RFC 2567
Design Goals for an Internet Printing Protocol
Design Goals for an Internet Printing Protocol 🎀
Okay bestie, this is RFC 2567, and it's giving Design Goals for an Internet Printing Protocol 🖨️✨. It's from the Network Working Group and was written by F.D. Wright at Lexmark International. It was published in April 1999 and it's in the Experimental category 🧪. The header doesn't list any RFC that it obsoletes or updates, so it's a fresh start 💖.
Status of this Memo 💅
This memo defines an Experimental Protocol for the Internet community, so it isn't an Internet standard of any kind. The authors want feedback and suggestions for improvement 🫶. Distribution of this memo is unlimited 🌸.
Copyright Notice 🔒
Copyright (C) The Internet Society (1999). All Rights Reserved.
IESG Note 📣
Okay, so the IESG is saying this is an Experimental protocol for the Internet community 🧪. They expect a revised version to get published as a Proposed Standard later on 👑. That version will probably be different from this one, especially because it's expected to add strong authentication and privacy features, plus an "ipp:" URL type that supports those security measures 🔐. Other changes are possible too 🙈.
Implementers, please be warned: future versions might not interoperate with the version of IPP defined here. And even if they do interoperate, some protocol features might not be available 💀.
The IESG also really wants people to experiment with this protocol, especially together with Transport Layer Security (TLS) [RFC2246] 🧚. The goal is to figure out how TLS can work well as a security layer for IPP 🔥.
Abstract ✨
Okay, this document is one piece of a whole set of documents that together describe everything about the new Internet Printing Protocol (IPP) 🖨️💜. IPP is an application-level protocol for distributed printing using Internet tools and technologies 🌈. This document takes a big-picture look at distributed printing, and it lists real-life scenarios that make clear which features a printing protocol for the Internet needs 🦋. It sets out requirements for three kinds of users: end users, operators, and administrators 👑. The design goals document picks out a subset of the end-user requirements that IPP/1.0 covers. Operator and administrator requirements are out of scope for version 1.0 🙅♀️.
The full IPP set includes these documents:
- Design Goals for an Internet Printing Protocol (this document)
- Rationale for the Structure and Model and Protocol for the Internet Printing Protocol [RFC2568]
- Internet Printing Protocol/1.0: Model and Semantics [RFC2568]
- Internet Printing Protocol/1.0: Encoding and Transport [RFC2565]
- Internet Printing Protocol/1.0: Implementer's Guide [ipp-iig]
- Mapping between LPD and IPP Protocols [RFC2569]
Here's the lowdown on each one 🍓:
The "Rationale for the Structure and Model and Protocol for the Internet Printing Protocol" document explains IPP from a high level, maps out the roadmap for the whole IPP spec suite, and gives the background and reasoning behind the IETF working group's big decisions 🗺️.
The "Internet Printing Protocol/1.0: Model and Semantics" document describes a simplified model. It has abstract objects, their attributes, and their operations, and it doesn't depend on encoding or transport 🧩. The model has a Printer and a Job object, and the Job can optionally support multiple documents 📄. IPP 1.0 semantics let end users and operators ask about printer capabilities, submit print jobs, check the status of jobs and printers, and cancel jobs ✅. This document also covers security, internationalization, and directory issues 🔐🌍.
The "Internet Printing Protocol/1.0: Encoding and Transport" document is the formal mapping of the abstract operations and attributes from the model document onto HTTP/1.1 🌐. It sets the encoding rules for a brand new Internet media type called "application/ipp" 💌.
The "Internet Printing Protocol/1.0: Implementer's Guide" document gives insight and advice to people building IPP clients and IPP objects 🛠️. It helps them understand IPP/1.0 and some of the things to consider when designing their client and/or IPP object implementations 🧠. For example, it gives a typical order for processing requests, including error checking ✔️. It also explains the reasons behind some of the specification decisions 💭.
The "Mapping between LPD and IPP Protocols" document offers some advice for implementers of gateways between IPP and LPD (Line Printer Daemon) implementations 🌉.
Table of Contents 📚
1. INTRODUCTION.....................................................4
2. TERMINOLOGY......................................................4
3. DESIGN GOALS.....................................................6
3.1. End-user.......................................................6
3.1.1. Finding or locating a printer................................6
3.1.2. Create an instance of the printer............................7
3.1.3. Viewing the status and capabilities of a printer.............7
3.1.4. Submitting a print job.......................................8
3.1.5. Viewing the status of a submitted print job..................9
3.1.6. Canceling a Print Job........................................9
3.2. Operator (NOT REQUIRED FOR V1.0)...............................9
3.2.1. Alerting.....................................................9
3.2.2. Changing Print and Job Status...............................10
3.3. Administrator (NOT REQUIRED FOR v1.0).........................10
4. OBJECTIVES OF THE PROTOCOL......................................10
4.1. SECURITY CONSIDERATIONS.......................................11
4.2. Interaction with LPD (RFC1179)................................12
4.3. Extensibility.................................................12
4.4. Firewalls.....................................................13
4.5. Internationalization..........................................13
5. IPP SCENARIOS...................................................13
5.1. Printer Discovery.............................................14
5.2. Driver Installation...........................................15
5.3. Submitting a Print Job........................................15
5.4. Getting Status/Capabilities...................................16
5.5. Asynchronous Notification.....................................17
5.6. Job Canceling.................................................17
6. Security Considerations.........................................18
7. REFERENCES......................................................18
8. ACKNOWLEDGMENTS.................................................19
9. AUTHOR'S ADDRESS................................................19
10. APPENDIX - DETAILED SCENARIOS..................................20
10.1. Printer discovery within an enterprise.......................20
10.2. Printer discovery across enterprises.........................21
10.3. Printer discovery on the Internet -logical operations........21
10.4. Printer discovery on the Internet - authentication...........22
10.5. Driver Download..............................................23
10.6. Submitting a print job as a file.............................24
10.7. Submitting a print job with two documents....................24
10.8. Submitting a print job as a file, printing fails.............25
10.9. Submitting a print job with authentication, PRIVACY and
payment......................................................26
10.10. Submitting a print job with decryption error................27
10.11. Submitting a print job with authentication..................28
10.12. Submitting a print job generated dynamically................29
10.13. Submitting a print job with a Printer jam - CANCELED........29
10.14. Submitting a print job with a Printer jam - recovered.......30
10.15. Submitting a print job with server pull.....................31
10.16. Submitting a print job with referenced resources............32
10.17. Getting Capabilities........................................33
10.17.1. Submission Attributes.....................................33
10.17.2. Printer Capabilities......................................33
10.18. Getting Status..............................................34
10.18.1. Printer State/Status......................................34
10.18.2. Job Status................................................34
10.18.3. Status of All My Jobs.....................................34
10.19. Asynchronous Notification...................................35
10.19.1. Job Completion............................................35
10.19.2. Job Complete with Data....................................35
10.19.3. Print Job Fails...........................................35
10.20. Cancel a job................................................36
10.21. End to end Scenario - within an enterprise..................36
10.22. End to end Scenario - across enterprises....................37
10.23. End to End Scenario - on the internet.......................40
11. Full Copyright Statement.......................................431. INTRODUCTION ✨
Okay so, the IPP protocol is seriously inspired by the printing model from the Document Printing Application (DPA) [ISO10175] standard 💅. DPA covers both end-user and administrative features, but IPP version 1.0 (IPP/1.0) only focuses on end-user functionality 🧡.
