Design, configuration and points for attention of network arbitrary source multicast (ASM) simulation using OPNET

About opnet The use of is no longer specified , In the last article 《 utilize OPNET Network unicast （ One server with multiple clients ） Design of simulation 、 Configuration and precautions 》 It has been explained in detail in , Here we mainly introduce the business configuration of the application layer and the related configuration of the network layer . Be careful , Not specifically stated in this case , The default configuration is generally adopted .

One 、 Configuration purpose and requirements

Multicast enables the server to send at one place , Multiple clients receive .

Two 、 The basic idea of multicast configuration

The realization of multicast mainly relies on two protocols ,PIM The protocol and IGMP agreement , among IGMP The agreement is divided into v1,v2,v3, Three versions ,v1 We can ignore ,v2 Version is for non specified source multicast ,v3 Version for specified source multicast . In this case , choose IGMPv2.PIM The protocol is oriented to the configuration between routers , Used to exchange multicast routing tables ,IGMP It is the configuration between the router and the devices inside the LAN , It is used to organize the joining and exiting of multicast members . In a complete multicast network , Each router along the way needs to support multicast routing protocol , The terminal device is required to support joining and exiting the multicast group .
therefore , stay opnet The basic idea of configuring multicast in , It's the same .

1. Configure the terminal device to support multicast protocol , In order to join and exit the multicast group .
2. Configure routers along the way to support multicast protocols ,PIM and IGMP agreement , Realize the joining and exiting of multicast members , And the forwarding of multicast data .
3. Specify on a router RP, You can specify automatic or static RP. dynamic RP Need to start the RP The campaign mechanism .
4. Configure the data sender , The destination of data transmission is the specified multicast address .
5. Configure the data receiving end , Receive data from the specified multicast group .

3、 ... and 、 Similarities and differences between multicast and unicast configurations

（ One ） The same thing

1. The topology is the same .
2. The basic network configuration remains unchanged , such as IP Configuration etc. , The premise of multicast is that the network is unblocked .

（ Two ） Difference

1、 Apply business configurator

a) Multiple services need to be configured in unicast , In multicast, only one service flow needs to be configured .

2、 Policy Configurator

a) A business flow of a business , Therefore, only one policy needs to be configured .

3、 Server side configuration

a) You need to configure and enable multicast .IP->IP Host Parameters->Multicast Mode, Modify value Enabled.
b) Modify the destination address to the specified multicast address , Such as 224.0.6.1.Applicaitions->Application:Destination Preferences->Actual Name->Name, It is amended as follows 224.0.6.1.
c) Configuration business is not detailed , Consistent with unicast .

4、 Client configuration

a) You need to configure and enable multicast .IP->IP Host Parameters->Multicast Mode, Modify value Enabled.
b) Configure the multicast address for receiving data .Applicaitions->Application:Multicasting Specification, To configure Application Name by video（ According to your own needs ）, To configure Membership Addresses For multicast address , namely 224.0.6.1.
c) Supported businesses , Consistent with unicast .

5、 Router configuration

a) Enable Multicast Protocol .IP Multicasting->IP Multicast Parameters->Multicast Routing, Not modified Enabled.
b) Specify the port using multicast protocol .IP Multicasting->IP Multicast Parameters->Interface Information, It is recommended to add all UP Connected port ,Status by enable,Routing Protocol(s) by PIM-SM.
c) Enable PIM agreement .IP Multicasting->PIM Parameters->Status, It is amended as follows Enabled.
d) Specify the use of PIM Protocol port .IP Multicasting->PIM Parameters->Interface Information. It is recommended to add all UP Connected port ,Version by 2.
d) Specify the use of IGMP Protocol port .IP Multicasting->IGMP Parameters->Interface Information. It is recommended to add all UP Connected port ,Status by Enabled, Version by 2.
e) Configuration dynamics RP.IP Multicasting->PIM Parameters->Auto-RP Configuration Several modifications are made below , Enable dynamic RP, modify Discover by Enabled, Enable mapping ,Map Configuration->Status by Enabled,Candidate RP Configuration Next add a line , To configure Status by Enabled,Address/Interface Value , You need to specify a port to connect here , It can be the name of this port , It can also be port IP,Candidate RP Configuration->Group Filter Configuration->Groups Add the address of multicast group under , For example, fill in 224.0.6.1/32, Be careful , Mask .

Four 、 Be careful

1. The multicast addresses sent and received must be consistent .
2. Check more IGMP and PIM Whether the configuration port information of is correct . namely IP Multicast Parameters,PIM Parameters,IGMP Parameters Under the Interface Information, Be sure to check more , If the configuration is wrong , It won't work . The suggestion is to put all UP All ports are configured .
3. The above configuration is only applicable to ASM, That is, unspecified source multicast .