Network Application Library Laboratory

Goals

The following laboratories will focus  on developing network architectures using the network block libraries.  The goals of this set of network-oriented laboratories are as follows:

• Develop a practical understanding of VisualSim Architect and its use for system-level design
• Understand the network library set of blocks
• Understand some of the additional basic blocks that are available for system-level design
• Develop networks based on the most common topologies
• Develop basic network-oriented traffic generators
• Converge on networks that could serve as a beginning for your modeling efforts

Network Topologies Modeled

The linear and star network topologies seem to be a good start for any network model construction.  Therefore, the laboratories will focus on the following topologies:

• Linear single-layer network topology
• Star single-layer network topology
• Linear multiple-layer network topology

Recommended Blocks for the Laboratories

VisualSim Architect has many library blocks that could be used for the development of system models.  The list below can be used initially to develop network architectures.

• Simulation block (Located in library Model->Simulator)
• Digital
• Network blocks (Located in library Application->Networking)
• Layer_Table
• Layer_Protocol
• Routing_Table
• Node
• Node_Master
• Traffic generation block
• Transaction_Source (Located in library Source->Traffic)
• Other blocks
• Processing (Located in library Defining_Flow)
• DMADatabase (Located in library Hardware_Modeling->Bus_Switch_ctrl)
• Init_Memory (Located in library Model->Memory)
• Delay (Located in library Delay and Utilities)
• Isolate Input (Located in library Delay and Utilities)
• Text Display (Located in library Results)

List of Demonstration Models

        To view the models, start VisualSim Architect and go to Demo Systems->Library Block->Applications->Networking.

• Retry_Layer1 shows the connection between Layers and Node to form the OSI stack.  It also shows the association of the Layer_Table to the Layer_Protocol.  This models shows the use of multiple Layer_Tables in the model and the setting of the retry.
• Network_External_Defn shows the Configuration Layer setting to External Delay and the conenctivity for this.
• Network_Basic shows a basic connectionless network, the Routing Table reference and the path definition in the Database block.  
• Gateway_Connected shows the use of the Node as a Gateway.
• Multi_Network_w_Intermediate_Gateway shows an intermediate of Gateway nodes.
• Gateway_w_Diff_Return shows the forward and return directions using a different Gateway Node for each direction.
• Two_Networks_w_Gateways shows two Gateways between two networks.
• Using Multicast shows the Multicast block to create a multicast and a broadcast.
• Header Compression evaluate different TCP/IP Header Compression algorithms

Laboratory 1 - Linear single-layer network

Laboratory 1: Linear Network Block Diagram

The focus of this laboratory is to use the basic network library blocks to build a network with a connected linear topology as given above.  A few things to remember:

1. The transactions sent over the network must minimally have the following fields (sample values are also given):

    input.Task_Source      = "Node_1"
    input.Task_Hop         = "Node_1"
    input.Task_Destination = "Node_4"
    input.Task_Layer       = 100
    input.Task_Size        = 150
    input.Task_Number      = input.ID
    input.Task_Trace       = {}
    input.Task_Message     = ""
    input.Task_ID           = 1

2. The network methodology is first confirm that the routing table has been properly built.  This can be done by a processor block with the following command:

    Routing_Table = getBlockStatus("RT", "stats", 1)

3. The traffic generator can be simple.  It is recommended that 1 transaction should be sent through the network in order to confirm that the setup is correct.  Laboratory 2 will focus on the development of the traffic generator.

Model: $VS/VS_AR/doc/Training_Material/Tutorial/WebHelp/Tutorial/Networking/linear_single_layer_network.xml

Laboratory 2 - Traffic Generator

The focus of this laboratory is to use the basic library blocks to build a traffic generator which satisfies the following characteristics

A.     Traffic Generator 1:   1 transaction every 10 ms
B.     Traffic Generator 2:   10 transactions every 10 ms with constant interarrival time (e.g., 1/10 ms)
C.     Traffic Generator 3:  10 transactions every 10 ms with random interarrival times

Potential building blocks:

• Transaction_Source (Located in library Source->Traffic)
• Processing (Located in library Defining_Flow)
• Init_Memory (Located in library Model->Memory)
• Delay (Located in library Delay and Utilities)
• Isolate Input (Located in library Delay and Utilities)
• Text Display (Located in library Results)

Model: $VS/VS_AR/doc/Training_Material/Tutorial/WebHelp/Tutorial/Networking/traffic_generator_model.xml

Laboratory 3 - Star single-layer network

The focus of this laboratory is to use the basic network library blocks to build a network with a connectionless star topology as given above.  Instructions from Laboratory 1 apply here.
Model: $VS/VS_AR/doc/Training_Material/Tutorial/WebHelp/Tutorial/Networking/star_single_layer_network.xml

Laboratory 3: Star Topology Single Layer

Laboratory 4 - Star single-layer network with link up/down logic

The focus of this laboratory is to use the connectionless star topology developed in Laboratory 3 and add linkup/linkdown logic using the NODE_Master block.
Model: $VS/VS_AR/doc/Training_Material/Tutorial/WebHelp/Tutorial/Networking/star_single_layer_network_with_link_up_down.xml

Laboratory 5 - Linear multiple-layer network

The focus of this laboratory is to use the connected linear topology developed in Laboratory 1 and add network layers as in the above figure using the Layer_Protocol and Layer_Table blocks.
Model: $VS/VS_AR/doc/Training_Material/Tutorial/WebHelp/Tutorial/Networking/linear_multiple_layer_network.xml

Laboratory 5: Linear Network Block Diagram

Laboratory 6 - Build request/acknowledge on multiple-layer network

The focus of this laboratory is to use the connected linear topology given above and add request and acknowledgement functionality at the entrance of either side of the network.
Model: $VS/VS_AR/doc/Training_Material/Tutorial/WebHelp/Tutorial/Networking/request_acknowledge_linear_multiple_layer_network.xml

Laboratory 6: Request/Acknowledge for Multiple Layer