Task: Define Logical Locations Model

This task defines the logical level model of locations involved in the architecture in question.

Disciplines: UAM IT Architecture

Purpose

This task finds and defines the locations involved in the architecture in question. Specifically to:

Define or refine the logical level locations;
Define or refine communications (relationships) needed between locations;
Define or refine the logical level activities/processes supported at and between each location.

Relationships

Roles	Primary Performer: Enterprise Architect	Additional Performers: Business Line or Domain Architect Business Unit or Project Architect
Inputs	Mandatory: Business Locations Model	Optional: Business Goals Business Mission Business Model Business Motivation Model Business Objective Business Process Model Business Strategy Business Vision IT Strategy Logical Locations Model Logical Process Model Migration Plan Policies and Laws Project Charter
Outputs	Logical Locations Model
Process Usage	IT Architecture Delivery > Logical Perspective Delivery > Logical Perspective Iteration [n] > Define Logical Locations Model IT Architecture Processes > Define Logical Perspective > Define Logical Locations Model

Main Description

This task defines, at the logical level, the locations involved in the IT architecture of the system. As in real-estate, locations are very important to any business in terms of the processes and tasks (i.e. business services) that are supported at each type of location. This model directly impacts upon the deployment of systems and services to the locations, which in turn defines many other factors and requirements, such as cost, network topography and requirements, deployment of servers, storage and other infrastructure services, among many others.

The Business Locations Model is used, along with input from stakeholders, to define and refine the Logical Locations Model.

Steps

Collect information about the locations

Using the Business Locations Model as input, plus any location information obtained from Task: Define Logical Process Model; these Logical Processes may provide useful input for the identifications of locations. Other sources are as-is documentation of the enterprise or relevant business domains or systems, as the case may be for the scope in question.

Define locations model

Define the logical level view of the business locations. Detail included in this view includes the tasks and processes (i.e. business services) supported at the location, therefore the Logical Process Model needs to be created and consulted as well as the Business Process Model.

Define the location relationships

Using the Business Process Model, the Logical Process Model and other sources of information, determine the services and facilities required between the locations. This includes both business level services such as "access to products and services" or infrastructure services such as "email" and "telephone". The objective of this step is to define the logical level view of services provided between locations, which will influence technical design choices.

Logical level network options are explored and decisions made regarding the topology and structure for the Local Area Network (LAN), Wide Area Network (WAN) or Metropolitan Area Network (MAN). The logical segmentation of the network is also defined, in terms of "domains" and "zones" as defined in Whitepaper: A Reference Model for Enterprise Security.

Evaluate your results

A Logical Locations Model is complete only when it describes every location that the "system" has a presence at (within the given scope) at a consistent level of detail. Before you finish, make sure the locations model exhibits the characteristics of a good locations model, see: Guideline: Logical Locations Model.

More Information

Checklists	Logical Perspective
Concepts	Complex IT Architectures Location Aspect
Guidelines	Logical Location Logical Locations Model
Supporting Materials	LPL Defined LPL Summary
Whitepapers	A Reference Model for Enterprise Security