Black Box Version 1.0 user manual Routing of networks, Routing components

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Fig. 5: Network after running STA

The spanning-tree calculation occurs when the bridge is powered up and whenever a topology change is detected. The calculation requires communication between the spanning-tree bridges, which is implemented through configuration messages. Configuration messages contain information identifying the bridge that is assumed to be the root (root identifier) and the distance from the sending bridge to the root bridge (root path cost) and also the bridge and port identifier of the sending bridge and the age of information contained in the configuration message.

Bridges exchange configuration messages at regular intervals (typically 1–4 s). If a bridge fails (causing a topology change), neighboring bridges will soon detect the lack of configuration messages and initiate a spanning-tree recalculation.

The MDS92xxx-10BT device implements both transparent bridge and spanning tree algorithms.

4.2.4 Routing of networks

The word “routing” means forwarding information through an internetwork from source to destination. At least one node must be passed when transmitting data. Routing is often contrasted with bridging. The main difference between bridging and routing consists in the fact that bridging occurs at the data link layer of the OSI reference model, while routing occurs at the network layer. It means that routing and bridging use different information while moving it from source to destination. It results in different way of implementing their tasks.

4.2.4.1 Routing components

Routing consists of two basic activities: determination of optimal routing paths between source and destination and data transmission through network. The latter is called switching.

Version: 1.0

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Contents Ethernet Router / Bridge MDS921AE-10BT MDS922AE-10BTSpecifications Firmware Loading Description of Interface Cables Major changes to previous version Version ControlIntroduction Version Specification XDSL technology, background TechnologiesAsymmetric DSL Adsl technology Adsl in briefLine code Isdn DSL technologyNumber of pairs UsageHigh bit rate DSL Hdsl technology Idsl in briefStandard Transmission rateHdsl in brief EXTRAns in brief EXTRAns technologyMdsl in brief Multispeed DSL Mdsl technologyMSDSL, in brief Multispeed DSL Msdsl technologyTransmission medium Straight-line code7.1 G.shdsl, in brief 7 G.shdsl technology1 TCP/IP stack structure Local area network integration. Access to InternetLayer Correspondence of TCP/IP layers with the OSI model layers IP address classes Address assignment in IP networksMasks Automatic assignment of IP addressesTypes of bridges Bridging of local networks Simple network Version Network before running STA Routing components Routing of networksOptimal path determination Change of packet addresses SwitchingRouting algorithms, RIP Internet Access through LANs, NATStatic Network Address Translation NAT functioningDynamic Address Translation Masquerading NAPT, PATInternal IP Port local NAT port 191.167.0.10 1243 61300 Background Description of the DeviceStructural schematic of MDS92xxx-10BT Master/Slave mode Operation modeConnection at a fixed speed Fixed Mode Connection with an automatic speed regulation Adaptive modeRoute mode Bridge modeEthernet 10BaseT interface ATM interfaceLED Description of LEDsSub-Rack Mechanic DesignMDS920C-10BT, NG, front panel Xdsl Mini-RackMDS922AE-10BT, front panel LED Stand AloneEquipment Installation Version Introduction Programming GuideManagement of devices of Sub-Rack type Management of devices of Mini-Rack and Stand Alone type Command structureCommand tree of bridge mode Command tree of router mode Help command Main menu of the bridge modeHome command Security password from an unauthorized accessLan command Default commandSetip command Show commandList command Setpass command Manage commandPassword setting Password disablement Password changeBridge mode setting mode Mode commandRouter mode setting mode Quick command Ping commandANY 10 R1483 commandPfilter command Delpvc commandSetpvc command Setspan command Setqos commandRestart command 10.6 6 Show commandSave command Shdsl shdsl Shdsl commandTerminal command Enable commandAnnex command Adapt command Fix commandPRE Activation Status commandMain menu of the router mode Default command Ver commandDnsrelay command Setdnsip command Delwanip command Ipoa commandSetwanip command Setrip commandDhcpserver command Setdhcp command Addpatin command Pat commandSetpat command Delpatin commandPppoa command Chpass command Adduser commandDeluser command Setllc command Echo commandPppoe command 12 R1483 command 12.4 8.3.12.4 Setwanip command WAN Addiproute Rtable commandDeliproute All Deletes Firmware loading guide Firmware LoadingInterfaces Monitor interface Technical SpecificationsNetwork management interface Network interface Protection against dangerous affects Surge safety10.3 10.3 Climatic conditions 10.5 10.5 Physical dimensions 10.4 10.4 GuaranteeShdsl connector CONNECTORS’ DescriptionMonitor connector Power connector For MDS922AE-10BT Ethernet 10BaseT connector12.1 «Direct» Ethernet cable Description of Interface CablesCross-over Ethernet cable Typically the delivery set includes Delivery SETGlossary RJ45 RJ11RS232 SplitterTDM Router Example of Network ConfigurationVersion Ethernet IP Subnet mask 0.0.0.0 WAN IP Gateway