2. TERMINOLOGY ✨
Okay bestie, so Internet Printing here means using Internet tools, programs, servers and networks so end-users can print to a remote printer 🖨️💖 After the initial setup or configuration, it should feel exactly the same as printing to a printer that's attached to your computer or your local area network. It can include HTTP servers and browsers and other apps that handle static, dynamic and interactive printer locating services, user installation, selection, configuration, print job submission, printer capability inquiry and status inquiry of remote printers and jobs. Full-service, no cap 💅
For this document, a WEB Browser is software you can get from a bunch of sources, including but not limited to: Microsoft Internet Explorer, NCSA Mosaic, Netscape Navigator, Sun Hot Java! 🌐✨ Its main job is to use the Hypertext Transport Protocol (HTTP) to retrieve, interpret and display Hypertext Markup Language (HTML). Browsers are often part of a complete Internet Printing system because people use them to check the status of the printing system or find out more about it 👀 They may not be there in every implementation though, so don't count on them 🫶
Throughout this doc, 'printer' is anything that can mark on a piece of media, using whatever technology it has 🎀 The design goals don't cover multi-tiered printing setups with servers (one or many) sitting logically in front of the actual printing device. BUT those configurations are still supported, and they just have to look like a single device to the end-user. Main character energy for the printer, honestly 🦋
Also in this doc, 'driver' is the code installed on some client operating system that generates the print data stream for the intended printer. Some computing environments don't have a separate printer driver, and instead the right print data stream gets made inside an application on that computer 🧚 How that computer or application gets updated to support a new printer made available through IPP is outside the scope of IPP. The actual steps for installing a printer driver depend on the operating system, and those are also outside the scope of IPP. Check out Section 4.1 (SECURITY CONSIDERATIONS) for the security implications of driver download and installation 🔥
IPP is going to support these physical configurations:
- An IPP client talking to an IPP Printer object embedded in a single, physical output device.
- An IPP Client talking to a server that contains one or more IPP Printer objects. Each Printer object is associated with exactly one physical output device supported by the server. The protocol between the server and the output devices is undefined.
- An IPP Client talking to an IPP Printer object in a server. The Printer object is associated with one or more physical output devices, but the client only sees the Printer object, which is an abstraction and represents all of the associated physical output devices. The protocol between the server and the physical output devices is undefined.
Lowkey, some stuff in this doc is marked as NOT being part of version 1.0 (or V1.0) of the protocol, or as being handled by means outside of IPP 🌸 IPP is just one piece, an enabler, of a complete Internet Printing solution. For example, printer instance creation isn't performed by IPP, but IPP enables it. Operator and administrator wants and needs aren't in the design goals for version 1.0 at all 🙈 Some end-user wants and needs might also be excluded from version 1.0, and the description of each one will say so. Later versions of the protocol (e.g. V2.0) may add support for those initially excluded wants and needs ✨
3. DESIGN GOALS 💜
The next three sections cover the design goals for an Internet printing protocol from the three roles humans play: end-user, operator, and administrator 🧚 The goals here are only the ones an Internet printing protocol needs to address. Other wants and needs, like the operator needing physical access to the printer (for example, to load paper or clear jams), aren't covered by this document. Section 5 has scenarios with more detailed examples of the whole process, including discovery, status, printing and end-of-job reporting 🎬
3.1. END-USER
An end-user of a printer that accepts jobs through the Internet is one of the roles humans act in. The end-user is the person who submits a job to be printed on the printer 🫶
The end-user's wants and needs are broken down into six categories: finding/locating a printer, creating a local instance of a printer, viewing printer status, viewing printer capabilities, submitting a print job, viewing print job status, altering the attributes of a print job. (Yes, that's seven items in the list, and we're not going to talk about it 🙈)
3.1.1. Finding or locating a printer.
End-users want to be able to find and locate printers they're authorized to print to 🔍 They want to do this using a standard WEB browser or another application. Multiple criteria can be applied to find the printers they need. These criteria include but are not limited to:
- by name (Printer 1, Joes-color-printer, etc.)
- by geographic location (bldg 1, Kentucky, etc.)
- by capability or attribute (color, duplex, legal paper, etc.)
Also, while it's outside the scope of IPP, end-users want to be able to limit their searching to:
- inside a functional sub-domain
- include only a particular domain (lexmark.com)
- exclude specified domains
Even though an Internet printing protocol may not include this function by itself, IPP must define and enable a directory schema. That schema gives a directory service implementation what it needs to consistently represent printers by their IPP attributes 💅
3.1.2. Create an instance of the printer.
After finding the printer they want, an end-user needs to be able to create a local instance of that printer within their operating system or desktop 🖥️ What this local instance looks like depends on the printing paradigm of the operating system. For example, some UNIX users will only want a queue or a reference to a remote printer created on their machine, while other UNIX users and Windows NT users will want the queue plus the necessary icons and registry entries created and initialized 🍓 Where required, drivers may need to be downloaded from some repository and installed on the computer. All the necessary decompressing, unpacking, and other installation actions should happen without end-user interaction or intervention, except for the initial approval by the end-user. Once the local instance of the printer is installed, it shall appear to the end-user and to the applications running there as any other printer (local, local area network connected, or network operating system connected) on the end-user's desktop or environment ✨ IPP's role here is simply to enable creation of the printer instance by providing information, such as where to locate a printer driver for this printer, as an attribute of an IPP Printer.
3.1.3. Viewing the status and capabilities of a printer.
Before using a selected printer, or really at any time, the end-user needs to be able to verify the characteristics and status of both the printers and the jobs queued for them 👀 When checking a printer's characteristics, the end-user usually wants to know the device's capability, e.g.:
- supported media, commonly paper, by size and type
- paper handling capability, e.g. duplex, collating, finishing
- color capability
When checking the status of the printer and its print jobs, the end-user usually wants to be able to determine:
- is the printer on-line?
- what are the defaults to be used for printing?
- how many jobs are queued for the printer?
- how are job priorities assigned? (outside the scope of IPP)
3.1.4. Submitting a print job.
Once the desired printer has been located and installed, the end-user wants to print to it from normal applications using standard methods 🖨️💅 These normal applications include things like word processors, spreadsheets, database applications, WEB browsers, production printing applications, etc. The end-user may also want to print a file that already exists on their computer, which is called "simple push" 🫶 On top of printing from an app and simple push, the end-user needs to be able to submit a print job by reference. Printing by reference means submitting a job by providing a reference to an existing document. The reference, a URI, will be resolved before the actual print process occurs. Submitting a job by reference is a lifesaver because the user doesn't have to download the document from the remote server and then send it via IPP to the printer. That saves both time and network bandwidth 🦋
Some means shall be provided to determine whether the format of a job matches the capability of the printer. This can be done by one of the following (all of which are outside the scope of the IPP protocol):
- the end-user selects the correct printer driver
- the printer automatically selects the proper interpreter
- the end-user uses some other manual procedure
A standard action shall be defined for when the job's requirements don't match the capabilities of the printer 🚦
Because the end-user doesn't want to know the details of the underlying printing process, the protocol must support job-to-printer capability matching. (Not all implementations are necessarily required to implement this function.) This matching capability requires knowing both the printer's capabilities and attributes and the capabilities and attributes the job requires 🧠 Actions taken when a print job requires capabilities or attributes that aren't available on the printer vary, and can include but are not limited to:
- rejecting the print job
- redirecting the print job to another printer (Not in V1.0)
- printing the job, accepting differences in the appearance
Print jobs will also be submitted by background or batch applications without human intervention 🤖
End-users need to be able to set certain print job parameters at the time the job is submitted. These parameters include but are not limited to:
