Page 321 – VeryPDF DRM Protector

How many users can read the VPDF file? what’s the meaning for "Up to N documents"?

Dear Sir,

I am considering signing up for the $39.95 plan but had a couple of things I wanted to verify first. They are:

1. If the option “Is Online PDF (need internet)?” is selected I am assuming that if we have multiple people that access the .vpdf file online (on the VeryPDF server) each of them could be given a separate login. If we gave 500 people access to the .vpdf file, would we be up to 500 for “Up to N documents” in the purchase plan ?

https://drm.verypdf.com/purchase/

or would we just be on 1 .vpdf file with 500 separate logins.

2. If we chose to email a copy of the .vpdf file to 500 people, and lock the file to viewing on their hard disk or IP address, would that mean we were up to 500 for “Up to N documents” in the purchase plan.

or would we just be on 1 .vpdf file with 500 separate IP addresses.

If you could let me know this it will assist us to make a decision regarding the $ 39.95 plan.

Thank you.

Sincerely
Customer
————————————————–

>>I am considering signing up for the $ 39.95 plan but had a couple of things I wanted to verify first. They are:
>>1. If the option “Is Online PDF (need internet)?” is selected I am assuming that if we have multiple people that access the .vpdf file online (on the VeryPDF server) each of them could be given a separate login. If we gave 500 people access to the .vpdf file, would we be up to 500 for “Up to N documents” in the purchase plan ?
https://drm.verypdf.com/purchase/
>>or would we just be on 1 .vpdf file with 500 separate logins.

“Up to N documents” means that you can protect N documents, for each document, you can send it to any number of users as you want, for example, you can email the DRM PDF file to 500 or 1000 clients, every client will able to view this DRM PDF file without any problem, using same login and password.

Yes, you are right, it’s will be on 1 .vpdf file with 500 or 1000 or more separate logins.

>>2. If we chose to email a copy of the .vpdf file to 500 people, and lock the file to viewing on their hard disk or IP address, would that mean we were up to 500 for “Up to N documents” in the purchase plan.

No, “Up to N documents” is limited by number of documents, but not limited by the number of clients, after you protect 1 VPDF file, you can send it to 500 or more users to for reading.

>>or would we just be on 1 .vpdf file with 500 separate IP addresses.

“Lock by IP” will allow this VPDF file can only be read on this special IP address, if you will send the VPDF file to 500 or more peoples, you shouldn’t use this option, because your users may come from different IP addresses.

>>If you could let me know this it will assist us to make a decision regarding the $ 39.95 plan.

Thanks for your message, if you have any other questions, please feel free to let us know, we will assist you asap.

VeryPDF

VeryPDF DRM Creator Command Line Command Line options

E:\PDFDRM\VeryPDF-DRMCreator\drmpdf.exe
“VeryPDF PDF DRM Creator Command Line” version 3.0
Copyright 1996-2018 VeryPDF.com Inc.
Product Name: VeryPDF PDF DRM Creator Command Line

