Software Requirement Specification for Facebook

Software Requirement

Specification for Facebook

April 2011, Ankara

Prepared by

Fulya Terzi

Gökhan Ceyhan

Onur Yılmaz

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Table of Contents

1. Introduction 5

1.1 Purpose 5

1.2 Scope 5

1.3 Definitions, Acronyms And Abbreviations 6

2. Overall Description 6

2.1 Product Perspective 6

2.2 Product Functions 7

2.3 User Characteristics 7

2.4 Constraints 7

3. Specific Requirements 8

3.1 External Interface Requirements 8

3.1.1 User’s Interfaces 8

3.1.1.1 Standard User Interface 8

3.1.1.2 Facebook Administration Interface 13

3.1.2 Communication Interfaces 15

3.2 System Features 15

3.2.1 Creating An Event 16

3.2.1.1 Background Information 16

3.2.1.2 Stimulus/Response Sequence 16

3.2.1.2.1 Diagram 16

3.2.1.2.2 Description 17

3.2.1.2.3 Normal Flow Of Events 17

3.2.1.2.4 Alternative Flow Of Events 17

3.2.1.3 Functional Requirements 17

3.2.2 Attending An Event 18


3.2.2.2 Stimulus/Response Sequences 18

3.2.2.2.1 Diagram 18




3.2.3 Searching Friends 19



3.2.3.2.1 Diagram 20




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3.2.4 Adding Friends 22



3.2.4.2.1 Diagram 22




3.2.5 Creating Groups 23



3.2.5.2.1 Diagram 24




3.2.6 Uploading Photos 25


3.2.6.2 Stimulus/ Response Sequence 26

3.2.6.2.1 Diagram 26




3.2.7 Creating Albums 27



3.2.7.2.1 Diagram 27




3.2.8 Sharing User Status 28



3.2.8.2.1 Diagram 29





3.2.9 Sending Messages 30


3.2.9.2 Stimulus / Response Sequences 31

3.2.9.2.1 Diagram 31



3.2.9.2.4 Alternative Event Flows 32


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3.2.10 Receiving Messages 34



3.2.10.2.1 Diagram 34





3.2.11 Commenting 36



3.2.11.2.1 Diagram 36




3.2.12 Uploading Videos 37



3.2.12.2.1 Diagram 38





3.2.13 Creating Complaint Reports 39



3.2.13.2.1 Diagram 40





3.2.14 Reading Complaints 41



3.2.14.2.1 Diagram 42




3.2.15 Responding Complaints 44



3.2.15.2.1 Diagram 44




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4. Non-Functional Requirements 46

4.1 Performance Requirements 46

4.2 Design Requirements 46

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1. INTRODUCTION

This document is prepared in order to determine a software requirement specification

for Facebook. Facebook is a social network on which people can add their friends, share

videos and photos, send and receive messages, comment on the links etc. In order to gain an

overview about the report, firstly, the purpose and scope of this document will be given, then

an overall description of Facebook system is followed. In addition to these, system features

such as uploading photo, sharing video, adding friend etc. are described deeply. After

mentioning about the introduction of the software system, the specific requirements will be

addressed for it. In the final part, functional and non-functional requirements will be

addressed.

1.1 PURPOSE

The SRS is needed to evolve as the development of the software product processes.

The purpose of this document is to give a complete description about how Facebook social

network system can be developed. This document is to provide information about what the

software product is to do to customers and establish an agreement between customers and

suppliers and also become helpful for development. In addition to these, it provide a basis for

validation and verification. The issues which are basically addressed are functionality such as

adding friends, uploading photos, external interfaces, performance, attributes and the design

constraints of the system.

1.2 SCOPE

The name of the software product is Facebook. Facebook is a social network that

connects people. The aim of Facebook is to provide information to the users about the events

and the people whom they know. The users of Facebook can add friends, share videos which

they want their friends watch; upload photos, comment on their friends’ sharings, chatting

with their friends and become informed about their friends. Moreover, people can create

social groups for such as university clubs, football clubs or for social awareness. People can

be informed about the events by the help of these groups or their friends.

