Moxa Technologies PT-7728 user manual Benefits of Multicast, Multicast Filtering

Page 59

PT-7728 User’s Manual

Featured Functions

Benefits of Multicast

The benefits of using IP multicast are that it:

yUses the most efficient, sensible method to deliver the same information to many receivers with only one transmission.

yReduces the load on the source (for example, a server) since it will not need to produce several copies of the same data.

yMakes efficient use of network bandwidth and scales well as the number of multicast group members increases.

yWorks with other IP protocols and services, such as Quality of Service (QoS).

Multicast transmission makes more sense and is more efficient than unicast transmission for some applications. For example, multicasts are often used for video-conferencing, since high volumes of traffic must be sent to several end-stations at the same time, but where broadcasting the traffic to all end-stations would cause a substantial reduction in network performance. Furthermore, several industrial automation protocols, such as Allen-Bradley, EtherNet/IP, Siemens Profibus, and Foundation Fieldbus HSE (High Speed Ethernet), use multicast. These industrial Ethernet protocols use publisher/subscriber communications models by multicasting packets that could flood a network with heavy traffic. IGMP Snooping is used to prune multicast traffic so that it travels only to those end destinations that require the traffic, reducing the amount of traffic on the Ethernet LAN.

Multicast Filtering

Multicast filtering ensures that only end-stations that have joined certain groups receive multicast traffic. With multicast filtering, network devices only forward multicast traffic to the ports that are connected to registered end-stations. The following two figures illustrate how a network behaves without multicast filtering, and with multicast filtering.

Network without multicast filtering

M1

M2

M3

M4

PT-7728

All hosts receive the multicast traffic, even if they don’t need it.

3-45

Image 59

Contents First Edition, February Moxa Inc Moxa PowerTrans Switch PT-7728 User’s ManualDisclaimer Copyright NoticeTrademarks Table of Contents Appendix a MIB Groups Appendix B Specifications Introduction ‰ Overview ‰ Package Checklist ‰ Software FeaturesOverview Package ChecklistSoftware Features Getting Started Serial Console Configuration 115200, None, 8, 1, VT100 PT-7728 User’s Manual Getting Started Key Function Configuration by Telnet ConsolePT-7728 User’s Manual Getting Started PT-7728 User’s Manual Getting Started Configuration by Web Browser Disabling Telnet and Browser Access Featured Functions System Identification Configuring Basic SettingsAccount PasswordPassword Hosts That Need Access Input Format Accessible IPGrant access to one host with a specific IP address Grant access to any host on a specific subnetworkName EnablePort DescriptionFDX Flow Ctrl NetworkSpeed Default Gateway Auto IP ConfigurationSwitch IP Address Switch Subnet MaskCurrent Date TimeDaylight Saving Time Current TimeSystem File Update-By Remote Tftp Log Files Path and Name Configuration Files Path and NameTftp Server IP/Name Firmware Files Path and NameFactory Default System File Update-By Local Import/ExportPort Trunking Concept Using Port TrunkingAvailable Ports/Member Ports Configuring Port TrunkingTrunk Group Maximum of 4 trunk groups Trunk TypeTrunk Table Configuring SnmpSetting Description V1, V2c Write/Read Community Snmp Read/Write SettingsSnmp Versions V1, V2c Read Community1st Trap Server IP/Name Setting Description Factory Default Setting Description Factory DefaultPrivate MIB information Using Communication RedundancyTurbo Ring Concept Initial setup for Turbo Ring or Turbo RingTurbo Ring with odd number switches Determining the Redundant Path for Turbo Ring Ring Coupling ConfigurationSwitch B Configuring Turbo Ring Configuring Turbo Ring and Turbo RingDual-Homing Configuration for Turbo Ring Set as Master Now ActiveMaster/Slave Redundancy ProtocolCoupling Control Port Enable Ring CouplingCoupling Port Coupling-Mode Enable RingRing 1/2-Status Ring 1/2-1st Ring Port Status Ring 1/2-2nd Ring Port StatusPrimary/Backup Port Coupling ModeSTP/RSTP Concept What is STP?PT-7728 User’s Manual Featured Functions Port Speed Path Cost 802.1D Edition 802.1w-2001 STP ConfigurationHow STP Works STP RequirementsSTP Example STP ReconfigurationDifferences between Rstp and STP Using STP on a Network with Multiple VLANs Bridge Priority Configuring STP/RSTPRoot/Not Root Protocol of RedundancyMax. Age sec Forwarding DelayEnable STP per Port Hello Time secTraffic Prioritization Concept Using Traffic PrioritizationConfiguration Limits of RSTP/STP What is Traffic Prioritization?Ieee 802.1p Priority Level Ieee 802.1D Traffic Type How Traffic Prioritization WorksTraffic Queues Differentiated Services DiffServ Traffic MarkingTraffic Prioritization Inspect TOS Configuring Traffic PrioritizationQoS Classification Queuing MechanismInspect COS Setting Description FactoryCoS Mapping TOS/DiffServ MappingVirtual LAN Vlan Concept Using Virtual LANWhat is a VLAN? Communication Between VLANs VLANs and the PowerTransBenefits of VLANs Managing a VlanVLANs Tagged and Untagged Membership Sample Applications of VLANs using PT-7728PT-7728 User’s Manual Featured Functions Port Type Configuring Virtual LANVlan Settings Management Vlan IDVlan Table Using Multicast FilteringWhat is an IP Multicast? Concept of Multicast FilteringNetwork without multicast filtering Benefits of MulticastMulticast Filtering Network with multicast filtering Multicast Filtering and Moxa PowerTrans SwitchIgmp Internet Group Management Protocol Snooping Mode Query ModeStatic Multicast MAC Configuring Igmp SnoopingIgmp Multicast Filtering Gmrp Garp Multicast Registration ProtocolIgmp Snooping Settings Add Static Multicast MAC Gmrp Table Using Bandwidth ManagementConfiguring Gmrp Gmrp enableIngress Configuring Bandwidth Management Broadcast Storm ProtectionTraffic Rate Limiting Settings Ieee Using Port Access ControlConfiguring Static Port Lock Static Port LockServer Port Configuring IeeeDatabase Option Radius ServerLocal User Database Setup 802.1X Re-AuthenticationLocal User Database Setup Using Auto WarningPort Access Control Table Event Type Configuring Email WarningMail Server IP/Name Email SetupMoxaPowerTransSwitch0001@SwitchLocation Port EventsEmail Address Configuring Relay WarningPassword Setting Account NameEvent Setup Override relay alarm settings Using Line-Swap-Fast-RecoveryUsing Set Device IP Configuring Line-Swap Fast RecoverySet up the connected devices Configuring Set Device IPMirror Port Using DiagnosisPing Using MonitorMonitor by Switch Monitor by Port Using the MAC Address TableMAC Using Event LogSyslog Server Using SyslogPT-7728 User’s Manual Featured Functions MIB II.5 Icmp Group MIB II.1 System GroupMIB II.2 Interfaces Group MIB II.4 IP GroupMIB II.17 dot1dBridge Group MIB II.10 Transmission GroupMIB II.11 Snmp Group Private Traps Public TrapsInterface Switch PropertiesTechnology Optical Fiber 100BaseFX PowerEnvironmental WarrantyMechanical