

DigitalHome Software Requirements Specification 
HomeOwner Inc. 
                                          
DigitalHomeOwner Division 
Version 1.3 
October 27, 2010

Digital Home Project, SRS 1.3 Page 2 
 
Change History

*Added (A), Modified (M), Deleted (D) 
 
Version Date AMD* Author Description Change 
Request # 
1.0 10/11/2010 A Michel 
Jackson 
First Version 
1.1 10/15/2010 AM Michel 
Jackson 
Updated version, based on 
external review 
1,2,3, 4, 5, 
6, 7 
1.2 10/18/2010 AM Michel 
Jackson 
Updated version, based on 
management requests 
8, 9 
1.3 10/27/2010 AM Michel 
Jackson 
Updated version, based on 
SRS Inspection. Added 
Use Case Model. 
10, 11, 12

   Digital Home Project, SRS 1.3 Page 3 
 
Table of Contents 
 
1. Introduction .................................................................................................... 4 
2. Team Project Information .............................................................................. 4 
3. Overall description ......................................................................................... 5 
3.1 Product Description and Scope ............................................................... 5 
3.2 Users Description .................................................................................... 5 
3.3 Development Constraints ......................................................................... 6 
3.4 Operational Environment ......................................................................... 6 
4. Functional Requirements ............................................................................... 8 
4.1 General Requirements ............................................................................. 8 
4.2 Thermostat Requirements ....................................................................... 8 
4.3 Humidistat Requirements ......................................................................... 9 
4.4 Security System Requirements .............................................................. 10 
4.5 Appliance Management Requirements .................................................. 10 
4.6 DH Planning and Reporting Requirements ............................................ 10 
5. Other Non-Functional Requirements ........................................................... 11 
5.1 Performance Requirements ................................................................... 11 
5.2 Reliability ............................................................................................... 11 
5.3 Safety Requirements ............................................................................. 12 
5.4 Security Requirements .......................................................................... 12 
5.5 Maintenance Requirements ................................................................... 12 
5.6 Business Rules ...................................................................................... 12 
5.7 User Documentation: ............................................................................. 13 
6. Glossary ...................................................................................................... 14 
7. References .................................................................................................. 15

 Digital Home Project, SRS 1.3 Page 4 
 
DigitalHome Requirements Specification 
1. Introduction 
This document specifies the requirements for the development of a “Smart 
House”, called DigitalHome (DH), by the DigitalHomeOwner Division of 
HomeOwner Inc. A “Smart House” is a home management system that allows 
home residents to easily manage their daily lives by providing for a lifestyle that 
brings together security, environmental and energy management (temperature, 
humidity and lighting), entertainment, and communications. The Smart House 
components consist of household devices (e.g., a heating and air conditioning 
unit, a security system, and small appliances and lighting units, etc.), sensors 
and controllers for the devices, communication links between the components, 
and a computer system, which will manage the components. 
 
The DigitalHome Software Requirements Specification (SRS) is based on the 
DigitalHome Customer Need Statement . It is made up of a list of the principal 
features of the system. This initial version of DigitalHome will be a limited 
prototype version, which will be used by HomeOwner management to make 
business decisions about the future commercial development of 
DigitalHomeOwner products and services. Hence, the SRS is not intended as a 
comprehensive or complete specification of DigitalHome requirements. There is 
a supplementary document that provides additional detail and information about 
the DigitalHome requirements: the Digital Home Use Case Model [HO2010]. 
These document were prepared by the DigitalHomeOwner Division, in 
consultation with the Marketing Division of HomeOwner Inc. 
2. Team Project Information 
• Members/Roles 
− Team Leader: Disha Chandra 
− System Analyst and Requirements Manager: Michel Ja ckson 
− System Architect and Design Manager: Yao Wang 
− Planning Manager: Georgia Magee 
− Quality Manager: Massood Zewail 
− Construction Engineer: all team members 
• Schedule 
− Need Assessment – 9/15/2010 
− Project Launch – 9/16/2010 
− Project Plan – 9/27/2010 
− Requirements – 10/27/2010 
− Architecture - 11/15/2010 
− Cycle 1 Construction – 12/15/2010 
− Cycle 2 Construction – 1/17/2011 
− Cycle 3 Construction –2/14/2011 
− Cycle 4 Construction –3/24/2011 
− Cycle 5 Construction –4/18/2011 Digital Home Project, SRS 1.3 Page 5 
 