- number of copies
- single or two sided printing
- finishing
- job priority
3.1.5. Viewing the status of a submitted print job.
After a job has been submitted to a printer, the end-user needs a way to view its status (i.e. job waiting, job printing, job done) and to find out where the job is in the print queue 📍
On top of wanting to ask about a job's status, the end-user also needs automatic notification when that job completes 🔔
Notification means aren't defined by the protocol, but the protocol must provide a way to enable and disable the notification 💜
3.1.6. Canceling a Print Job
While a job is waiting to be printed, or has started but isn't completed yet, the original creator/submitter of the print job (i.e. the end-user) shall be able to cancel the job entirely (if it's waiting) or cancel the remaining portion of it (if it's printing.) Altering the print job itself is not a V1.0 design goal 🙅♀️💅
3.2. OPERATOR (NOT REQUIRED FOR V1.0) 🧚
okay so an operator is the human role for whoever runs a printer that takes jobs over the Internet 🖨️ their whole thing is keeping an eye on the printer's status and managing the jobs in its queue 💼 that includes restocking supplies (ink, toner, paper, etc.), clearing minor errors like paper jams, and reshuffling which end-user jobs go first 🔥 bestie, operator wants and needs won't be addressed by V1.0 of the protocol 🙈
operator wants include everything an end-user wants, plus maybe some extra powers ✨ like seeing all the jobs on a printer, while an end-user can only see their own 👀
3.2.1. Alerting. 🚨
One of the REQUIRED operator functions is being able to find out (or get alerted) when a printer's status changes, especially the changes that make it stop printing, and then actually fix the problem 🛠️ so an Internet printing protocol SHALL be able to alert a designated operator (or operators) about these conditions, like 'out of paper', 'out of ink', etc. plus, the operator SHALL be able to ask about a printer's or a job's status whenever they want, totally asynchronous to whatever the printer is doing else 📬
3.2.2. Changing Print and Job Status. 🔄
Another REQUIRED operator function is changing printer and job status remotely 💻 for example, the operator will need to be able to re-prioritize or cancel any print jobs on a printer they have authority over 👑
3.3. ADMINISTRATOR (NOT REQUIRED FOR V1.0) 🗝️
an administrator is the human role for whoever runs a printer that takes jobs over the Internet, and their job is creating the printer instances and deciding who's authorized as an end-user, operator, or administrator 🫶 admin wants and needs won't be addressed by V1.0 either 🙈
the admin's wants and needs include everything an end-user wants and, in some environments, some or all of what an operator wants 💅 minimally, the administrator MUST also have the tools, programs, utilities and supporting protocols available to be able to:
- create an instance of a printer
- create, edit and maintain the list of authorized end-users
- create, edit and maintain the list of authorized operators
- create, edit and maintain the list of authorized administrators
- create, customize, change or otherwise alter the manner in which the status capabilities and other information about printers and jobs are presented
- create, customize, or change other printer or job features
- administrate billing or other charge-back mechanisms
- create sets of defaults
- create sets of capabilities
the administrator MUST have the capability to do all of the above tasks either locally or remotely to the printer 🌸
4. OBJECTIVES OF THE PROTOCOL 🎯
the protocol an Internet printing working group defines will address end-user wants and needs (V1.0) 💖 it won't, at least at first, cover operator or administrator wants and needs (V2.0) 🌱
the protocol defined SHALL be independent of the operating system of both the client and the server ✨ generally, any platform capable of supporting a WEB Browser SHOULD be capable of being a client 💻 generally, any platform providing a WEB/HTTP server and printing services SHOULD be capable of being a server 🖥️ using the WEB Browser and Server is NOT REQUIRED for IPP; the operating system, operating system extensions or other applications MAY provide IPP functionality directly 🎀
in lots of environments like Windows 95, Windows NT and OS/2, the print data is created and sent to the printer on the fly, instead of being created, spooled, and then sent (the classic UNIX method 🐧) the Internet Printing Protocol MUST properly handle either methodology and make this transparent to the end-user 🦋
4.1. SECURITY CONSIDERATIONS 🔐
🚨 bestie, this part is serious. security is not the place for vibes only, so read it all.
it is REQUIRED that the Internet Printing Protocol be able to operate within a secure environment 🔒 wherever reasonable, IPP ought to make use of existing security protocols and services 🧠 IPP will not invent new security features when the design goals described in this document can be met by existing protocols and services 🙌 examples of such services include Secure Socket Layer Version 3 (SSL3) [SSL] and HTTP Digest Access Authentication [RFC2069]. Note: SSL3 is not on the IETF standards track.
since we can't predict the security levels or the specific threats that any given IPP print administrator might care about, IPP MUST be capable of operating with different security mechanisms and policies, as REQUIRED by the individual installation 🛡️ the initial security needs of IPP come from two main considerations. first, the printing environments described in this document account for the fact that the client, the Printer, and the document to be printed may each exist in different security domains 🌍 when objects are in different security domains, the design goals for authentication and message protection may be much stronger than when they are all in the same domain 💪
secondly, the sensitivity and value of the content being printed will vary from one print job to another 🎭 for example, a publicly available document doesn't need the same level of protection as a payroll document does 💰 message protection design goals include data origin authentication, privacy, integrity, and non-repudiation 🔏
in many environments (e.g. Windows, OS/2), a printer driver may be needed to create the proper datastream for the printer 🖨️ this document discusses downloading such a new driver from a variety of sources. downloading and installing any software, including drivers), on a computer exposes that computer to a number of security risks, including but not limited to:
- defective software
- malicious software (e.g. Trojan horses)
- inappropriate software (i.e. software doing something deemed unreasonable by the user.)
as such, proper security considerations and actions need to be taken by the user and/or a system administrator to prevent the compromising of the computer 🚫 administrators SHOULD configure the downloading mechanism for printer drivers so that it's able to verify the source of driver software and encrypt or otherwise protect that software during download 🔐
examples including security considerations can be found in sections 5 (IPP SCENARIOS) and 10 (APPENDIX - DETAILED SCENARIOS) later in this document 📖
4.2. INTERACTION WITH LPD (RFC1179) 🖨️
many versions of UNIX, and in fact other operating systems, provide a means of printing as described in [RFC1179] (Line Printer Daemon Protocol.) this document describes the file formats for the control and data files, as well as the messages used by the protocol 📄 because LPD takes a pretty simplistic approach, lots of manufacturers have added proprietary enhancements and extensions to 'lpd.' 🙃 because of this divergence, and due to other design goals described in this document, there is no requirement for backward compatibility or interoperability with 'lpd'. however, a mapping of LPD functionality and IPP functionality SHALL be provided so as to enable a gateway between LPD and IPP 🌉
4.3. EXTENSIBILITY 🧩
the Internet Printing Protocol SHALL be extensible in several ways that help with interoperability and prevent implementation collisions 🌈
- by providing a process where implementers can submit proposals for registration of new attributes and new enumerated values for existing attributes.
