Exercise 6 Network Communications

System Architecture Design Strategies (select here for table of contents)
1. System Design Process	2. GIS Software Technology	3. Software Performance	4. Server Software Performance
5. GIS Data Administration	6. Network Communications	7. Platform Performance	8. Information Security
9. GIS Product Architecture	10. Performance Management	11. City of Rome	12. System Implementation

Network traffic contention is the most common cause of distributed GIS performance problems. Traffic contention occurs when network traffic throughput demands exceed available network bandwidth.

• Enterprise GIS deployment often significantly increases traffic over limited WAN and Internet service connections.
• Network bandwidth connections often must be increased to handle peak traffic loads to satisfy user productivity requirements.

Use the CPT to evaluate network bandwidth requirements.

Use the CPT to explore network communications

In this exercise, you will perform the following tasks:

• Use the CPT Calculator to select web mapping specifications (recipe) that best satisfies business needs.
• Use the CPT Design tab to demonstrate network bandwidth impact on user display response times.
• Use the CPT Design tab to identify reduced productivity expectations due to bandwidth congestion.
• Use the CPT Design tab to represent business requirements for a distributed system design.
• Use the CPT Design tab to identify required network bandwidth based on business requirements.

Step 1: Use the CPT Calculator to evaluate web mapping display performance for remote shared low-bandwidth sites

First, you will use the CPT Calculator workflow source selection to select a project workflow.

Best practice: Use the Copy Sheet command to save a copy of the Calculator on a new tab, and label it 6.1.

• In cell range C30:D30, select Workflow tab as the Workflow Source.
• In cell range E30:I30, select WebMap project workflow.

Tip: The Workflow Source selection (C30:D30) allows you to select established project workflows or standard workflows for review on the Calculator tab. Select the following user requirements and data source.

Note: The Calculator Software Technology Performance Factors section is disabled when the Workflow tab is selected as the Workflow Source.

• Select the following hardware architecture and network settings (white cells).

Note: Peak remote site concurrent users are 10 and 4 for this exercise, latency is 10 msec for Remote site 1 and 0 msec for Remote site 2, and network bandwidth (column G) is 3 Mbps for remote site 1 and 1.5 Mbps for remote site 2.

Warning: Update the white cells only. Colored cells contain formulas used to complete the CPT Calculator design analysis.

• Evaluate the display response times for the WebMap workflow.

Question 1. Identify the average display response times for clients on the local, remote site 1, and remote site 2 networks, respectively. ____sec, ____sec, ____sec

Step 2: What are the performance advantages of using an optimized web service?

• Use the same user requirements and hardware configuration from Step 1, and use the CPT Calculator tab (not a copy) to generate performance targets for the following optimized web service:

Evaluate the display response times for the WebLite workflows.

Question 2. Identify the average display response times for clients on the local, remote site 1, and remote site 2 networks, respectively. ____sec, ____sec, ____sec

Project workflow performance comparison:

Best practice: Selecting an optimum application deployment pattern can significantly reduce licensing cost and improve web mapping performance.

Step 3: Add custom WebLite workflow to project workflows

• Select and copy one of your existing project workflow rows, and insert the copied cells to add a new workflow.

You will use the new workflow row as a template for adding custom workflow values as a new project workflow.

• Locate the Calculator workflow section at the bottom of the CPT Workflow tab.

Warning: You must first configure new custom CPT workflows on the CPT Calculator tab before they show up as a Calculator Workflow on the Workflow tab.

• Select and copy the blue Calculator Workflow row cells (columns A through O).
• Select the new project workflow template cell in column A, and Paste Special/Values to insert the new Calculator-generated workflow service times into the new project workflow.

Best practice: It is good practice to copy the workflow recipe (column A) and Paste Special/Values into the workflow description column (located in column AF) to document the workflow source.

• Insert the Nickname (WebLite_) as the new workflow prefix.

Question 3. What is the total Arc19 baseline processing time (column P) for the WebLite workflow? _____ sec

Step 4: Configure the design to represent business requirements for local and remote site users

Best practice: Use the Copy Sheet command to save a copy of the Design1 tab updated in Lesson 2 on a new end tab, and label it 6.14.

Note: The Design1 tab used in Lesson 2 evaluated the central data center network bandwidth requirements, but did not evaluate bandwidth requirements for remote site locations. In this lesson, you will add the remote locations to this design.

During your business needs assessment, you compiled the following information on user locations and peak usage for each project workflow. The following chart includes remote site user locations and network bandwidth connections for users located on the WAN.

• Expand the CPT Design tab to include an evaluation of the remote site bandwidth connections.

• Select and copy the green row located at the bottom of the Requirements Analysis module.

• Use the Excel Insert Copied Cells function to insert the green row (remote site template) just below the data center WAN row (this will insert a remote site within the WAN network).

Tip: The green remote site row template is configured to provide a default name for the remote site. You can change the default name to identify each remote site as appropriate for your design.

• Select and copy the green remote site template before inserting each additional remote site network.

• Select any row between the remaining WAN workflows, and use the Excel Insert Copied Cells function to insert a second remote site.

Warning: Always select a complete workflow row when you add remote sites. The automatic naming convention will not work properly if you insert a remote site immediately above a network row.

• Follow the previous procedures to add one additional remote site network just below the data center Internet network gray row.