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1.3 DEFINITIONS, ACRONYMS and ABBREVIATIONS

When the user logins Facebook, they can see their home page, which is named as

“News Feed” that provide users to see what their friends share, what their friends write their

status. Moreover, at the left of this page, the user can see the event invitations and the

birthdays of their friends. Therefore News Feed is the main page which combines daily friend

interactions.

2. OVERALL DESCRIPTION

In this section, background information about what type of requirements the system

should have will be provided briefly.

2.1 PRODUCT PERSPECTIVE

Facebook is an independent and world-wide social network website. Every person can

use it online without a fee. The Facebook is not a part of a larger system, it is an independent

system. People from different regions of the world can connect to it and exchange information

with other people. In order to control the contents of the sharings and comments done by the

other people, Facebook has also a control mechanism. People can deliver their complaints

about any part of the Facebook to the “Facebook Administrators”. Then, “Facebook

Administrators” might take appropriate actions according to the complained situation which is

against the rules.

Figure 2.1.1: Facebook social network website system

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2.2 PRODUCT FUNCTIONS

After creating an account and starting to use the Facebook, first thing he or she will

make is searching for friends. The user will search people by their names and can send an

invitation to them to add as a friend and to be able to see their shared items on Facebook. If

the person accepts the invitation, these two persons become friends on Facebook and can

interact more closely such as sending messages to each other.

Any user can share his/her status like whatever he is thinking, wherever he is or his

current mode. Friends of this person can make a comment on that. Furthermore, if a user

shared a photo, video, link or anything, any friend of that user can share that shared item also.

Users can upload photo and video to their profiles and create an album. Anyone can

create a group and invite people to join in the group. Similarly, people can attend the activities

where they are invited.

2.3 USER CHARACTERISTICS

Facebook does not require any specific computer knowledge to use it except the

developers and administrators of it. Standard users are thought to be from any age, any gender

and from any nationality who can use just computer’s browser. On the other hand,

administrators and potential developers need a high level of expertise to understand web

technologies.

2.4 CONSTRAINTS

Being a social network website, the software should ensure the safety of information

given by the user and provide some privacy settings options to the user.

Firstly, Facebook provides people the right to choose the category of people who will

be able to view their shared items. Some users may not desire the access of some people to

their shared items and information. If this is the case, users can set their privacy settings to

prevent some people’s access to their information.

Secondly, Facebook cannot sell the private information of users to someone else.

However, if the user permits, an application can access to some information of the user.

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3. SPECIFIC REQUIREMENTS

In this section, all software requirements will be explained in detail. All requirements

are divided into two groups as functional and non-functional.

3.1 EXTERNAL INTERFACE REQUIREMENTS

In this section, external interface requirements for user and communication channels

will be described in order to clarify the relationship of this software with other entities and

systems.

In the first part, user’s interfaces will be explained with the layout information, textual

items and error handling types for two types of users of the system, as standard users and

Facebook administrators. In the second part, communication interfaces of our system will be

described in order to explain the relationship with other systems which are sharing

information with Facebook.

3.1.1 USER’S INTERFACES

3.1.1.1 STANDARD USER INTERFACE

Standard users shall be using the web browser to use the product. Thus, it shall have a

login page and users must login with their e-mail addresses and passwords. After a successful

login, they shall be taken to their “News Feed” which is their homepage thereafter. Since they

are logged into the system, there must be logout button and their Facebook profile names at

the top of the page until they logged out of the system. In addition, there shall be Help menu

in order to explain the processes of Facebook to the users.

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Figure 3.1.1.1: Diagram for Standard User Interface of Facebook

Being a social network, a direct link to the list of “Friends” shall be listed in the

“Account” menu, located at the right top, which shall also include “Logout” and “Account

and Privacy Settings”. At the top, there shall be “Home” and “Profile” buttons which are used

for linking News Feed and users’ own profile respectively. “Search” field which lets users

search for their friends, events, etc. shall be located at the center of the top in the whole

processes. All other features of the system shall be reachable by menu as a left sidebar such as

Events, Photos, Videos, Groups etc. In the menu, order of these features shall be updated

according to their usage levels for the users Finally, sub-functions, such as “Creating Event”

which is related to “Events” feature, shall be reachable from the related features menu.