- that require review and approval. The Internet Assigned Number Authority (IANA) will be the repository for such accepted registration proposals after review.
- that do not require review and approval. IANA will be the repository for such registrations.
- by providing syntax in the protocol so that implementers may add private (i.e. unregistered) attributes and enumerated attribute values.
- by providing versioning and negotiation so that future implementations of IPP can interoperate with implementations of version 1.0 of IPP.
4.4. FIREWALLS 🧱
as stated in section 3 Design Goals, Internet printing SHALL, by definition, support printing from one enterprise to another 🏢 so the Internet printing protocol MUST be capable of passing through firewalls and/or proxy servers (where enabled by the firewall administrator), preferably without modification to the existing firewall technology 🦸
4.5. INTERNATIONALIZATION 🌍
users of Internet printing will come from all over the world 🗺️ so, where appropriate, internationalization and localization will be enabled for the protocol 💖
5. IPP SCENARIOS 🎬
each of the scenarios in this section describes a specific IPP operation, such as submitting a print job 📬 Section 10 contains several detailed flows for each scenario to give you more detail 🧁 the examples SHOULD NOT be considered exhaustive; they're illustrative of the functions and features REQUIRED in the protocol ✨ flows are meant to be protocol neutral. it is not assumed that all of the functions and features described in these scenarios will necessarily be supported directly by IPP or in version 1.0 of IPP 🙈
see the IPP Model and Semantics document for details on configurations of clients, servers and firewalls 💅
5.1. PRINTER DISCOVERY 🔍
Client Directory Service
Service
+----------------------------------------------------------- >
give me information on printers with these characteristics
< -----------------------------------------------------------+
Information on Printers matching these characteristicsokay so the whole point of printer discovery is finding printers that actually fit what the client wants and needs 💖 The Directory Service should give the client enough info to make an initial choice. The client may have to connect to each individual Printer offered to get more detail. Not all of the info from the Directory Service comes over IPP, btw. Some of it is administratively provided 🎀
The actual protocol between the client and the Directory or Name Service is outside the scope of IPP. Printer Discovery is in the scenarios to give design goals for the directory schema for IPP Printers and to further define Printer attributes 🧚
Characteristics that might be considered when locating a Printer include:
- capabilities of the Printer, e.g. PDLs supported
- physical location, e.g. in building 010
- driver required and location
- cost per page to print (outside the scope of IPP)
- whether or not printer is access controlled
- whether or not usage requires client authentication
- whether or not Printer can be authenticated
- whether or not payment is required for printing (outside the scope of IPP)
- maximum job size (spool size) (outside the scope of IPP)
- whether or not Printer support compression (outside the scope of IPP)
- whether or not Printer supports encryption
- administrative limits on this Printer
- maximum number of copies per job
- maximum number of pages per job
Responses could additionally include:
- how to get more information
- web page
- telephone number
- help desk
5.2. DRIVER INSTALLATION 💅
Client Printer
+----------------------------------------------------------- >
Where can I find a driver & software to install it?
< -----------------------------------------------------------+
URIs for drivers and install softwareokay, so a driver is the code installed in some client operating system that generates the print data stream for the intended printer 🖨️ The actual details for installing a printer driver depend on the operating system, and those are also outside the scope of IPP. Still, an IPP printer or a directory service advertising an IPP Printer should be capable of telling a client what drivers are available and/or required, where they can be found, and pointing to installation instructions, installation code or initialization strings required to install the driver.
Driver download and installation come with security implications, so check out section 4.1 (SECURITY CONSIDERATIONS) for the details. This part is not optional, bestie 🙈
5.3. SUBMITTING A PRINT JOB 📨
Client IPP Printer
+----------------------------------------------------------- >
Here is a Print Job
- Job attributes
- Print data
< -----------------------------------------------------------+
Responsethe protocol must support these sources of client data:
- Print data is a file submitted with the job
- Print data is generated on the fly by an application
- Print data is a file referenced by a URI
the protocol must handle overrun conditions in the printer, and it must support overlapped printing and downloading of the file for devices that can't spool files before printing them 😭
every print request gets a response ✨ Responses tell you whether the request succeeded or failed, and they give info about failures when they happen. Responses would include things like:
- Got the print job and queued it
- Got the print job and am printing it
- Got the print job, started to print it, but printing failed
- why it failed (e.g. unrecoverable PostScript error)
- state of the printer
- how much printed
- Got the print job but couldn't print it
- why it can't be printed
- state of the printer
- Got the print job but don't know what to do with it
- Didn't get a complete print job (e.g. communication failure)
5.4. GETTING STATUS/CAPABILITIES 📊
Client IPP Printer
+----------------------------------------------------------- >
Get status and/or capabilities of Printer
< -----------------------------------------------------------+
Status/Capabilitiesclients need to be able to get info about:
- Static capabilities of the device
- Dynamic state of the Printer (e.g. out of paper)
- State of a specific job owned by this client
- State of all jobs owned by this client
- queued
- printing
- completed
- Job submission attributes supported/required
- scheduling attributes (e.g. priority)
- production attributes (e.g. number of copies)
5.5. ASYNCHRONOUS NOTIFICATION 🔔
Client IPP Printer
+----------------------------------------------------------- >
Use the following method to notify me of Printer events
.
.
.
< -----------------------------------------------------------+
Asynchronous notification of Printer eventclients must be able to request asynchronous notification for Printer events like:
- job completion
- a fatal error that requires the job to be resubmitted
- a condition that severely impacts a queued job for this client e.g. printer is out of paper
Note: end-user notification is a V1.0 design goal, while operator notification is for V2.0. 🌈
5.6. JOB CANCELING 🚫
Client IPP Printer
+----------------------------------------------------------- >
Cancel the named job as indicated
< -----------------------------------------------------------+
Response (did it or not)similarly, clients must be able to make changes to jobs that have been submitted and are queued for printing. Changing job attributes should also be supported. Job modifications, and holding and releasing of jobs, are not included in the design goals for IPP v1.0 💜
6. SECURITY CONSIDERATIONS 🔐
the security considerations for IPP are described in Section 4.1 above. Go read it, it's serious business 🫶
7. REFERENCES 📚
- [ipp-iig] Hastings, T. and C. Manros, "Internet Printing Protocol/1.0: Implementer's Guide", Work in Progress.
- [RFC2569] Herriot, R., Hastings, T., Jacobs, N. and J. Martin, "Mapping between LPD and IPP Protocols", RFC 2569, April 1999.
- [RFC2566] deBry, R., Hastings, T., Herriot, R., Isaacson, S. and P. Powell, "Internet Printing Protocol/1.0: Model and Semantics", RFC 2568, April 1999.
- [RFC2565] Herriot, R., Butler, S., Moore, P. and R. Tuner, "Internet Printing Protocol/1.0: Encoding and Transport", RFC 2565, April 1999.
- [RFC2568] Zilles, S., "Rationale for the Structure and Model and Protocol for the Internet Printing Protocol", RFC 2568, April 1999.
- [ISO10175] ISO/IEC 10175, Document Printing Application, June 1996.
- [RFC1179] McLaughlin, L., "Line Printer Daemon Protocol" RFC 1179, August 1990.