− Cycle 6 Construction –5/16/2011 
− System Testing – 6/20/2011 
− Acceptance Testing – 7/14/2011 
− Postmortem Analysis – 8/1/2011 
 
3. Overall description 
3.1 Product Description and Scope 
The Digital Home system, for the purposes of this document, is a system that will 
allow a home user to manage devices that control the environment of a home. 
The user communicates through a personal web page on the DigitalHome web 
server or on a local home server. The DH web server communicates, through a 
home wireless gateway device, with the sensor and controller devices in the 
home. 
 
The product is based on the Digital Home High Level Requirements Definition 
[HLRD 2010] is intended as a prototype, which will allow business decisions to 
be made about future development of a commercial product. The scope of the 
project will be limited to the management of devices which control temperature, 
humidity, security, and power to small appliances and lighting units, through the 
use of a web-ready device. The prototype DH software system will be situated in 
a simulated environment. There will be no actual physical home and all sensors 
and controllers will be simulated. 
 
3.2 Users Description 
3.2.1 DigitalHome Users 
3.2.1.1 The general user shall be able to use the D H system 
capabilities to monitor and control the environment in his/her 
home. 
3.2.1.2 The general user is familiar with the layou t of his/her home and 
the location of sensor and control devices (for temperature, for 
humidity, and for power to small appliances and lighting units). 
3.2.1.3 Although the general user is not familiar w ith the technical 
features of the DH system, he/she is familiar with the use of a 
web interface and can perform simple web operations (logging 
in and logging out, browsing web pages, and submitting 
information and requests via a web interface). 
3.2.1.4 A Master user will be designated, who shall be able to change 
the configuration of the system. For example, a Master User 
shall be able to add a user account or change the default 
parameter settings. He/she will have the same right as the DH 
Technician, described in section 3.2.2.4. 
3.2.2 DigitalHome Technician Digital Home Project, SRS 1.3 Page 6 
 
3.2.2.1 A DH Technician is responsible for setting up and maintaining 
the configuration of a DH system. 
3.2.2.2 A DH Technician has experience with the typ e of hardware, 
software, and web services associated with a system like the 
DH system. 
3.2.2.3 A DH Technician is specially trained by Dig italHomeOwner to be 
familiar with the functionality, architecture, and operation of the 
DH system product. 
3.2.2.4 A DH Technician will have rights beyond the DH General User, 
capable of setting up and making changes in the configuration 
of the system (e.g.,setting system parameters and establishing 
user accounts), and starting and stopping operation of the DH 
System. 
3.3 Development Constraints 
3.3.1 The “prototype” version of the DigitalHome Sy stem (as specified in this 
document) must be completed within twelve months of inception. 
3.3.2 The development team will consist of five eng ineers. The 
DigitalHomeOwner Director will provide management and 
communication support. 
3.3.3 The development team will use the development process specified by 
the Digital HomeOwner Inc. 
3.3.4 Where possible, the DigitalHome project will employ widely used, 
accepted, and available hardware and software technology and 
standards, both for product elements and for development tools. See 
section 3.4 for additional detail. 
3.3.5 Because of potential market competition for D igitalHome products, the 
cost of DigitalHome elements (sensors, controllers, server, tools, etc.), 
for this project should be minimized. As part of the final project report 
the development team will describe their efforts to minimize costs, 
including price comparisons between DH elements and 
comparable/competitive elements. 
3.3.6 The DH system will be tested in a simulated e nvironment. There will be 
no actual physical home and all sensors and controllers will be 
simulated. However, the simulated environment will be realistic and 
adhere to the physical properties and constraints of an actual home 
and to real sensors and controllers. 
3.3.7 Major changes to this document (e.g., changes in requirements) must 
be approved by the Director of the DigitalHomeOwner Division. 
3.4 Operational Environment 
Although the system to be developed is a “proof of concept” system intended to 
help Homeowner Inc. to make marketing and development decisions, the 
following sections describe operational environment concerns and constraints; Digital Home Project, SRS 1.3 Page 7 
 