Since standard users can use different types of features, there shall be different

interfaces for each of them and they will be described separately:

a) Creating an Event:

This function’s interface will be a form which contains text fields/areas and check

boxes. This form will have a “text fields” for “Date and Time”, “Name” and “Place” of the

event. Optional text fields for ending time will be shown when user clicks on “Adding End

Time” and optional “Street” and “City/Town” will be shown when user clicks on “Adding

Street Address” button. There will be a “text area” which is for “Additional Information”.

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There will be a button for selecting guests and when user clicks on this, friends list will be

shown to select. Finally there will be two check boxes for making event “Public Event” and

“Showing guest list to others”. In order to send this form, there will be a “Create Event”

button. If the user does not fill the form correctly, s/he will be notified and when the user

submits correctly s/he will be directed to Event page which is just created.

Attending an Event:

This function will be shown in the related event’s page at the top of the page. This will

be formed of three buttons for attendance situation of the user to the event. These shall be

“No”, “Yes” and “Maybe Attending”. When user clicks on “Yes” or “Maybe Attending”, s/he

will be listed in the guest list and when “No” is clicked no action will be taken.

b) Uploading Photo:

When this function is to be performed, there will be a button for choosing image files.

When user clicks on it, a file browser will be opened to select images. When user successfully

uploads the photo, s/he will get a notified, if an error occurs during the upload, the user bill be

informed about it.

c) Creating Album:

This function will have an interface as a form type. This form will include two text

fields for “Name of the Album” and “Location” and there will be a drop down menu for

selecting the album’s privacy settings. In order to complete form, there will be Cancel and

Create Album buttons. When user creates album s/he will be taken to uploading photo

function.

d) Uploading Video:

With resembling to Uploading Photo interface this function will have a button for

choosing files to be uploaded and there will be a text field for the name of the video. In

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addition, limit and copyright notifications will be shown (under 1024 MB and 20 minutes and

user’s own production). If user selects inappropriate files, s/he will be informed, on the other

hand successful uploading will take the user to the video page which is just uploaded.

e) Sending Message:

This function will use an interface constituted of one text field for message receiver

and one text area for message itself. There will be two buttons for attaching a file or picture

and one additional check box if the user wants this message to be sent as a text message also.

To complete form, there will be send and cancel buttons. Upon successful sending user will

be informed as “your message sent” and if no user selected or no message is written send

button will not take any action and no notification will be shown.

f) Receiving Message:

This function will be available through the “message received notification” in the

home page. Reaching the receiving message interface, the sent message will be shown with

the sender’s “Profile Name” and “Profile Picture”. Time at the message sent will be shown at

the right top of the message and subject of the message will be shown below time. In order to

continue conservation, at the bottom there will be Sending Message interface.

g) Sharing User Status:

For this function, there will be a text field for the status to be shared and there will be a

drop down menu for selecting the privacy level of the shared status for Friends, Networks or

Public. Finally, there will be a share button to complete the form. When the user exceeds the

limit of status, which is 420 characters, s/he will be informed for “Exceeding limit”; therefore

the remaining character limit will be shown at the right top of the text area. Upon sharing in

the limits, the shared status will be shown in the News Feed thereafter.

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h) Commenting:

This function will be reachable for the every shared item such as pictures, videos, user

status etc. This interface will have a text area for comments and when the user presses “Enter”

key after writing the comment in the text field, the comment will be listed thereafter in the

bottom of the related item.

i) Searching Friend:

This interface will be reachable from every page and will include one text field for text

to be searched and one button at the left to start searching. This interface will take the user to

the results page which shows the list of the search results.

j) Adding Friend:

This function will be reachable from every profile page which is not already added as

a friend. Clicking the “Add as a Friend” button from the top of the profile page, interface of

this function will be reached. This interface will have an optional button for adding “Personal

Message” to the other user which will open a text field for this personal message. At the right

bottom of the interface, there will be two buttons for cancelling the request and sending the

request. Sending the request successfully, an informative text will be shown at the profile

page of the user which the request sent as “a friendship request sent” instead of “Add as a

Friend” button thereafter.

k) Creating Group:

This interface will be in a form style. There will be a text field for the group name and

a text area for writing the names of the group members. At the bottom of the interface, a drop-

down menu will help user to select the privacy level of the group and these will be followed

by create and cancel buttons. If the user either does not type a group name or any friend’s

name to be member of the group, the user will be informed. When the user successfully fills

fields, the interface will take the user to the group page which is just created.