http://www.verypdf.com
http://www.verydoc.com
http://support.verypdf.com
Email:support@verypdf.com
Usage: drmpdf.exe [options] <PDF-file>
-json <string>                    : Use JSON file to encrypt PDF files, JSON file may contains all options
-IsNeedInternet <int>             : IsNeedInternetConnection
-enc-rc4v1                        : Use rc4v1 encryption
-enc-rc4v2                        : Use rc4v2 encryption (Default value)
-enc-aes                          : Use AES encryption (currently not supported)
-enc-upwd <string>                : An optional user password
-enc-opwd <string>                : The required owner password, *Required
-enc-print                        : Allow printing the document
-enc-edit                         : Allow modifying the document besides annotations, form fields or changing pages
-enc-copy                         : Allow text and graphic extraction
-enc-editnotes                    : Add or modify text annotations or form fields (if ePdfPermissions_Edit is set also allow to create interactive form fields including signature)
-enc-fillandsign                  : Fill in existing form or signature fields
-enc-accessible                   : Extract text and graphics to support user with disabilities
-enc-assemble                     : Assemble the document: insert, create, rotate delete pages or add bookmarks
-enc-highprint                    : Print a high resolution version of the document
-createvpdf <string>              : Create VPDF with unique key, Document ID of vPDF, same as -FileID
-FileID <string>                  : Create VPDF with unique key, Document ID of vPDF, same as -createvpdf
-FileKey <string>                 : The required open password
-FileName <string>                : Set original File name without path, like sample.xlsx
-SerialNo <string>                : SerialNo for vPDF
-email <string>                   : Set Email Account for vPDF
-DenySave <int>                   : DenySave
-DenySaveAs <int>                 : DenySaveAs
-RetainKeysInPDF <int>            : Retain Keys in vPDF file, so you can view the vPDF file in Adobe Reader and Adobe Acrobat
-opw <string>                     : owner password (for encrypted files)
-upw <string>                     : user password (for encrypted files)
-expiry-after-date <string>       : Expiry after a special date
-expiry-after-views <int>         : Expiry after a number of views
-expiry-after-prints <int>        : Expiry after a number of prints
-close-after-seconds <int>        : Close PDF Viewer after a limit time in seconds
-delete-after-expiry              : Delete PDF file after expiry
-limit-disk-id <string>           : DRM Protected PDF file can be viewed on special Disk only
-limit-ip <string>                : DRM Protected PDF file can be viewed on special IP only
-limit-usb-id <string>            : DRM Protected PDF file can be viewed on special USB only
-IsUseExpireAfterDate <int>       : IsUseExpireAfterDate
-SetIdleTime <int>                : Set Idle time for close document, Unit: seconds
-CloseAfterSeconds <int>          : Close PDF Viewer after a limit time in seconds, same as -close-after-seconds
-SetInvalidPWCount <int>          : If this value is greater than 0, and when user fail login on [SetInvalidPWCount] times, then don’t allow open vPDF any more
-LimitDiskID <string>             : same as -limit-disk-id
-LimitIP <string>                 : same as -limit-ip
-LimitUSBID <string>              : same as -limit-usb-id
-IsReceiveLogByEMail <int>        : Is receive log by email
-TitleOfMessage <string>          : Title message of this vPDF
-DescriptionOfMessage <string>    : String of content description of this vPDF
-LoginName <string>               : Login name for vPDF
-LoginPwd <string>                : Login password for vPDF
-LogonID1 <string>                : Login name for vPDF
-Password1 <string>               : Login password for vPDF
-LogonID2 <string>                : Login name for vPDF
-Password2 <string>               : Login password for vPDF
-LogonID3 <string>                : Login name for vPDF
-Password3 <string>               : Login password for vPDF
-LogonID4 <string>                : Login name for vPDF
-Password4 <string>               : Login password for vPDF
-LogonID5 <string>                : Login name for vPDF
-Password5 <string>               : Login password for vPDF
-stamp_type <int>                 : Stamp Type: 1 is Text, 2 is image, 3 is PDF, 4 is line
-stamp_text <string>              : Set Watermark text or full path/URL for image or PDF file
-stamp_x <int>                    : X offset value from current position, if you set X=-1, the current X position is equal to PageWidth/2
-stamp_y <int>                    : Y offset value from current position, if you set Y=-1, the current Y position is equal to PageHeight/2
-stamp_width <int>                : Set width for the stamp, or width to line stamp
-stamp_height <int>               : Set height for the stamp, if you set height=0, the current font size will be calculated automatically, fit to page width
-stamp_text_bold                  : Set Bold attribute to text stamp
-stamp_text_italic                : Set Italic attribute to text stamp
-stamp_text_fontname <string>     : Set font name for text stamp
-stamp_opacity <int>              : Watermark opacity option, the range is 0~100
-stamp_angle <int>                : Rotate the watermark, the range is -360~360
-stamp_color <string>             : Watermark color, e.g., 000000, FFFF00, 00FF00, etc.
-stamp_scale <int>                : Scale stamp’s size, the default is 100
-stamp_xpostype <int>             : xPosType: 0 is from left, 1 is from center, 2 is from right
-stamp_ypostype <int>             : yPosType: 0 is from top, 1 is from center, 2 is from bottom
-stamp_x2 <int>                   : Set End X position for Line stamp
-stamp_y2 <int>                   : Set End Y position for Line stamp
-stamp_pagerange <string>         : Set page range for the stamp, e.g., 1-5, 6-7, etc.
-stamp_importpdfpageindex <int>   : Import special page from PDF file as a stamp, start from page 1
-h                                : print usage information
-help                             : print usage information
–help                            : print usage information
-?                                : print usage information
-$ <string>                       : input your license key
Example:
drmpdf.exe D:\in.pdf
drmpdf.exe D:\in.pdf D:\out.vpdf
drmpdf.exe -opw 123 -upw 456 D:\in.pdf D:\in.vpdf
drmpdf.exe -expiry-after-date “2015/12/30 16:53” D:\in.pdf D:\out.vpdf
drmpdf.exe -expiry-after-views 10 D:\in.pdf D:\out.vpdf
drmpdf.exe -expiry-after-prints 10 D:\in.pdf D:\out.vpdf
drmpdf.exe -close-after-seconds 300 D:\in.pdf D:\out.vpdf
drmpdf.exe -delete-after-expiry D:\in.pdf D:\out.vpdf