some of them are related to issues of long-term production and marketing of a 
DigitalHome product. 
3.4.1 The home system shall require an Internet Ser vice Provider (ISP). The 
ISP should be widely available (cable modem, high speed DSL), such 
as Bright House or Bellsouth FastAccess. 
3.4.2 DH Home Web Server 
3.4.2.1 A DH System shall have the capability to es tablish an individual 
home web server hosted on a home computer. This server will 
provide 
a. Interaction with and control of the DH elements 
b. Storage of DH plans and data. 
c. Ability to establish and maintain DH User Accoun ts 
d. Provide backup service for user account informat ion, user 
plans and a home database 
3.4.3 Home DH Gateway Device 
3.4.3.1 The DH Gateway device shall provide communi cation with all 
the DigitalHome devices and shall connect with a broadband 
Internet connection. 
3.4.3.2 The Gateway shall contain an RF Module, whi ch shall send and 
receive wireless communications between the Gateway and the 
other DigitalHome devices (sensors and controllers).  
3.4.3.3 The Gateway device shall operate up to a 10 00-foot range for 
indoor transmission. 
3.4.4 Sensors and Controllers 
3.4.4.1 The system shall include digital programmab le thermostats, 
which shall be used to monitor and regulate the temperature of 
an enclosed space. 
a. The thermostat shall provide a reading of the cu rrent 
temperature in the space where the thermostat is located. 
b. The controller part of thermostat shall provides a “set point” 
temperature that is used to control the flow of heat energy (by 
switching heating or cooling devices on or off as needed) to 
achieve the set point temperature. 
c. The sensor part of the thermostat has a sensitiv ity range 
between 14oF and 104oF (-10oC and 40oC). 
3.4.4.2 The system shall include digital programmab le humidistats, 
which shall be used to monitor and regulate the humidity of an 
enclosed space. 
a. The humidistat shall provide a reading of the cu rrent humidity 
in the space where the humidistat is located. Digital Home Project, SRS 1.3 Page 8 
 
b. The humidistat shall provide a “set point” humid ity that is used 
to control humidifiers and dehumidifiers achieve the set point 
humidity. 
3.4.4.3 The system shall include magnetic alarm con tact switches 
which shall be used to monitor entry through a door or window 
when the switch is active. 
3.4.4.4 The system shall include security sound and light alarms, which 
can be activated when DigitalHome senses a security breach 
from a magnetic contact. 
3.4.4.5 The system shall include digital programmab le power switches 
which shall be used to monitor the current state of an appliance 
(e.g., a coffee maker is off or on). 
3.4.4.6 The system shall be able to use a power swi tch to change the 
state of the appliance (e.g., from “off” to “on”). 
4. Functional Requirements 
This section provides a description of the functional requirements. There is a DH 
Use Case Model in the Appendix, which provides an overview of the system 
functionality and shows the relationships between the DigitalHome System 
entities. 
4.1 General Requirements 
4.1.1 The DigitalHome System shall allow a web-read y computer, cell phone 
or PDA to control a home's temperature, humidity, lights, security, and 
the state of small appliances. 
4.1.2 The communication center of the DH system sha ll be a DH home web 
server, through which a user shall be able to monitor and control home 
devices and systems. 
4.1.3 Each DigitalHome shall contain a master contr ol device (the DH 
Gateway Device) that connects to the home’s broadband Internet 
connection, and uses wireless communication to send and receive 
communication between the DigitalHome system and the home 
devices and systems. 
4.1.4 The DigitalHome shall be equipped with variou s environmental 
controllers and sensors (temperature controller-sensors: thermostats, 
humidity controller-sensors: humidistats, contact sensors, security 
sound and light alarms, and power switches). 
4.1.5 Using wireless communication, sensor values c an be read and saved 
in the home database. 
4.1.6 Controller values can be sent to controllers to change the DH 
environment. 
4.2 Thermostat Requirements 
4.2.1 The DigitalHome programmable thermostat shall allow a user to Digital Home Project, SRS 1.3 Page 9 
 