- [SSL] Netscape, The SSL Protocol, Version 3, (Text version 3.02), November 1996.
8. ACKNOWLEDGMENTS 🌸
this document draws heavily from preliminary work done by others, especially in the Printer Working Group (PWG). The author gratefully acknowledges the specific contributions of:
Scott Isaacson Roger deBry
Novell Utah Valley State College
sisaacson@novell.com debryro@uvsc.edu
Carl-Uno Manros Robert Herriot
Xerox Sun
manros@cp10.es.xerox.com Robert.Herrior@pahv.xerox.xom
Tom Hastings Peter Zehler
Xerox Xerox
hastings@cp10.es.xerox.com Peter.Zehler@usa.xerox.com9. AUTHOR'S ADDRESS 🦋
F.D. (Don) Wright
Lexmark International
C14/035-3
740 New Circle Rd
Lexington, KY 40550
Phone: 606-232-4808
Fax: 606-232-6740
EMail: don@lexmark.com10. APPENDIX - DETAILED SCENARIOS 🎀
the following are more detailed scenarios showing how the Internet Printing Protocol is expected to be used as part of a complete Internet Printing system. Some parts of the scenarios include concepts, functions and information that may be outside the scope of version 1.0 of IPP (e.g. cost per page, payment means available, etc.). The info here is meant to be generic. There may not be an exact wording or terminology match between these scenarios and the implementation documents 🧐
10.1. PRINTER DISCOVERY WITHIN AN ENTERPRISE 🏢
a user wants to find a color Postscript printer in his/her enterprise that will print transparencies. The client, directory service, and printer are all behind the same corporate firewall. Because color foils are expensive, printers of this type are access controlled and require an account to be established, so printing can be billed back to the using department. Note the request to find a printer usable by Dept. J15. Drivers for all supported printers are available from the server they are associated with. A help desk is provided for end user support. The printer is unattended 🌈
Client Directory Service
+---------------------------------------------------------- >
Find a printer with these characteristics
- prints color, prints transparencies
- prints Postscript
- is in building 003
- accessible by the client
< ----------------------------------------------------------+
Printer "Color-A"
- prints color, prints transparencies
- prints Postscript
- in room H-6, building 003
- driver ABC-Postscript-V1.3 required, here is URI
- cost is $.45 per page for color transparencies
- limit is 10 pages per job
- authentication required to use printer
- printer is unattended
- help desk at x5001
Printer "Color-B"
- prints color, prints transparencies
- prints Postscript
- in room J-10, building 003
- driver XYZ-Postscript-V2.4 required, here is URI
- cost is $1.25 page for color transparencies
- limit is 5 pages per job
- authentication is required to use printer
- printer is unattended
- help desk at x500110.2. Printer Discovery Across Enterprises 🌍
okay so Company A's user needs to print a purchase order, but the printer she wants is at a business partner's place (Company B) 🤝 her client is behind one corporate firewall, while the directory service and the printer are behind a different corporate firewall 🧱 the good news is that drivers for every supported printer are available from the server they belong to, and there's a web page for end user support for public printers 💖
Client Company B Directory Service
+---------------------------------------------------------- >
Find a printer with these characteristics
- prints black and white
- is in El Segundo, building A
- is a public printer
< ----------------------------------------------------------+
Printer "Public-A"
- prints black and white
- prints Postscript
- in El Segundo, room H-6, building A
- driver ABC-Postscript-V1.3 required, here is URI
- printer is public
- help available at http://xerox/elSegundo/publicPrinters
Printer "Public-B"
- prints black and white
- prints PCL/5e
- is in El Segundo, room J-10, building A
- driver XYZ-PCL-V2.4 required, here is URI
- printer is public
- help available at http://xerox/elSegundo/publicPrinters10.3. Printer Discovery on the Internet - Logical Operations 🧮
a student wants to print her paper at the Ink-o's print shop in her neighborhood 📚 the report was made in Microsoft Word, and her budget is tight, so the cost matters a LOT 💸 notice how the query uses logical operators to get exactly the info she needs, which is so smart 🧠✨
Client Ink-o's Directory Service
+---------------------------------------------------------- >
Find a Printer with these characteristics
- prints color or black and white
- costs less than $.50 per page
- tell me about resolution and marking technology
< ----------------------------------------------------------+
Printer "Color-A"
- prints color
- 600 dpi laser printer
- prints Postscript
- driver ABC-Postscript-V1.3 required, here is URI
- cost is $.50 per page for color
- payment required prior to submitting print job
- here is URI for more information on Ink-o's
Printer "Mono-B"
- prints black and white
- 300 dpi inkjet printer
- prints Postscript
- driver XYZ-Postscript-V2.4 required, here is URI
- cost is $0.35 page for black and white
- payment required prior to submitting print job
- here is URI for more information on Ink-o's10.4. Printer Discovery on the Internet - Authentication 🔐
this executive is in her hotel room putting the finishing touches on a big presentation on her laptop 💼 she goes online to a local print shop to get her charts printed in time for tomorrow, so the shop has to be close to her hotel and able to print color transparencies 🎞️ she's also super picky about security, so she wants to know the printer can be authenticated and can take encrypted data. no compromises, bestie 💅
Client SirZippy Directory Service
+---------------------------------------------------------- >
Find a Printer with these characteristics
- prints color transparencies
- is in Boulder, Colorado
- Printer can be authenticated
- Printer supports encryption
Tell me when you are open for business
< ----------------------------------------------------------+
Printer "Color-A"
- prints color transparencies
- prints Postscript
- driver ABC-Postscript-V1.3 required, here is URI
- payment required prior to submitting print job
- Printer can be authenticated
- Data can be encrypted
- Located at 1670 Pearl Street, Boulder, CO
- This Branch is open 24 hours a day
Printer "Color-B"
- prints color transparencies
- prints Postscript
- driver ABC-Postscript-V1.3 required, here is URI
- payment required prior to submitting print job
- Printer can be authenticated
- Data can be encrypted
- Located at 1220 Arapahoe, Boulder, CO
- This Branch is open from 9:00 am to 6:30 pm10.5. Driver Download 💿
an end user at a company needs to print a super long report on a shiny new high speed PostScript printer 🖨️ she's gonna use it all the time, so she wants to download a driver and install it on her workstation. she's on Windows 95, which is a whole vibe 🕰️
Note: Driver download is not a V1.0 design goal. 🙈
Client IPP Printer
+---------------------------------------------------------- >
Tell me where to find print drivers for you
< ----------------------------------------------------------+
Driver install file is at
http://www.ibm.com/drivers/NP12a/Win9510.6. Submitting a Print Job as a File 📄
this end-user wants to send a print job, and the file is already sitting on his workstation 🗂️ the client and the printer are behind the same corporate firewall, and the printer is open to anyone behind it, so no authorization or authentication is needed 🙌 the data gets pushed over to the printer, which can spool the output, and nothing goes wrong. easy breezy 🦋
Client IPP Printer
+---------------------------------------------------------- >
Here is a print job
- job name = MyJob
- notify me by email when done printing
- print on iso-a4-white paper
- print on both sides of the paper
- return status of the printer in response
- document is in Postscript format
- here is the document to print
< ----------------------------------------------------------+
Print job accepted and spooled
- job id = #12345
- current state of print job = spooled
- submission time = 02/12/97, 15:35
- printer state = printing10.7. Submitting a Print Job with Two Documents 📑📑
same energy as before, the file is on the workstation, the client and printer share a corporate firewall, and no auth is needed 🫶 the difference here is that the job is made up of two separate documents 👯 the printer can spool, and no errors happen, so everything goes smoothly ✨
Client IPP Printer
+---------------------------------------------------------- >
Here is a print job
- job name = MyJob
- notify me by email when done printing
- print on iso-a4-white paper
- print on both sides of the paper
- return status of the printer in response
< ----------------------------------------------------------+
Print job accepted and spooled
- job id = #12345
- submission time = 02/12/97, 15:35
+---------------------------------------------------------- >
- here is the document to print
< ----------------------------------------------------------+
- OK
+---------------------------------------------------------- >
- here is the document to print, it is the last document.