You can run following command line to get DiskDrive ID Information,
wmic diskdrive get PNPDeviceID

drmpdf.exe -limit-disk-id “IDE\DISKHITACHI_HTS725050A7E630_________________GH2ZB390\4&15A50E0B&0&0.0.0” D:\in.pdf D:\out.vpdf

drmpdf.exe -limit-ip “216.58.221.78” D:\in.pdf D:\out.vpdf

drmpdf.exe -limit-usb-id “USBSTOR\DISK&VEN_GENERIC&PROD_EXTERNAL&REV_1.14\365644413254395620202020&0” D:\in.pdf D:\out.vpdf

drmpdf.exe -stamp_type 1 -stamp_text “VeryPDF Watermark” -stamp_x 1 -stamp_y 1 -stamp_xpostype 1 -stamp_ypostype 1 -stamp_text_bold -stamp_opacity50 -stamp_angle -30 -stamp_color FF0000 D:\in.pdf D:\out.vpdf

drmpdf.exe -stamp_type 1 -stamp_text “VeryPDF” -stamp_x 1 -stamp_y 1 -stamp_xpostype 1 -stamp_ypostype 1 -stamp_text_bold -stamp_opacity 50 -stamp_angle -45 -stamp_color FF0000 -close-after-seconds 50 -expiry-after-date “2015/12/30 16:53” -expiry-after-views 10 D:\in.pdf D:\out.vpdf

drmpdf.exe -stamp_type 2 -stamp_text “D:\logo.png” -stamp_x 100 -stamp_y 100 -stamp_width 200 -stamp_height 300 -stamp_opacity 50 D:\in.pdf D:\out.vpdf

drmpdf.exe -stamp_type 3 -stamp_text “D:\logo.pdf” -stamp_importpdfpageindex 1 -stamp_x 100 -stamp_y 100 -stamp_width 200 -stamp_height 300 -stamp_opacity 50 -close-after-seconds 50 -expiry-after-date “2015/12/30 16:53” -expiry-after-views 10 D:\in.pdf D:\out.vpdf

drmpdf.exe -stamp_type 4 -stamp_text line -stamp_x 100 -stamp_y 100 -stamp_x2 200 -stamp_y2 200 -stamp_width 20 -stamp_opacity 50 -stamp_color FF0000 D:\in.pdf D:\out.vpdf

drmpdf.exe -stamp_type 4 -stamp_text line -stamp_x 100 -stamp_y 100 -stamp_x2 200 -stamp_y2 200 -stamp_width 20 -stamp_opacity 50 -stamp_color FF0000 -close-after-seconds 50 -expiry-after-date “2015/12/30 16:53” -expiry-after-views 10 D:\in.pdf D:\out.vpdf

Following command line will protect all PDF files in D:\temp\ folder,
for %F in (D:\temp\*.pdf) do drmpdf.exe “%F” “%~dpnF.vpdf”

Following command line will protect all PDF files in D:\temp\ folder and sub-directories,
for /r D:\temp %F in (*.pdf) do drmpdf.exe “%F” “%~dpnF.vpdf”

Following command line will protect all PDF files in D:\temp\ folder and output files to C:\test folder,
for %F in (D:\temp\*.pdf) do drmpdf.exe “%F” “C:\test\%~nF.vpdf”

drmpdf.exe -stamp_type 1 -stamp_text “Confidential” -stamp_text_fontname “Arial Black” -stamp_x 1 -stamp_y 1 -stamp_xpostype 1 -stamp_ypostype 1 -stamp_text_bold -stamp_opacity 30 -stamp_angle -45 -stamp_color FF0000 -json test-offline.json

See Also:

Free Online PDF DRM Security

http://www.verypdf.com/online/free-online-pdf-drm-security.php

VeryPDF Cloud PDF DRM Protector

http://www.verypdf.com/app/cloud-pdf-drm-security/try-and-buy.html#buy

PDF Password Security

Encryption Algorithms and Key Lengths
PDF encryption makes use of the following encryption algorithms:

RC4, a symmetric stream cipher (i.e. the same algorithm can be used to encrypt and decrypt). RC4 no longer offers adequate security and has been deprecated in PDF 2.0.
AES (Advanced Encryption Standard) specified in the standard FIPS-197. AES is a modern block cipher which is used in a variety of applications.