Warning: After you start including remote site locations, a green remote site network row must be located just below each of the following data center gray network rows.

• Configure the workflows for each remote site location.

• Add additional workflows to establish three for each remote site.

• Select proper project workflows for each location.

Note: Workflows are added using the same type of procedure used for adding remote site locations. Copy an existing workflow row to use as a template, and use the Excel Insert Copied Cells function to add additional workflows.

Tip: You can use the WebMap workflow row as a template for adding a WebMap workflow to remote site 1. You can similarly use the CitrixView workflow row as a template for adding a CitrixView workflow to remote site 2.

• Select the appropriate workflows for each site (drop-down selection from project workflows).

• LAN clients (DeskEdit, DeskView, and WebMap)

• Remote site 1 clients (CitrixEdit, CitrixView, WebMap)

• Remote site 2 clients (CitrixEdit, CitrixView, WebMap)

• Internet/remote site 3 clients (WebLite)

Best practice: Use the WebLite workflow created earlier in this lesson in place of the WebMap workflow for the public Internet clients.

•In columns C and D, update peak user requirements for each remote location workflow.

• In column H, provide the existing remote site bandwidth connections.

• 1.5 Mbps for remote site 1 and remote site 2

• 90 Mbps for the remote site 3 public Internet connections (match data center bandwidth)

• Next, you will complete configuration for network suitability analysis.

• Identify the required network upgrades.

After you configure the user workflows, update peak user requirements, and update the network traffic bandwidth, Excel will complete the network suitability analysis. Red cells will identify invalid workflow productivity and network traffic bottlenecks. In most cases, you can remove workflow productivity issues by upgrading network bandwidth.

Best practice: Use the Copy Sheet command to save a copy of the 6.14 Design tab on a new end tab for network upgrade purposes.

Note: Saving a sheet showing the network traffic bottlenecks is helpful when reviewing your design.

• As a general guideline, recommended network bandwidth is roughly twice the projected traffic loads.

Tip: If you rent network segments from a service provider, these costs are normally monthly charges based on available bandwidth and are part of the network administrator's budget. For this reason, you must coordinate bandwidth upgrades with the network administrator.

• For this design, make the following network bandwidth upgrades in column H.

• WAN = 135 Mbps

• Remote site 1 = 90 Mbps

• Remote site 2 = 45Mbps

• Internet/remote site 3 = 45 Mbps (match data center bandwidth)

Note: The network traffic column turns yellow when traffic exceeds 50 percent of selected network bandwidth. Selections close to 50 percent are often acceptable (you can review relative performance impacts on the Workflow Performance Summary chart).

Tip: Network bandwidth selections (Standard bandwidths are provided at the bottom of the drop-down selection) are normally based on standard offerings (T-1 = 1.5 Mbps, 2x T-1 = 3.0 Mbps, T-2 = 6 Mbps, 2x T-2 = 12 Mbps, 3x T-2 = 18 Mbps, 4x T-2 = 24 Mbps, T-3 = 45 Mbps, and so on). The CPT will also accept unique bandwidth entries.

• Select 'Minimum' (Cell H25) to generate a minimum platform solution.

• After you complete your network design, Excel completes the system architecture design analysis.

Best practice: The custom WebLite Internet traffic is much less than the WebMap services used in the earlier Lesson 2 design. Total GIS Server processing load was also significantly reduced.

Question 4. What is the data center WAN network utilization (Column I)? _____ percent

Question 5. What is the data center Internet/remote site 3 network utilization (Column I)? _____ percent

Question 6. What is the remote site 2 network utilization (Column I)? _____ percent

Note: The Traffic cell turns yellow when traffic exceeds 50 percent of available bandwidth.

Question 7. What is the Internet WebLite average display response time (Column V)? _____ sec

Question 8. What are the ArcGIS Server licensing requirements? _____ cores

Note: ArcGIS Server licensing requirements were 8 cores for the WebMap workflow in Lesson 2.

Answers to Lesson 6 questions

• 1. Identify the average display response times for clients on the local, remote site 1, and remote site 2 networks, respectively. 0.37 sec, 4.64 sec, 4.51 sec
• 2. Identify the average display response times for clients on the local, remote site 1, and remote site 2 networks, respectively. 0.12 sec, 0.58 sec, 0.80 sec
• 3. What is the total Arc19 baseline processing time (column P) for the WebLite workflow? 0.087 sec
• 4. What is the data center WAN network utilization (Column I)? 48 percent
• 5. What is the data center Internet/remote site 3 network utilization (Column I)? 38 percent
• 6. What is the remote site 2 network utilization (Column I)? 51 percent
• 7. What is the Internet WebLite average display response time (Column V)? 0.15 sec
• 8. What are the ArcGIS Server licensing requirements? Up to 4 cores

Lesson 6 CPT Exercise review

• Exercise 06 completed CPT workbook
• CPT Exercise Video: Lesson 6 Exercise overview 8:28

System Architecture Design Strategies (select here for table of contents)
1. System Design Process	2. GIS Software Technology	3. Software Performance	4. Server Software Performance
5. GIS Data Administration	6. Network Communications	7. Platform Performance	8. Information Security
9. GIS Product Architecture	10. Performance Management	11. City of Rome	12. System Implementation