< ----------------------------------------------------------+
- OK10.8. Submitting a Print Job as a File, Printing Fails 😭
okay this one is a little dramatic 💀 same setup again: file on the workstation, same firewall, no auth, data pushed to the printer. BUT this printer can't spool, so it starts printing while it's still receiving the file 🙃 then things go sideways. the user needs A4 paper, and the printer doesn't have any, so the printing fails and the job gets canceled 📉
Client IPP Printer
+---------------------------------------------------------- >
Here is a print job
- job name = MyJob
- notify me by email when done printing
- print on iso-a4-white paper
- print on both sides of the paper
- return status of the printer in response
- document is in Postscript format
- here is the document to print
< ----------------------------------------------------------+
Print job accepted
- printing failed
- current state of print job = canceled (A4 not available)
- submission time = 02/12/97, 15:35
- printer state = ready10.9. Submitting a Print Job with Authentication, Privacy and Payment 🔒💳
this traveling executive needs transparencies for a super important business meeting 🧳 her charts are in Lotus Freelance format on her notebook, and she found a SirZippy print shop near her hotel that prints color transparencies. the info is sensitive, so she wants her data sent to the Printer in an encrypted format 🛡️ she wants to authenticate the Printer, and the Printer authenticates her too, so it's mutual 🤝 and payment happens across the Internet. main character energy, fr 👑
Client IPP Printer
+---------------------------------------------------------- >
< ----------------------------------------------------------+
Mutual authentication and exchange of secret keys
+---------------------------------------------------------- >
Here is a print job (encrypted)
- job name = MyJob
- notify me by email when done printing
- print on iso-a4-white paper
- print on both sides of the paper
- return status of the printer in response
- tell me where to pick up output
- document is in Postscript format
- here is the document to print
< ----------------------------------------------------------+
Print job accepted and spooled (encrypted)
- job id = #12345
- current state of print job = spooled
- submission time = 02/12/97, 15:35
- printer state = printing
- payment required to proceed with job
- pick up at 230 East Main after 3:30 pm today
+---------------------------------------------------------- >
< ----------------------------------------------------------+
Payment transaction10.10. SUBMITTING A PRINT JOB WITH DECRYPTION ERROR 🔐
okay so picture this: a traveling executive needs to print transparencies for a big business meeting 💼✨ his charts are in Lotus Freelance format on his notebook, and he found a SirZippy print shop near his hotel that does color transparencies 🌈 the charts are sensitive, so he wants the data encrypted on the way to the printer 🔒 he also wants to authenticate the printer, and the printer authenticates him too 🫶 payment happens over the Internet 💸 and then, bestie, an error hits during decryption 😭
Client and IPP Printer do their thing like this:
Client IPP Printer
+---------------------------------------------------------- >
< ----------------------------------------------------------+
Mutual authentication and exchange of secret keys
+---------------------------------------------------------- >
Here is a print job (encrypted)
- job name = MyJob
- notify me by email when done printing
- print on iso-a4-white paper
- print on both sides of the paper
- return status of the printer in response
- tell me where to pick up output
- document is in Postscript format
- here is the document to print
< ----------------------------------------------------------+
Print job accepted and spooled (encrypted)
- job id = #12345
- current state of print job = spooled
- submission time = 02/12/97, 15:35
- printer state = printing
- payment required to proceed with job
- pick up at 230 East Main after 3:30 pm today
+---------------------------------------------------------- >
< ----------------------------------------------------------+
Payment transaction
.
.
.
< ----------------------------------------------------------+
Asynchronous response (email in this case)
- decryption failed on job #12345
- no pages printed
- current state of job = aborted10.11. SUBMITTING A PRINT JOB WITH AUTHENTICATION 🪪
this one's an end-user who wants to submit a print job 🖨️ the print file is already sitting on his workstation 💻 the client and printer are both behind the same corporate firewall 🧱 the printer is open to anyone behind that firewall, but authentication and authorization are required 🔑 authorization uses the authenticated end-user's name, the data gets pushed to the printer, and the printer can spool the output 🌸
Client IPP Printer
+---------------------------------------------------------- >
< ----------------------------------------------------------+
Authentication
Note: An authentication failure would end the transaction at
this point.
+---------------------------------------------------------- >
Here is a print job
- job name = MyJob
- notify me by email when done printing
- print on iso-a4-white paper
- print on both sides of the paper
- return status of the printer in response
- tell me where to pick up output
- document is in Postscript format
- here is the document to print
< ----------------------------------------------------------+
Print job accepted and spooled
- job id = #12345
- current state of print job = spooled
- submission time = 02/12/97, 15:35
- printer state = printing10.12. SUBMITTING A PRINT JOB GENERATED DYNAMICALLY ⚡
so here the print data is being generated on the fly ✨ a printer driver on the client workstation sends it along as it becomes available 💨 the client and printer are behind the same corporate firewall 🧱 the printer is open to anyone behind the firewall, and no authentication and authorization is required 🙌 the data gets pushed and the printer can spool the output 🖨️ and no error occurs, yay 🎀
Client IPP Printer
+---------------------------------------------------------- >
Here is a print job
- job name = MyJob
- notify me by email when done printing
- print on iso-a4-white paper
- print on both sides of the paper
- return status of the printer in response
- document is in Postscript format
- here is the print job
< ----------------------------------------------------------+
Print data accepted and spooling started
- job id = #12345
- current job state = spooled
- submission time = 02/12/97, 15:35
- printer state = printing10.13. SUBMITTING A PRINT JOB WITH A PRINTER JAM - CANCELED 🚫
okay this one is a little dramatic 😭 same setup: the print data is generated dynamically and a printer driver on the client workstation is sending it as it's available 💻 the client and printer sit behind the same corporate firewall 🧱 anyone behind the firewall can use the printer, and no authentication and authorization is required 🔓 the data is pushed to the printer, but this printer is not capable of spooling the output 😬 the printer jams, it notifies the user, and the user chooses to cancel the job 🙅♀️
Client IPP Printer
+---------------------------------------------------------- >
Here is a print job
- job name = MyJob
- notify me by email when done printing
- print on iso-a4-white paper
- print on both sides of the paper
- return status of the printer in response
- document is in Postscript format
- here is the document to print
< ----------------------------------------------------------+
Print data accepted and printing started
- job id = #12345
+---------------------------------------------------------- >
- What is the status of print job #12345?
