Black Box LR1530A-EU-R3, LR1530A-R3 manual Appendix B Octet Locations on Ethernet Frames

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APPENDIX B

OCTET LOCATIONS ON

ETHERNET FRAMES

This appendix provides octet locations for the various portions of three of the common Ethernet frames. When creating pattern filters these diagrams will assist in the correct definition of the patterns. The offset numbers are indicated by the numbers above the frame representations.

Note the differences in the TCP/IP and Novell frames when bridging and when routing. When routing, the TCP/IP and Novell frames are examined after the Level 2 Ethernet portion of the frame has been stripped from the whole data frame. This means that the offset numbers now start from 0 at the beginning of the routed frame and not the bridged frame.

Some of the common Ethernet type codes are also shown here. The Ethernet type codes are located at offset 12 of the bridged Ethernet frame.

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Contents Frame Relay/Leased Line Bridge/Router Specifications Normas Oficiales Mexicanas Electrical Safety Statement Page Page Page Contents Introduction to Filtering Appendix D Software Upgrades Page Select a Site Unpack the unitRear View of the CSU-DSU router Identify the ConnectorsMake the LAN Connections Connect to the ConsoleMake the WAN Link Connection Installation Login and Enter the Required Configuration Power Up the routerMandatory Configuration Mandatory ConfigurationSet Link Interface Type Location Main Setting the Link Interface TypeLink Interface Type Service parameters Location Main Setting the T1/E1ParametersT1/E1 Selection Location Main Framed/unframed/SF/ESFFirst channel Number number of channels As specifedSet Link Interface Type Location Main Green Identify the Status LEDsFront View of the router Typical Applications & HOW to Configure Them Managing the router Using Menus Conventions Configuration Option Name Location MainOption Name Frame Relay configuration Basic Frame Relay ConfigurationLink Speed Location Main Frame Relay enable Location MainLink Speed Auto Learning the Frame Relay Configuration Auto-Learning Location Main Manual Configuration LMI TypeLMI Type IP Address Quick Start Frame RelayIP Address / Subnet mask size PPP Encapsulation Location Main Frame Relay disable Location Main Basic Leased Line ConfigurationDisabled Quick Start PPP Leased Line ConnectionsLocal IP Address Location Main Basic PPP Leased Line ConfigurationBridge Connection Should You Bridge or Route? Bridged Local Area Networks Configure as an Ethernet BridgeIP Address Applications IP Routed Local Area Networks Configure as an Ethernet IP routerIP Address Default Gateway Location Main Define an IP Default GatewayDefault Gateway Edit Static Route Location Main Define an IP Static RouteRemote Site Next Hop Cost Add Define an IP Subnet Mask IP Address / mask size IP Address & Subnet Size Location MainApplications Novell Servers in Both Locations Configure as an Ethernet IPX routerApplications IPX Routed Local Area Networks Servers on one side Novell Servers in One Location OnlyIPX Frame Types Location Main Numbered Links PPP Link Configuration OverviewUnnumbered Links Dhcp Services Location Main Configure Dynamic Host Configuration ProtocolServer IP Address Pool Location MainDNS Set-Up Location Main Local + External DNS Server ConfigurationNAT Enabled Location Main Configure Network Address Translation NATEnabled NAT ExportsTranslation type Location Main Security Level Location Main Configure PPP SecuritySecurity Level Outgoing PAP Password Outgoing Chap Secret Incoming PAP Password Incoming Chap SecretSecurity Database Entry Location Main 10 Sample Firewall Application Configure FirewallFTP & WWW Designated Servers Location Main Firewall WAN Remote Site Filter direction Location MainFirewall Table Entry Location Main Firewall LAN Filter Direction Location MainFirewall Location Main Applications Introduction to Filtering MAC Address FilteringPattern Filtering Not Introduction to Filtering Popular Filters NetBIOS &NetBEUI Microsoft WindowsBridge IP & Related TrafficBanyan NetBIOS over TCPIP Router Other interesting TCP PortsAppendix a Menu Trees Menu Tree From previous Page Appendix B Octet Locations on Ethernet Frames Octet Locations on Ethernet Frames ARP Ethernet Type CodesOctet Locations on Ethernet Frames Octet Locations on a Bridged XNS Frame Octet Locations on Ethernet Frames Appendix C Servicing Information Opening the caseCPU Identifying the Internal ComponentsJ11 To Clear a Lost Password Sanity TimerForce Zmodem Software Load Figure C-3 Rear View of the Console and LAN Connectors Connecting to the Console ConnectorPinout Information WAN Interface ConnectionModule CSU/DSU ModuleT1/E1 T1/E1 ModuleUniversal WAN Module Link Pinouts Connecting cable must be a shielded cableServicing Information DCE RS232C / V.24 Link PinoutsFigure C-8 RS530 / RS422 Link Pinouts RS530 / RS422 Link PinoutsFigure C-9 V.11 / X.21 Link Pinouts 11 / X.21 Link PinoutsFigure C-10 V.11 / X.21 DB25 to DB15 Connector Cable 11 / X.21 DB25 to DB15 Connector CableFigure C 11 V.35 Null-Modem Cable Null-Modem Cable ConfigurationFigure C-12 RS232 / V.24 Null-Modem Cable RS232 / V.24 Null-Modem CableRS530 / RS422 Null-Modem Cable Signal Ground DTE Ready aServicing Information Appendix D Software Upgrades Considerations Servicing Information Page PC used for Tftp transfers Link