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l) Creating Complaint:

This interface will be reachable from any of the profile pages, shared items or events

by clicking a direct link. This interface will be in a form style which lets users to select any of

the reasons why they are complaining about the content. Therefore the reasons will be listed

with radio boxes. In order to send the complain report, there shall be “Continue” and “Cancel”

buttons. Upon successful sending the user will be informed about the completion.

3.1.1.2 FACEBOOK ADMINISTRATION INTERFACE

Administrators of the Facebook will be using the administration features by logging

into their specific interface using a browser. Therefore, there shall be a login page which is

different than standard users’ login page and administrators shall use that page to login

system. After successful login they will be taken to the reading complaints interface directly.

In addition, administrator’s name, authority level and logout button shall be located at the top

of the page thereafter. Basic outline for the Facebook administrators’ interface can be seen the

figure below 3.1.1.2:

Figure 3.1.1.2: Diagram for Interface of Facebook Administrators

Administrators’ main responsibility will be reading and responding complaints,

however they will be able to search through Facebook users and send message to them in

order to control activities of users that have complaints recorded against. Therefore, after a

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successful login, administrators will be able to reach sending messages, searching, reading

and responding complaints interfaces by the direct links given at the top of the page.

Since searching and sending message interfaces are same as the standard users’

interfaces, they will not be described again in this part. On the other hand, Reading

Complaints and Responding Complaints interfaces will have different characteristics that will

be described as following:

a) Reading Complaints:

This interface will enable administrators to read the complaints that are sent.

Therefore, this interface will be in a list type which includes subject of the complaint, name of

the sender, content of the complaint and time when the complaint is sent. Administrator will

be able to sort the complaints according to their priority levels or to time at which the

complaint is occurred; therefore, at the top of the list related buttons shall be located. In

addition, administrator will be able to filter the complaints according to the time interval that

are sent, countries which they are sent from and priority levels. Therefore, drop down menus

for filtering functions must be located next to the list.

b) Responding Complaints:

This interface will enable administrators to take actions to the complaints that are sent.

Therefore this interface shall be shown at the bottom of the complaint which is related to.

These actions will include deleting the user account, sending an attention to the user and

deleting the shared item which does not obey copyright or privacy rules. Therefore, a drop

down menu in order to let the administrator to select an action shall be located. After taking a

successful action, or in this concept responding the complaint, a feedback will be given to the

administrator.

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3.1.2 COMMUNICATION INTERFACES

As a whole social networking website, Facebook will be completely stand-alone

system which lets other platforms connect, fetch and transform data in certain levels.

Therefore, other platforms such as mobile phone applications, namely Facebook for Android,

iPhone, Windows Mobile etc., or other websites which want to use Facebook integration will

be connecting to the Facebook main system by using Facebook Platform. Facebook Platform

will provide APIs and tools to 3rd party developers to let them create high-level integrated

plugins and programs. Therefore main communication interface with the other platforms will

be Facebook Platform for Facebook. However, this integration and its level will be set by the

user, who wants to integrate their accounts and information with other websites. Basic outline

of the communication interfaces could be seen from the figure 3.1.2 below:

Figure 3.1.2: Communication Interfaces

3.2 SYSTEM FEATURES

In this section, all normal and alternative flow of events are organized with the

assumption that users or administrators are successfully reached their homepage by loginning

to the system. This assumption is made in order to describe specifications of the sub-features

with better focusing.

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3.2.1 CREATING AN EVENT

3.2.1.1 Background Information

Facebook is a social network site so people want also to use Facebook in order to

inform their friends and other people who are friends of their friends about activities and

events. For this reason, Facebook provides users such a system feature. On the right hand side

of the screen, there is a link that opens the events page and at the left hand side of this events

page, there is a box which link to create an event.

3.2.1.2 Stimulus/Response Sequence

3.2.1.2.1 Diagram

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3.2.1.2.2 Description

Primary Actor Standard User

Goal in context The purpose of this feature is to enable users to create an event for

informing their friends about their activities.

Preconditions In order to create an event, people must have a Facebook account.