< --------------------------------------------------------- +
- Job #12345 accepted but printer jammed, cannot continue
+---------------------------------------------------------- >
- Cancel job #12345
* Printer flushes remaining data
< ----------------------------------------------------------+
Print job terminated
- current job state = canceled
- submission time = 02/12/97, 15:35
- printer state = jammed10.14. SUBMITTING A PRINT JOB WITH A PRINTER JAM - RECOVERED 🛠️
plot twist, the jam gets fixed 🥹 same vibe as before: dynamically generated print data flowing from a printer driver on the client workstation 💨 same corporate firewall, same open-to-everyone-behind-it printer, no authentication and authorization required 🔓 the data is pushed, and this printer also can't spool the output 😮💨 it jams, notifies the user, and this time the user clears the jam and chooses to keep going 💪
Client IPP Printer
+---------------------------------------------------------- >
Here is a print job
- job name = MyJob
- notify me by email when done printing
- print on iso-a4-white paper
- print on both sides of the paper
- return status of the printer in response
- document is in Postscript format
- here is the document to print
< ----------------------------------------------------------+
Print data accepted and printing started
- job id = #12345
< --------------------------------------------------------- +
- Notification: printer jammed, cannot continue
* Jam is clear by human intervention, printing continues
+---------------------------------------------------------- >
Here is the last part of the document to print
< ----------------------------------------------------------+
Print job received
- current job state = printing
- submission time = 02/12/97, 15:35
- printer state = printing10.15. SUBMITTING A PRINT JOB WITH SERVER PULL 📥
here the print data lives in a file that's publicly available, and the printer does the pulling itself 🧲 the client and printer are behind the same corporate firewall 🧱 the printer is open to anyone behind the firewall, and no authentication and authorization is required 🔓 the printer can spool the output, and printing may begin before the whole job has been pulled 🖨️✨
Client IPP Printer
+---------------------------------------------------------- >
Here is a print job
- job name = MyJob
- notify me by email when done printing
- print on iso-a4-white paper
- print on both sides of the paper
- return status of the printer in response
- here is a reference to the data to be printed
< ----------------------------------------------------------+
Print data accepted and printing started
- job id = #12345
- current state of job = spooled
- submission time = 02/12/97, 13:15
- printer state = printing
.
.
< ----------------------------------------------------------+
Get the file to be printed
+---------------------------------------------------------- >
Here it is
Note: Failure to find the file, would end the transaction
with an error at this point and an asynchronous
notification would be send to the Client.
< ----------------------------------------------------------+
Data received10.16. SUBMITTING A PRINT JOB WITH REFERENCED RESOURCES 🔗
last one in this batch 🎀 part of the print data sits in a file on the user's workstation, and the client pushes it over 📤 but the print job also needs a resource that isn't inside that print file 🤔 the client and printer are behind the same corporate firewall 🧱 the printer is open to anyone behind the firewall, and no authentication and authorization is required 🔓 the printer can spool the output, and no errors occur 🙌
Client IPP Printer
+---------------------------------------------------------- >
Here is a print job
- job name = MyJob
- notify me by email when done printing
- print on iso-a4-white paper
- print on both sides of the paper
- return status of the printer in response
< ----------------------------------------------------------+
Print job accepted and spooled
- job id = #12345
- submission time = 02/12/97, 15:35
+---------------------------------------------------------- >
- here is the document to print
< ----------------------------------------------------------+
- OK
+---------------------------------------------------------- >
- here is the URI to print, it is the last document.
< ----------------------------------------------------------+
- OK
< ----------------------------------------------------------+
Get the external resource
+---------------------------------------------------------- >
Here it is10.17. GETTING CAPABILITIES ✨
10.17.1. Submission Attributes ✨
okay so this is the moment where an end-user wants to know which production and scheduling attributes the printer supports or requires before she submits anything 💅 the client then uses that info to build the print request 🎀
Client IPP Printer
+---------------------------------------------------------- >
I'm going to submit a Postscript job
give me your job submission attributes
< ----------------------------------------------------------+
Postscript production attributes for this Printer are:
- medium-select = us-letter-white, us-legal-white
- default is us-letter-white
- copies = 1,2,3,4,5
- default is 1
- print-quality = draft, normal, high
- default is draft
- sides = 1-sided, 2-sided-long-edge
- default is 2-sided-long-edge
- Job scheduling attributes for this Printer are:
- job-priority = 1,2,3
- default = 310.17.2. Printer Capabilities 🦋
this one is giving "tell me about yourself" energy 🙈 an end-user wants to find out the resolution, the marking technology, and which PDLs the printer supports
Client IPP Printer
+---------------------------------------------------------- >
Please tell me the
- resolution of the printer
- the marking technology of the printer
- PDLs supported
< ----------------------------------------------------------+
Printer resolution = 600 dpi
Marking Technology = laser
PDLs supported = Postscript level 2, PCL/610.18. GETTING STATUS 🌸
10.18.1. Printer State/Status
an end-user just wants to know how the printer is doing rn 🧚
Client IPP Printer
+---------------------------------------------------------- >
What is the state of the printer?
< ----------------------------------------------------------+
Printer state = out-of-paper10.18.2. Job Status 💜
an end user wants to check on a job she already sent in 📨
Client IPP Printer
+---------------------------------------------------------- >
Please tell me the status of job #12345
< ----------------------------------------------------------+
Job #12345 is queued
it is number 3 in the queue
printer state = printing10.18.3. Status of All My Jobs 🍓
same girl, but now she wants the full list of every job she has submitted to this Printer 📋
Client IPP Printer
+---------------------------------------------------------- >
Please tell me the status of my jobs
< ----------------------------------------------------------+
Job #00012 is complete
Printed at 12:35 on 01/23/97
Job #09876 is printing
Job #12345 is queued
it is number 3 in the queue
Job #34567 is queued
it is number 7 in the queue10.19. ASYNCHRONOUS NOTIFICATION 🔔
10.19.1. Job Completion 🎉
an end-user wants to hear about events that happen to her print jobs, and here the print job finishes with no errors at all, so the printer just tells her 💖
Client IPP Printer
< ----------------------------------------------------------+
Print job #123 completed10.19.2. Job Complete with Data 👑
same vibe, but this time she asked for every end-of-job detail, so the printer gives her the full rundown 🧾
Client IPP Printer
< ----------------------------------------------------------+
Print job #123 completed
- total pages printed = 15
- number of copies printed = 3
- total cost to print = $7.45
- pick up copies in room H-6, building 00510.19.3. Print Job Fails 💀
oof. the print job fails and the printer is unattended, so nobody is there to fix it. the notification still goes out though 😭
Client IPP Printer
< ----------------------------------------------------------+
Print job #123 failed
- total pages printed = 15
- number of pages submitted = 25
- printer-state = jammed10.20. CANCEL A JOB 🚫
the end-user sends a print job and then changes her mind and wants to cancel it 🙅♀️ notice that the printer asks for authentication before it will cancel anything 🔐
Client IPP Printer
+---------------------------------------------------------- >
< ----------------------------------------------------------+
Authentication.
