁlter IPX packet ﬁltersViewing and modifying packet ﬁlters Viewing and modifying packet ﬁlter sets IPX packet ﬁlter setsDeleting a packet ﬁlter Adding a packet ﬁlter set ADD Filter SET NOW Cancel Viewing and modifying SAP ﬁlters IPX SAP ﬁltersDeleting a packet ﬁlter set Adding a SAP ﬁlter Viewing and modifying SAP ﬁlter sets IPX SAP ﬁlter setsDeleting a SAP ﬁlter Adding a SAP ﬁlter set Deleting a SAP ﬁlter set Basic Protocol Types Firewall tutorial General Firewall TermsBasic IP Packet Components Firewall Logic Firewall design rulesExample TCP/UDP Ports Implied Rules Binary RepresentationLogical ANDing Example IP Filter Set Screen Filter BasicsEstablished Connections Example Example FiltersExample Network Example Example Key Security Authentication Features of the Netopia R3100 Token Security AuthenticationUsing the SecurID token card Securing network environments Security authentication components Conﬁguring for security authentication Connecting using security authentication Establishing a dial-on-demand DOD connection call Current Connection Status Establishing a manual connection call User’s Reference Guide Chapter Utilities and Diagnostics Utilities and Diagnostics Ping Start Ping Utilities and Diagnostics Telnet client Stop Ping Trace Route Telnet client screen appears Secure Authentication Monitor Transferring conﬁguration and ﬁrmware ﬁles with Tftp Factory defaultsDisconnect Telnet Console Session Updating ﬁrmware Downloading conﬁguration ﬁles Uploading conﬁguration ﬁles Transferring conﬁguration and ﬁrmware ﬁles with Xmodem Do you want to send a saved configuration to your Netopia? Restarting the system Isdn Switch Loopback Test User’s Reference Guide If the loopback test fails Part III Appendixes User’s Reference Guide Troubleshooting A-1 Appendix a TroubleshootingConﬁguration problems Network problems SmartStart TroubleshootingConsole connection problems Technical support Power outagesHow to get support Before contacting Netopia Online product information FAX-Back Obtaining an Isdn line Appendix B Setting Up Telco ServicesFinding an Isdn service provider Choosing an Isdn line Isdn Ordering Codes Setup tipsPhysical Isdn line Directory and Spid numbers U models only Switch protocol typeOutside North America only Circuit ID number U models only Testing the Isdn line Long-distance Isdn calls North American models only Completing the Isdn worksheet Isdn Telco Worksheet for North America Isdn Telco Worksheet for Outside North America User’s Reference Guide Appendix C North American Telco Provisioning for Isdn North American Telco Provisioning for Isdn User’s Reference Guide Setting Up Internet Services D-1 Appendix D Setting Up Internet ServicesFinding an Internet service provider Unique requirements ISP’s Point of presence Setting up a Netopia R3100 accountPricing and support Endorsements Deciding on an ISP account With Network Address Translation Obtaining information from the ISPLocal LAN IP address information to obtain Remote WAN IP address information to obtain Remote WAN IP address information to obtain About IP addressing What is IP?Appendix E Understanding IP Addressing Understanding IP Addressing E-1 Subnets and subnet masks Subnet masks Example Using subnets on a Class C IP internetUnderstanding IP Addressing E-3 Network conﬁguration ISP Network Understanding IP Addressing E-5 Example Working with a Class C subnetDistributing IP addresses Background Technical note on subnet masking Understanding IP Addressing E-7 Netopia R3100 Dhcp Server CharacteristicsConﬁguration Dhcp Address Serving Tips and rules for distributing IP addresses Using address servingManually distributing IP addresses MacIP Serving Understanding IP Addressing E-9 Dhcp example Nested IP subnets Internet Understanding IP Addressing E-11 Broadcasts Packet header types Background Appendix F Understanding Netopia NAT BehaviorNetwork Conﬁguration Understanding Netopia NAT Behavior F-1 User’s Reference Guide Router Netopia Understanding Netopia NAT Behavior F-3 Router Netopia Exported services Understanding Netopia NAT Behavior F-5 Important notes Understanding Netopia NAT Behavior F-7 Summary Understanding Frame Relay G-1 Appendix G Understanding Frame RelayVirtual Circuits Excess Burst Size Be Committed Information Rate CIRCommitted Burst Size Bc Local Management Interface LMI AddressingLocal and Global DLCIs Understanding Frame Relay G-3 Frame Relay partial mesh support Encapsulation and FragmentationNetwork Protocol Addressing and Virtual Interfaces Understanding Frame Relay G-5 User’s Reference Guide Isdn events Appendix H Event HistoriesLeased line events Event Histories Isdn event cause codes Event Histories User’s Reference Guide Event Histories User’s Reference Guide About SPIDs Appendix Isdn Conﬁguration GuideDeﬁnitions Isdn Conﬁguration Guide Example SPIDs Dynamic B-channel usage Other incoming call restrictions User’s Reference Guide Appendix J Binary Conversion Table Binary Conversion Table J-1 Decimal Binary Appendix K Further Reading Further Reading K-1 User’s Reference Guide Further Reading K-3 User’s Reference Guide Pinouts for Auxiliary Port Modem Cable Appendix L Technical Specifications and Safety InformationTechnical Speciﬁcations and Safety Information L-1 DSR Description Power requirementsTechnical Speciﬁcations and Safety Information L-3 Environment North America Agency approvalsRegulatory notices International Technical Speciﬁcations and Safety Information L-5 Declaration for Canadian users Important safety instructionsAustralian Safety Information Battery Technical Speciﬁcations and Safety Information L-7Telecommunication installation cautions User’s Reference Guide Glossary Glossary User’s Reference Guide Glossary User’s Reference Guide Glossary Remapping See network number remapping Glossary User’s Reference Guide Index Index-1 Index-2 Index-3 ISP Index-4 NAT Index-5 Spid Index-6 Limited Warranty and Limitation of Remedies Limited Warranty and Limitation of Remedies User’s Reference Guide