Trigger User wants to create an event, which they want to make in real life,

in online manner.

3.2.1.2.3 Normal Flow of Events

1. User reaches the events interface from the homepage of Facebook.

2. The necessary information is typed the required areas.

3. User clicks create an event to finish creating.

4. User is notified of the successful operation she has performed.

3.2.1.2.4 Alternative Flow of Events

Alternative Event Flow 1:

3. User presses create event button without completing the name of the event.

4. User is notified that s/he must provide an event name.


3. User presses create event button without filling the time of the event.

4. User is notified that s/he must provide an event time.

3.2.1.3 Functional Requirements

REQ. 1: System shall check whether the name of the event is entered.

REQ. 2: System shall check whether the time of the event is entered.

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3.2.2 ATTENDING AN EVENT


The created events can be sent to the people in user’s friend list in order to inform

them about the event and ask whether they attend or not. The users, who are sent event

request, can learn the details of the event and attend this event. After attending an event in

online manner, they can learn any change in the event schedule, place or content.

3.2.2.2 Stimulus/Response Sequences

3.2.2.2.1 Diagram



Goal in context The purpose of this function is to enable the user to attend events in

the online manner and inform people about the changes.

Preconditions There must be a created event in order to attend.

Trigger User wants to attend and be informed about the events.

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1. User reaches the event invitation interface from the homepage of Facebook.

2. User presses I’m attending button.

3. The page is renewed and the user added to attending list.


2. User does not respond the event invitation.

3. The event invitation is removed automatically when the event time is finished.

3.2.3 SEARCHING FRIENDS


Since Facebook is introduced to people as a social network, searching friends is one of

the main features of Facebook. This function of the system enable the users find their friends

by searching with their friends’ name. If the searched friend is Facebook user and s/he do not

close their profile to searches from privacy settings, the search engine of Facebook will come

out the people who has the searched name.

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3.2.3.2.1 Diagram



Goal in context The purpose of the feature is to help people find their friends.

Preconditions The typed names must be similar with the account names of the their

friends.

Trigger User wants to find their friends in order to communicate.


1. User reaches searching friend interface from every page.

2. User types the name of his/her friend in the search box.

3. The results are shown on the screen.

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2. User typed a name that is not a name of the user of Facebook.

3. User is notified of the no results.


REQ. 3: System shall not view the users who do not want to show themselves at

search results.

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3.2.4 ADDING FRIENDS


The users can add their friends from search results or from the name of their friends

that is listed as “people who you may know” part of the homepage. After reaching the

interface, the user can send request to his/her friend by clicking the “Add as Friend” button. If

the friend accepts the friend request by clicking accept option, the friend is added to friend

list.


3.2.4.2.1 Diagram

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Goal in context The purpose of the feature is to enable the users to add their friends

into their friends list.

Preconditions The friend must allow other people to add herself/himself as a

friend.

Trigger User wants to add his friend to friend list to follow and communicate

his friend.


1. User reaches the profile page of her friend whom s/he want to add.

2. User presses add as friend button.

3. User is notified of the friend request is sent.


REQ. 4: If the other user has set privacy level to prevent others adding as a friend, system

shall not let other users add as friend.

3.2.5 CREATING GROUPS


The users can create groups for common shared view, activity or information. At the

left hand side of the screen, there is create group link. The users can create groups by clicking

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this link. They must name the group; add their friends who they want to member of the group

and must be select privacy feature when they create a group. After the creation, the admin can

send to request to others to join the group.


3.2.5.2.1 Diagram



Goal in context The purpose of this feature is to enable to users create groups in

online manner and share posts with group members.

Trigger User wants to create a group to share information and collaborate.


1. User reaches the create group interface from the homepage of Facebook.

2. The necessary information is typed the required areas.

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3. User presses the “Create an event” button.

4. User is notified of the successful operation s/he has performed.


3 User presses create button without completing the group name.

4. User is notified that s/he must write a group name.

3.2.6 UPLOADING PHOTOS


In order to upload a photo in a already created album or upload photo without having

an existing album, the user should click on the profile tab on the right top of the Facebook

page. Then, if the user wants to add a photo to an album, the user should choose the album

first and then the photo from the file browser. If the user does not want to upload a photo to

existing albums, then an album has to be created first.