Since the actual encryption keys are unwieldy binary sequences, they are derived from more user-friendly passwords which consist of plain characters. In the course of PDF and Acrobat development the PDF encryption methods have been enhanced to use stronger algorithms, longer encryption keys, and more sophisticated passwords.

Encryption algorithms, key length, and password length in PDF versions
PDF and Acrobat version	encryption algorithm and key length	max. password length and password encoding
PDF 1.1 – 1.3 (Acrobat 2-4)	RC4 40-bit (weak, should not be used)	32 characters (Latin-1)
PDF 1.4 (Acrobat 5)	RC4 128-bit(weak, should not be used)	32 characters (Latin-1)
PDF 1.5 (Acrobat 6)	same as PDF 1.4, but different application of encryption method (weak, should not be used)	32 characters (Latin-1)
PDF 1.6 (Acrobat 7) and PDF 1.7 = ISO 32000-1 (Acrobat 8)	AES-128	32 characters (Latin-1)
PDF 1.7 Adobe Extension Level 3 (Acrobat 9)	AES-256 with shortcomings in password handling (weak; deprecated in PDF 2.0)	127 UTF-8 bytes (Unicode)
PDF 1.7 Adobe Extension Level 8 (Acrobat X/XI/DC) and PDF 2.0 = ISO 32000-2	AES-256 with improved password handling	127 UTF-8 bytes (Unicode)

Note that AES-256 is not supported by the native PDF viewers on OS X/macOS (tested up to OS X 10.10.3) and iOS (tested up to iOS 8.1.3).

PDF encryption doesn’t apply the user or master password directly for encrypting the document contents, but calculates an encryption key from the password and other parameters including the permission settings. The length of the encryption key used for actually encrypting the document is independent from the length of the password (see table above).

Passwords

PDF encryption internally works with encryption keys of 40, 128, or 256 bit depending on the PDF version. The binary encryption key is derived from a password provided by the user. The password is subject to length and encoding constraints:

Up to PDF 1.7 (ISO 32000-1) passwords were restricted to a maximum length of 32 characters and could contain only characters from the Latin-1 encoding.
PDF 1.7 Adobe Extension Level 3 introduced Unicode characters and bumped the maximum length to 127 bytes in the UTF-8 representation of the password. Since UTF-8 encodes characters with a variable length of 1-4 bytes the allowed number of Unicode characters in the password is less than 127 if it contains non-ASCII characters. For example, since Japanese characters usually require 3 bytes in UTF-8 representation, up to 42 Japanese characters can be used in passwords.

In order to avoid ambiguities, Unicode passwords are normalized by a process called SASLprep (specified in RFC 4013 based on Stringprep in RFC 3454). This process eliminates non-text characters and normalizes certain character classes (e.g. non-ASCII space characters are mapped to the ASCII space character U+0020). The password is normalized to Unicode normalization form NFKC, and special bidirectional processing is applied to avoid ambiguities which may otherwise arise if right-to-left and left-to-right characters are mixed in a password.

The strength of PDF encryption is not only determined by the length of the encryption key, but also by the length and quality of the password. It is widely known that names, plain words, etc. should not be used as passwords since these can easily be guessed or systematically tried using a so-called dictionary attack. Surveys have shown that a significant number of passwords are chosen to be the spouse’s or pet’s name, the user’s birthday, the children’s nickname etc., and can therefore easily be guessed.

Security Recommendations

Keep in mind that only PDFs with a user password (required to open the document) are safe from cracking. The following should be avoided because the resulting encryption is weak and could be cracked:

Passwords consisting of 1-6 characters should be avoided since they are susceptible to attacks which try all possible passwords (brute-force attack against the password).
Passwords should not resemble a plain text word since the password would be susceptible to attacks which try all plaintext words (dictionary attack).
Passwords should contain non-alphabetic characters. Don’t use your spouse’s or pet’s name, birthday, or other items which are easy to determine.
40-bit RC4 according to PDF 1.3 (Acrobat 4) encryption should be avoided since it is susceptible to attacks which try all possible keys (brute-force attack against the encryption key).
The modern AES algorithm is preferable over the older RC4 algorithm.
AES-256 according to PDF 1.7 Adobe Extension Level 3 (Acrobat 9) should be avoided because it contains a weakness in the password checking algorithm which facilitates brute-force attacks against the password. For this reason Acrobat X/XI/DC no longer offer Acrobat 9 encryption for protecting new documents (only for decrypting existing documents).