monitor and control a home’s temperature from any location, using a 
web ready computer, cell phone, or PDA. 
4.2.1.1 A DH user shall be able to read the tempera ture at a thermostat 
position. 
4.2.1.2 A DH user shall be able to set the thermost at temperatures to 
between 60 ° F and 80 ° F, inclusive, at one degree increments. 
4.2.2 Up to eight thermostats shall be placed in ro oms throughout the home. 
4.2.2.1 The thermostats may be controlled individua lly or collectively, so 
that temperature can be controlled at different levels in different 
home spaces. 
4.2.2.2 A single thermostat shall be placed in an e nclosed space (e.g., 
a room in the house) for which the air temperature is to be 
controlled. 
4.2.2.3 For each thermostat, up to twenty-four one hour settings per 
day for every day of the week can be scheduled. 
4.2.2.4 If a thermostat device allows a user to mak e a manual 
temperature setting, the setting shall remain in effect until the 
end of the planned or default time period, at which time the 
planned or default setting will be used for the next time period. 
4.2.3 A thermostat unit shall communicate, through wireless signals, with the 
master control unit. 
4.2.4 The system shall support Fahrenheit and Celsi us temperature values. 
4.2.5 The system shall be compatible with a central ized HVAC (Heating, 
Ventilation and Air Conditioning) systems: gas, oil, electricity, solar, or 
a combination of two or more. The system shall adhere to the 
standards, policies and procedures of the American Society of Heating, 
Refrigerating and Air-Conditioning Engineers [ASHRAE 2010]. 
4.3 Humidistat Requirements 
4.3.1 The DigitalHome programmable humidistat shall allow a user to 
monitor and control a home’s humidity from any location, using a web 
ready computer, cell phone, or PDA. 
4.3.1.1 A DH user shall be able to read the humidit y at a humidistat 
position. 
4.3.1.2 A DH user shall be able to set the humidity level for a 
humidistat, from 30% to 60%, inclusive a 1% increments. 
4.3.2 Up to eight humidistats shall be placed in ro oms throughout the home. 
4.3.2.1 A single humidistat shall be placed in an e nclosed space (e.g., a 
room in the house) for which the humidity is to be controlled. 
4.3.2.2 If a humdistat device allows a user to make a manual 
temperature setting, the setting shall remain in effect until the Digital Home Project, SRS 1.3 Page 10 
 
end of the planned or default time period, at which time the 
planned or default setting will be used for the next time period. 
4.3.2.3 For each humidistat, up to twenty-four one hour settings per day 
for every day of the week can be scheduled. 
 
4.3.3 A DigitalHome system shall use wireless signa ls to communicate, 
through the master control unit, with the humidistats. 
4.4 Security System Requirements 
4.4.1 The DigitalHome security system consists of c ontact sensors and a set 
security alarms. 
4.4.1.1 A DigitalHome system shall be able to manag e up to fifty door 
and window contact sensors. 
4.4.1.2 A DigitalHome system shall be able to activ ate both light and 
sound alarms: one sound alarm and one light alarm subsystem, 
with multiple lights. 
4.4.2 When a security breach occurs and a contact s ensor is set OPEN, the 
alarm system shall be activated. 
4.5 Appliance Management Requirements 
4.5.1 The DigitalHome programmable Appliance Manage r shall provide for 
management of a home’s small appliances, including lighting units, by 
allowing a user to turn them on or off as desired. 
4.5.2 The Appliance Manager shall be able to manage up to one hundred 
115 volt, 10 amp power switches. 
4.5.3 The system shall be able to provide informat ion about the state of a 
power switch (OFF or ON), indicating the whether an appliance 
connected to the power switch is OFF or ON. 
4.5.4 The system shall be able to change the state of a power switch (OFF 
to ON, or ON to OFF), in turn changing the state of an appliance 
connected to the power switch. 
4.5.5 If a user changes the state of power switch d evice manually, the 
device shall remain in that state until the end of the planned or default 
time period, at which time the planned or default setting will be used for 
the next time period. 
4.6 DH Planning and Reporting Requirements 
4.6.1 DigitalHome Planner shall provide a user with the capability to direct 
the system to set various preset home parameters (temperature, 
humidity, security contacts, and on/off appliance/light status) for certain 
time periods. 
4.6.2 DigitalHome provides a monthly planner. 
4.6.2.1 For a given month and year, a user shall be able to create or Digital Home Project, SRS 1.3 Page 11 
 