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3.2.6.2 Stimulus/ Response Sequence

3.2.6.2.1 Diagram


Primary Actor Standard user

Goal in context The aim of the user is to upload a photo on his/her profile and

make his/her friends see it.

Preconditions User has to have an created album.

Trigger User wants to upload a photo to an album.


1. User clicks the profile tab and sees the already created albums.

2. User clicks the album where he wants to add a photo.

3. User chooses the photo from the file browser and marks one of the quality options

in the radio box.

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4. If the user desired, s/he can tag his friends in the photo.

5. User is notified that s/he successfully uploaded the photo.


1. When the user wants to upload photo without choosing an album, album creation

form is opened.

3.2.7 CREATING ALBUMS


When the user wants to create an album on his profile, a form type interface will

appear with fields or “Name of the Album” and “Location”. In addition to these, there will be

a quality of the photos option and a drop down list to choose the group with whom the album

will be shared. After this step, the user will be directed to photo uploading feature. Finally, the

user can click on create the album or cancel option.


3.2.7.2.1 Diagram

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Goal in context The aim of the user is to create an album on his profile and

make his friends see it.

Preconditions The user should be logged in.

Trigger User wants to create an album.


1. User reaches the album creation form.

2. User fills the required fields.

3. Photo uploading stage takes place.

4. User chooses create album and completes creation.


4. If the user clicks on the cancel at the end of the process, a warning box will

appear asking for user’s approval.

3.2.8 SHARING USER STATUS


At the top of the news feed part of the Facebook page, there will be a part for user

status. This part will be consisting of four different type of sharing. The user can only text

whatever he wants or share a photo, url or a video. The user can select the privacy level of the

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shared status for Friends, Networks or Public as well. There is a limit for status text which is

420 characters. If the user exceeds it, a notification message will be appeared. After, creating

the status, the status will be shown on the news feed after clicking on the share button. Other

user can click on the “like” the sharing as well.


3.2.8.2.1 Diagram



Goal in context The aim of the user is to share her/his current status.


Trigger User wants to share an item on the news feed.


1. User shares text less than 420 characters, url, photo or a video.

2. User sets the privacy settings and clicks on the share button.

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3. Status is shown on the news feed.


1. User exceeds the limit and gets an error message.


REQ. 5: A user can like the sharing if he/she is included in the group specified in the

privacy settings by the user who shared the status.

REQ. 6: System shall check whether the size of the status is less than 420 characters.

3.2.9 SENDING MESSAGES


Being a social network, Facebook will enable users to send messages to each other.

Sending message interface will be available from messages menu in the homepage and this

will let users to send messages to their friends. In addition, there will be direct links at the

profile pages, which lets users send messages to the profile owner they are visiting, therefore

users will be able to send messages to the people that are not their friends.

Sending message will include filling a text area and optionally attaching images or any

other kind of files to the messages. In addition, sender will be able to choose to send the same

message as an SMS message to the receiver, if the receiver is a friend of sender in the

Facebook.

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3.2.9.2 Stimulus / Response Sequences

3.2.9.2.1 Diagram



Goal in context The purpose of this feature is to send messages, optionally with

attachments, to the other users, which are already their friends or not.

Preconditions Receiver should have set her/his privacy level to receive messages from

other users.

Trigger User wants to send a message to the other user.


1. User reaches the sending message interface from the homepage of Facebook.

2. User chooses a friend’s name by writing it.

3. User types the message s/he wants to send.

4. User clicks send button.

5. Sending message interface closes after the notification that the message is

sent.

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3.2.9.2.4 Alternative Event Flows

Alternative Event Flow 1 (Related to Normal Flow of Events and Alternative

Event Flow 6):

4. User clicks attachments button.

5. File browser opens to let user select files.

6. User selects files.

7. Selected files are uploaded.



sent.

Alternative Event Flow 2 (Related to Alternative Event Flow 1):

6. User selects inappropriate types of files, such as system files and executable

files.

7. User is informed that these kinds of files cannot be sent as attachments.

Alternative Event Flow 3 (Related to Alternative Event Flow 1)

6. User exceeds the attachments size limit, which is 25 megabytes.

7. User is informed that the total size of attachments is exceeded.

Alternative Event Flow 4 (Related to Normal Flow of Events)

5. User exceeds the message length limit, which is 10000 characters including

spaces.