In summary, AES-256 according to PDF 1.7 Adobe Extension Level 8/PDF 2.0 should be used. Passwords should be longer than 6 characters and should contain non-alphabetic characters.

VeryPDF VPDF Reader for Android

Description:

Covering all the essentials and more, VeryPDF VPDF Reader is one of the world’s leading mobile PDF solutions. Its expert features allow you to view both PDF and VPDF files. VPDF is VeryPDF’s DRM protected PDF files. With VeryPDF DRM, you can protect your PDF files, Office documents, photos, graphics and more. Protect your eBooks, reports, training materials with best encryption. Protect PDF, Office and Image files from unauthorized copying and distribution and audits their use.

VeryPDF DRM has more options to protect your documents, it allows you to block printing and copying, set printing, opening, IP address, expiry date limits and dynamic watermarks to your documents. You can also revoke access at any time. Online Center allows you to track user activities, include file opened date, IP address, and more.

VeryPDF VPDF Reader is a best App to view PDF and VPDF files for iPhone and iPad devices.

Key features:

Supports all mainstream file formats, including DOC, DOCX, PPT, PPTX, XLS, XLSX, RTF, TXT, PDF, VPDF, etc..
Quickly open PDF documents from email, the web, or any app that supports “Open In…”
View MS Word, Excel, PowerPoint, TXT and image files
Search, scroll, and zoom in and out.
Choose Single Page or Continuous scroll mode.
Reliable: 100% compliant with your current PDF ecosystem.
Lightweight: doesn’t exhaust your device resources.
Fast: no long waits to open PDFs.
Secure: powerful file protection features to safeguard sensitive information against unauthorized access.
Collaborative: full control of your content.
Multi-Language: support for 12 languages.
Rename, move, copy or delete PDF file(s)
Zip and unzip files

Contact Information:
Web: http://www.verypdf.com
Support: http://support.verypdf.com
Email: support@verypdf.com

WHAT’S NEW:
1. Support both PDF and VPDF formats.
2. Support 256bit AES protected PDF and VPDF files.

VeryPDF VPDF Reader for iOS (iPhone and iPad)

VeryPDF VPDF Reader is also named VeryPDF DRM PDF Reader, it can be used to view both PDF and VPDF files. You can download and install VeryPDF VPDF Reader from App Store for your iPhone and iPad devices.

https://itunes.apple.com/us/app/verypdf-vpdf-reader/id1332445787?ls=1&mt=8

Description:
Covering all the essentials and more, VeryPDF VPDF Reader is one of the world’s leading mobile PDF solutions. Its expert features allow you to view both PDF and VPDF files. VPDF is VeryPDF’s DRM protected PDF files. With VeryPDF DRM, you can protect your PDF files, Office documents, photos, graphics and more. Protect your eBooks, reports, training materials with best encryption. Protect PDF, Office and Image files from unauthorized copying and distribution and audits their use.

VeryPDF VPDF Reader is a best App to view PDF and VPDF files for iPhone and iPad devices.

Key features:

* Supports all mainstream file formats, including DOC, DOCX, PPT, PPTX, XLS, XLSX, RTF, TXT, PDF, VPDF, etc..
* Quickly open PDF documents from email, the web, or any app that supports “Open In…”
* View MS Word, Excel, PowerPoint, TXT and image files
* Search, scroll, and zoom in and out.
* Choose Single Page or Continuous scroll mode.
* Reliable: 100% compliant with your current PDF ecosystem.
* Lightweight: doesn’t exhaust your device resources.
* Fast: no long waits to open PDFs.
* Secure: powerful file protection features to safeguard sensitive information against unauthorized access.
* Collaborative: full control of your content.
* Multi-Language: support for 12 languages.
* Rename, move, copy or delete PDF file(s)
* Zip and unzip files

Contact Information:
Web: http://www.verypdf.com
Support: http://support.verypdf.com
Email: support@verypdf.com