modify a month plan that specifies for each day, for up to four 
daily time periods, the environmental parameter settings 
(temperature, humidity, contact sensors and power switches). 
4.6.2.2 A user shall be able to override planned pa rameter values, 
through the DH website, or if available, through manual 
switches on household devices 
4.6.3 For a given month and year, in the past two y ears, DigitalHome shall 
be able to provide a report on the management and control of the 
home. 
4.6.3.1 The month report shall contain daily averag e, maximum (with 
time) and minimum (with time) values of temperature and 
humidity for each thermostat and humidistat, respectively. 
4.6.3.2 The month report shall provide the day and time for which any 
security breaches occurred, that is, when the security alarms 
were activated. 
4.6.3.3 The month report shall provide a section th at indicates the 
periods of time when the DH System was not in operation.. 
5. Other Non-Functional Requirements 
5.1 Performance Requirements 
5.1.1 Displays of environmental conditions (tempera ture, humidity, contact 
sensors and power switches) shall be updated at least every two 
seconds. 
5.1.2 Sensor (temperature, humidity, contact sensor , power state) shall have 
a minimum data acquisition rate of 10 Hz. 
5.1.3 An environmental sensor or controller device shall have to be within 
1000 feet of the master control device, in order to be in communication 
with the system. 
5.2 Reliability 
5.2.1 The DigitalHome System must be highly reliabl e with no more than 1 
failure per 10,000 hours of operation. 
5.2.2 The Digital Home System shall incorporate bac kup and recovery 
mechanisms. 
5.2.2.1 The DH System will backup all system data ( configuration, 
default parameter settings, planning, and usage data) on a daily 
basis, with the backup time set by the DH Technician at system 
set up. 
5.2.2.2 If the DH System fails (due to power loss, loss of internet 
access, or other software or hardware failure), the system 
recovery mechanism shall restore system data (configuration, 
default parameter settings, planning, and usage data) from the 
most recent backup. Digital Home Project, SRS 1.3 Page 12 
 
5.2.3 All DigitalHome operations shall incorporate exception handling so that 
the system responds to a user with a clear, descriptive message when 
an error or an exceptional condition occurs. 
5.3 Safety Requirements 
5.3.1 Although there are no specific safety require ments, high system 
reliability is important to insure there are no system failures in carrying 
out user requests. Such failures might affect the safety of home 
dwellers (e.g., security breaches, inadequate lighting in dark spaces, 
inappropriate temperature and humidity for people who are in ill-health, 
or powering certain appliances when young children are present). 
5.4 Security Requirements 
5.4.1 Upon installation, a DigitalHome user account shall be established. 
The DigitalHome web system shall provide for authentication and 
information encryption through a recognized reliable and effective 
security technology, such as Transport Layer Security. 
5.4.2 Log in to an account shall require entry of a n account name and a 
password. 
5.5 Maintenance Requirements 
5.5.1 The development of the DH system shall use me thods and techniques 
such as the following to support system maintenance: 
5.5.1.1 Documentation of requirements, design, and code 
5.5.1.2 Use of abstraction, information hiding and module 
independence in system design; and 
5.5.1.3 Use of IEEE standards [IEEE830, IEEE1008, I EEE1016, 
IEEE1028] and the HomeOwner Coding Standard [HO4710]. 
5.5.2 Although the product produced under this docu ment will be a 
“prototype” version, all modules and components of this prototype 
version shall be designed and implemented in such a manner that it 
may be incorporated in a fully specified commercial version of the 
DigitalHome System. 
5.6 Business Rules 
5.6.1 All system documents (Software Requirements S pecification, 
Architectural Design Specification, Module Detailed Design, Module 
Source Code, and all Test Plans) shall be up-to-date, use the 
Homeowner document format [HO2305] and reside in the HomeOwner 
Document Archive at completion of the project. 
5.6.2 HomeOwner has designated object-oriented deve lopment, using UML 
2.0, as the preferred method for development of software for 
HomeOwner products. Exceptions to this rule must be approved by the 
CIO. Digital Home Project, SRS 1.3 Page 13 
 
5.7 User Documentation: 
5.7.1 The DigitalHome System shall provide users wi th online 
documentation about the DigitalHome system installed in their home. 
The user documentation shall include the following: 
5.7.1.1 An FAQ section – a set of “Frequently Asked Questions” about 
use and maintenance of the DigitalHome System (e.g., “How do 
I change my password?”, “Where to I go to get Digit alHome 
support?”). 
5.7.1.2 A section that explains how DH parameters a re set and sensor 
values are read. This shall include information on limitations and 
constraints on parameter settings and sensor reading accuracy. 
5.7.1.3 A section that describes how to use the DH Planner. 
 