6. User is informed that the message is too long.

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4.User checks send as an SMS option.



sent.


1. User reaches the sending message interface from the receiver’s profile page.

2. User types the message s/he wants to send.



sent.


REQ. 7: System shall check whether the receiver allows receiving messages.

REQ. 8: System shall check whether sender and receiver are friends to allow sending by

SMS.

REQ. 9: System shall check the file types of attachments to prevent misuse of messages.

REQ 10: System shall check the size of the attachments, whether total size of attachments is

less than 25 MB.

REQ 11: System shall check the length of the message, whether it is longer than 10000

characters.

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3.2.10 RECEIVING MESSAGES


This feature will enable standard users to receive the messages that are sent to them. Using

this feature, users will be able to see the list of the messages that are sent to them with the subject of

the message, sender’s name and picture. In addition, time the message sent will be shown and

messages will be listed from the newest to the oldest message. Since this list will contain both read

and unread messages, unread messages will be notified in the list view.


3.2.10.2.1 Diagram



Goal in context The purpose of this feature is to convey the messages that are sent to

user by correctly listing the archive of sent messages.

Preconditions The primary actor should be able to receive messages according to

his/her privacy settings.

Trigger Being notified about unread messages or not, the user wants to read

the messages that are sent.

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1. User reaches the messages interface from the homepage of Facebook.

2. User clicks an unread message that is listed.

3. Message content is fully shown to the user and unread sign is removed from the

message.

4. User leaves receiving message interface.



2. User clicks an already read message that is listed.

3. Message content is fully shown to the user.



4. User writes a reply through Sending Message interface shown in the bottom of the

message that is received.

5. Sending Message feature event flow is followed.



REQ. 12: System shall view the messages only that are sent to the user.

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3.2.11 COMMENTING


This feature will enable standard users to comment on the shared items on the Facebook.

Commenting will be done by an interface of a text field located at the bottom of every shared item

throughout the Facebook. This feature and the interface will be available only on the friends’ shared

items; however comments will be shown to the every user who could see the shared item.


3.2.11.2.1 Diagram



Goal in context The purpose of this feature is to enable users to share their ideas on

the shared items all over the Facebook.

Preconditions Primary actor must be the friend of the other user in order to comment

on the other user’s shared item.

Trigger The user wants to comment on the other friends’ shared item.

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1. User reaches commenting interface from any shared item.

2. User types the comment into the text field.

3. User presses enter.

4. Written comment is shown thereafter and new comment interface is located under

that comment.

5. User leaves commenting interface.


REQ.13: System shall view commenting interface only for the friend’s shared items.

3.2.12 UPLOADING VIDEOS


Uploading video includes similar steps with uploading a photo. The user should click

on his profile and then upload video button. Then, the file browser will be opened and the user

can select the video from there. However, the video must be less then 20 minutes or 1024 MB

and it has to be user’s own production, not a copyrighted video. In case of inappropriate files,

the user will be notified. If it is successfully uploaded, the user will be directed to the page

where the video is uploaded.

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3.2.8.2.1 Diagram



Goal in context The aim of the user is to upload a video.


Trigger User wants to upload a video on his profile.


1. User chooses a video less than 20 minutes or 1024 MB and not a copyrighted video

from the file browser.

2. User clicks on the upload button.

3. The video is uploaded to profile page.

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Alternative Flow 1:

1. User exceeds the limit and notified about unsuccessful operation.

Alternative Flow 2:

1. User chooses a copyrighted video and notified about unsuccessful operation.

Alternative Flow 2:

1. User chooses an unsupported video format. An error box with a list of supported

video format will be appeared.

2.


REQ. 14: System shall check whether the size of the video is less than 20 minutes or 1024

MB .

REQ. 15: System shall check whether the video is copyrighted or not.

REQ. 16: System should support all the video formats of the other platforms that are

connected to Facebook.

3.2.13 CREATING COMPLAINT REPORTS


This feature will enable standard users to report their complaints to the Facebook

administrators, which is the only controlling mechanism of this social network. Standard users will be

able to report copyright issues, harassment, inappropriate profile pictures and posts (shared items)

therefore this feature will be reachable from any part of Facebook. After selecting appropriate reasons

from the creating complaints interface, report will be sent to the database and user will be informed

that complaint is successfully sent.

