Survey Methods

There are various survey methods. Enterprises should select what is most appropriate for them in terms of survey efficiency, completeness, and authenticity. Generally, CMDB is most recommended. If there is missing information, use the cloud management platform or conduct surveys and interviews.

The following table lists the typical survey methods. Enterprises should conduct surveys in an easy-to-difficult manner. Some service providers may provide massive survey forms for enterprises, which is inefficient and error-prone. Use information systems such as CMDB if possible. For security purposes, enterprises can provide read-only accounts for investigators to obtain information from CMDB, or they can export the required data directly.

**Table 1** Scenarios of different survey methods
No.	Method	Scenario	Advantages	Disadvantages
1	CMDB on the live network	The customer has CMDB with the application calling module.	Directly and efficiently obtain the survey information, including the detailed resource list and connections between data layers and application layers.	The system information in the old-version CMDB is not updated in time.
2	Cloud management platform on the live network	The customer has CMP or a virtualization management platform.	Accurately obtain resource details.	Information such as the application architecture and association cannot be obtained.
3	Existing documents	The customer has complete device archives, including design documents and implementation solutions.	Quickly obtain the live network information.	The timeliness and integrity of the documents cannot be guaranteed.
4	Installation tools (RDA/third-party)	The customer agrees to install the tool agent.	Quickly obtain the detailed resource list.	1. Installing the agent on the customer's live network is security-sensitive. 2. Only a small amount of information can be obtained from databases and middleware, and the application invocation relationship is not available.
5	Surveys and interviews	The customer has sufficient manpower and time and is willing to cooperate.	The customer business team is responsible for the resource list and application invocation relationship.	1. The survey period cannot be controlled. 2. The accuracy and completeness of survey information is uncontrollable.

The efficiency, completeness, and authenticity of obtained information vary among survey methods. Generally, CMDB is the most efficient survey method.

**Table 2** Comparison of different survey methods
Survey Channel	Application Architecture Survey					Technical Architecture Survey					Method Evaluation
Survey Channel	Service panorama	Service domain	Service system	Application system module	Association between applications	Technical architecture (Overall)	Technical architecture (by service domain)	Technical architecture (by service system)	Technical architecture (by application system module)	Technical architecture (technical component details)	Efficiency	Completeness	Authenticity
CMDB on the live network	√ Sorting required	√ Sorting required	√	√	√	√ Sorting required	√ Sorting required	√ Sorting required	√	√	High	High	Medium-high or high
Cloud management platform on the live network	-	-	-	-	-	-	-	-	-	√	High	Low	High
Existing knowledge base	√ Possibly exist	√ Possibly exist	√ Possibly exist	√ Possibly exist	√ Possibly exist	√ Possibly exist	√ Possibly exist	√ Possibly exist	√ Possibly exist	√ Possibly exist	High	Low/Medium/High All possible	Low/Medium/High All possible
Collection using the RDA tool	-	-	-	-	-	-	-	-	-	√	Medium	Low	High
Surveys and interviews	√	√	√	√	√	√	√	√	√	√	Low	High	Medium-high