 Digital Home Project, SRS 1.3 Page 14 
 
6. Glossary 
ASHRAE - American Society of Heating, Refrigerating and Air-Conditioning 
Engineers 
 
Authentication 
 - any process by which it is verified that someone is who they 
claim they are. This typically involves submission and verification of a username 
and a password. 
 
Broadband Internet 
 - a high data rate Internet access, typically contrasted with 
slower dial-up access 
 
DH (Digital Home) 
 - the name of the prototype smart home product that is be 
produced by DigitalHomeOwner 
 
DigitalHomeOwner 
 – the division of HomeOwner Inc. responsible for p roducing 
DigitalHome products 
 
DSL (Digital Subscriber Line) 
 - a family of technologies that provides digital data 
transmission over the wires of a local telephone network 
 
Encryption 
 - the process of transforming information (referred to as plaintext) 
using an algorithm (called cipher) to make it unreadable to anyone except those 
possessing special knowledge, usually referred to as a key. 
 
FAQ 
 – frequently asked question 
 
Gateway Device 
 - a home networking device used to connect devices in the 
home to the Internet or other Wide Area Networks. 
 
HomeOwner Inc. 
 - the largest national retail chain serving the needs of home 
owners in building, furnishing, repairing, and improving their homes 
 
HVAC 
 - Heating, Ventilation and Air Conditioning 
 
Humidistat 
 - an instrument that measures and controls relative humidity 
 
ISP 
 -Internet Service Provider 
 
PDA 
– Personal Digital Assistant 
 
RF 
 – Radio Frequency 
 
Security Breach 
 – an external act that bypasses or contravenes the digital home 
security system. For example, if an intruder opens a door where the contact 
sensor is set to “on”, the system will sense a ‘security breach”. 
 Digital Home Project, SRS 1.3 Page 15 
 
Set Point – a numeric valuable that establishes the desire v alue of an 
environmental quality (e.g., a temperature value of 70° F 
 
SRS 
 – Software Requirements Specification 
 
Transport Layer Security 
 - cryptographic protocols that provide security for 
communications over networks such as the Internet 
 
7. References 
[ASHRAE 2010] Website for American Society of Heating, Refrigerating and Air-
Conditioning Engineers, accessed October 2010, 
http://www.ashrae.org/ . 
[HLRD 2010] DigitalHomeOwner Division, Digital Home High Level 
Requirements Definition , Homeowner Inc., September 2010. 
[HO2305] Sykes, J., and Rook, R., Guidelines for Developing HomeOwner 
Technical Reports , HO2305., Homeowner Inc., March 2002. 
[HO4710] Kramer, S., HomeOwner Coding Standard , HO4710.,Homeowner Inc., 
August 2009. 
[HO2010] Digital Home Use Case Model , HomeOwner Inc, DigitalHomeOwner 
Division, October 24, 2010. 
[IEEE830] IEEE Std 830-1998, IEEE Recommended Practice for Software 
Requirements Specifications , Institute of Electrical and Electronics Engineers, 
Inc., 1998. 
[IEEE 1008] ANSI/IEEE Std 1008-1987, IEEE Standard for Software Unit 
Testing , Institute of Electrical and Electronics Engineers, Inc., 1987. 
[IEEE 1012] IEEE Std 1012-2004, IEEE Standard for Software Verification and 
Validation , Institute of Electrical and Electronics Engineers, Inc., 2004. 
[IEEE1016] IEEE Std 1016-2009, IEEE Standard for Information Technology - 
Systems Design - Software Design Descriptions , Institute of Electrical and 
Electronics Engineers, Inc., 2009. 
[IEEE1028] IEEE Std 1028-2008, IEEE Standard for Software Reviews and 
Audits, Institute of Electrical and Electronics Engineers, Inc., 2008. 
[Meyer 2004] Meyer, G., Smart Home Hacks: Tips & Tools for Automating Your 
House, O’Reilly, 2004. 