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3.2.13.2.1 Diagram



Goal in context The purpose of this feature is to enable users to report inappropriate

use of Facebook.

Preconditions The profile or the item about which the complaint will be reported,

should not have any unresolved complaints.

Trigger The user wants to report a complaint about any item or the profile in

the Facebook


1. User reaches creating complaint interface from any shared item or profile page.

2. User selects any one of the reasons.

3. User clicks continue button.

4. User is notified about successful report sending.

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5. User leaves commenting interface.



2. User does not select any of the reasons.

3. User is informed that s/he must select one of the options in order to continue.


1. User reaches creating complaint interface of a profile page or item that the user has

already reported.

2. User is notified that a report is already submitted.


REQ. 17: System shall check whether the user has selected a reason to submit a report.

REQ. 18: System shall check whether the user has already submitted a report about the

content which is going to be reported.

3.2.14 READING COMPLAINTS


This feature will enable administrators to read complaints that are sent by standard

users. Using this feature, administrators will be able to sort, filter and read complaints before

taking any action. Therefore this feature will list complaint reports by showing priority,

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subject and item type which is reported. Alike reading messages feature, in the list, reports

that no action taken will be shown differently than the reports that actions taken against them.


3.2.14.2.1 Diagram


Primary

Actor

Facebook Administrator

Goal in

context

The purpose of this feature is to enable the administrators to read complaints

that are sent by standard users.

Trigger In order to control user activities, Facebook Administrators regularly read

complaint reports.

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1. Administrator reaches reading complaints interface from the administrator

homepage.

2. Administrator clicks any of the unread complaints.

3. Complaint content is fully shown to the administrator.

3. The complaint is marked as read.

4. Administrator leaves reading complaints interface.



2. Administrator clicks any of the listed complaints which are already marked

as read.

3. Complaint content is fully shown to the administrator.



4. Administrator wants to take an action to the complaint which is read.

5. Responding Complaints feature event flow is followed.


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3.2.15 RESPONDING COMPLAINTS


This feature will enable administrators to take actions to the complaints that are sent

by standard users. Using this feature, administrators will be able to delete user profiles,

remove shared posts, pictures, videos etc. and send notification messages. Therefore this

feature will let administrators select an appropriate action to the read complaint report. After

taking actions, the administrators will be informed about the completion of the process and

the priority of the report will be decreased and it will be shown as completed thereafter.


3.2.15.2.1 Diagram

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Primary

Actor

Facebook Administrator

Goal in

context

The purpose of this feature is to enable the administrators to take actions to the

complaints that are sent by standard users.

Preconditions No action must be taken against to the complaint report before.

Trigger In order to control user activities, Facebook Administrators must respond to the

complaint reports.


1. Administrator reaches responding complaints interface from the reading complaints

interface.

2. Administrator chooses any of the actions to take against the complaint.

3. Related actions are taken.

3. Administrator is informed about the completion of action.




2. Administrator does not select any of the actions.

3. Administrator is informed that at least one action must be taken.

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REQ. 18: System shall check whether the administrator chooses at least one action.

REQ. 19: System shall not let administrators to take actions to the complaints that are

completed.

4. NON-FUNCTIONAL REQUIREMENTS

4.1 PERFORMANCE REQUIREMENTS

System shall be available from all over the world at all times. Being a social network,

any interruption in the sharing chain will cause people to give up on Facebook, therefore it is

essential that the system shall be available at all times.

System shall not be affected from the number of active users in the system until half of

the registered users become active. Being a worldwide network, assuming that half of the

registered users are reaching to the website is a legitimate and necessary requirement.

4.2 DESIGN REQUIREMENTS

Design of the system shall arrange the content size as compatible for different

platforms, such as mobile phones, tablets and desktop computers. Since Facebook is based on

sharing with friends, design of the system shall let high level of mobile access.

Design of the system shall let different languages to be shown without affecting the

general layout and operations. Being a worldwide network, different language sets shall be

able to shown as the main language of the website without creating any obstacles on the

operations.

Documents

Software Requirement Specification for Facebook