+---------------------------------------------------------- >
Cancel job #1234
< ----------------------------------------------------------+
Job #1234 Canceled10.21. END TO END SCENARIO - WITHIN AN ENTERPRISE 🏢
okay picture an office worker printing on shared departmental printers 🖨️ every printer in the office is public, which means no authentication or authorization is needed. the printers are behind a firewall so outsiders can't reach them. there is no billing or accounting, most printing happens from desktop apps, and a help desk is there for printing problems. standard operating systems and applications are in use, and drivers get installed by hand by support staff. this scenario assumes the drivers are already installed and that they are not IPP aware, which means they can't talk over an IPP connection to get status or capabilities. the IPP printers show up in the application pull-down menus, and the printer configuration data is hard wired into the driver 🧠
first, the end-user picks print from the application pull-down menu and chooses an IPP printer from the list of Printers offered 🖱️
the driver pops up a dialogue with a hard-wired set of options for this printer. the end-user makes her choices and submits the job 💅
Client IPP Printer
+---------------------------------------------------------- >
Here is a print job
- job-name = memo-to-boss
- notify me by email when job is complete
- print on us-letter-white paper
- print 1 copy
- print at normal quality
- print on 1 side
- give me the state of the printer in responsethe driver generates the print data and hands it to the IPP driver a piece at a time, as it is generated 🧩
+---------------------------------------------------------- >
Here is the print data
< ----------------------------------------------------------+
Print data received, file is spooled
- printer state = printing
- time submitted = 2/12/97, 15:35
- current job state = spooledthe client adds this job to its list of current jobs, and that list (with the state of each job) is available from a pull-down menu on the client 📜
the end-user selects job #1234 from the list and clicks on it to see its status 👀
+---------------------------------------------------------- >
Give me the state of job #1234
and the state of the Printer
< ----------------------------------------------------------+
Job #1234 state = spooled
- it is number 3 in the queue
- printer state = printingand the job completes without error 🎊
< ----------------------------------------------------------+
Job #1234 completed
12 of 12 pages printed10.22. END TO END SCENARIO - ACROSS ENTERPRISES 🌍
now we're going cross-company 🤝 an office worker at Company A needs to print an office document on a "public" printer at Company B, which is a business partner. both companies have corporate firewalls, so the print request has to leave A's firewall and get into B's firewall. the office worker can browse public printers in Company B's directory service. the document comes from a desktop application. because the printer is "public", no authentication or authorization is needed. a driver gets downloaded, and this one IS IPP aware, meaning it can talk through the IPP protocol layer to get information about the printer dynamically 🦋
Client Company B's Directory Service
End user connects to B's Directory service
+---------------------------------------------------------- >
Find a Printer with these characteristics
- public (no authorization or authentication required)
- is in Lexington, building 004
- prints black and white
< ----------------------------------------------------------+
Printer "Public-A"
- http://www.lexmark.com/pubprinter/a
Printer "Public-B"
- http://www.lexmark.com/pubprinter/bthe end user picks Public-A 👆
Client Public-A
+---------------------------------------------------------- >
Where can I find a driver for you?
< ----------------------------------------------------------+
Drivers at http://www.lexmark.com/pubprinters/a/os245the end user grabs the driver and installs it on her PC 💻
she picks print from the application pull-down menu, and "Public-A" is selected from the list of Printers offered 🖨️
+---------------------------------------------------------- >
I'm going to submit a print job
give me your job submission attributes
< ----------------------------------------------------------+
Production attributes for this Printer are:
- medium-select = us-letter-white, us-legal-white
- default is us-letter-white
- copies = 1,2,3,4,5
- default is 1
- print-quality = draft, normal, high
- default is draft
- sides = 1-sided, 2-sided-long-edge
- default is 2-sided-long-edge
Job scheduling attributes for this Printer are:
- job-priority = 1,2,3
default = 3the driver puts up a dialogue with the available options and fills in the defaults ⚙️ the end-user makes her choices and submits the job 🚀
+---------------------------------------------------------- >
Here is a print job
- job-name = memo-to-Don-Wright
- notify me by email when job is complete
- print on us-letter-white paper
- print 1 copy
- print at normal quality
- print on 1 side
- give me the state of the printer in responsethe driver generates the print data and passes it to the IPP driver a piece at a time 🧩
+---------------------------------------------------------- >
Here is the print data
< ----------------------------------------------------------+
Print data received, and spooling started
print job id = #1234
Print data received, file is spooled
- printer state = printing
- time submitted = 2/12/97, 15:35
- current job state = spooledthe client adds this job to its list of current jobs, and that list (with the state of each job) lives in a pull-down menu on the client 📜
the end-user selects job #1234 from the list and clicks on it to see its status 👀
+---------------------------------------------------------- >
Give me the state of job #1234
and the state of the Printer
< ----------------------------------------------------------+
Job #1234 state = spooled
- it is number 3 in the queue
- printer state = printing
* The job completes without error
< ----------------------------------------------------------+
Job #1234 completed
12 of 12 pages printed10.23. END TO END SCENARIO - ON THE INTERNET ✨
okay so picture this: an executive is in her hotel room, finishing a super important presentation on her laptop 💼✨ she needs her charts printed for tomorrow, so she connects to a local print shop through the web. the print shop has to be convenient AND able to do color transparencies 🎀 she also has to download and temporarily install a driver so her laptop can make the PDL the print shop wants. the print shop requires mutual authentication, and payment has to happen in advance 💅 and the whole job is encrypted on the wire so nobody can eavesdrop 🔒 literally the most secure main character moment ever 👑
once the presentation is done, she heads to the web and visits the SirZippy home page 🌸
Client SirZippy Directory Service
+---------------------------------------------------------- >
Find me a printer with these characteristics
- Near Market Street in San Jose
- Prints color transparencies
- drivers can be downloaded
- supports privacy (encryption)
-the directory service looks up printers matching what she asked for 🔍
< ----------------------------------------------------------+
Printer "Color-A"
- located at 123 First Street in San Jose
- URI is http://www.SirZippy.com/FirstStreet/Color-A
- prints color transparencies
- 600 dpi laser
- driver ABC-Postscript-V1.3 available at this URI
- cost = $.75 per page
- authentication required to use printer
- payment required prior to printing
Printer "Color-B"
- located at 67 San Carlos Street, San Jose
- URI is http://www.SirZippy.com/SanCarlos/Color-B
- prints color transparencies
- 1200 dpi laser
- driver XYZ-PostScript-V4.3 available at this URI
- cost = $1.25 per page
- authentication required to use printer
- payment required prior to printing
- more information at this URIshe picks the first printer, "Color-A," because it's closer 📍 (honestly same, we all pick the closest one 🙈) so she connects to the URI to grab the driver 🧚
Client Driver URI
+---------------------------------------------------------- >
I need a driver for "Color-A"
< ----------------------------------------------------------+
Driver installer is at http://www.xerox.com/prtdrvrs
Driver is installed
User connects to
"Color-A"driver's installed, now she connects to the actual IPP printer ✨
Client IPP Printer "Color-A"
+---------------------------------------------------------- >
< ----------------------------------------------------------+
Mutual authentication and exchange of secret keys
+---------------------------------------------------------- >
I'm going to submit a print job
give me your job submission attributes
< ----------------------------------------------------------+
Production attributes for this Printer are:
- medium-select = us-letter-white, us-legal-white
- default is us-letter-white
- copies = 1,2,3,4,5
- default is 1
- print-quality = draft, normal, high
- default is draft
- sides = 1-sided, 2-sided-long-edge
- default is 2-sided-long-edge
Job scheduling attributes for this Printer are:
- job-priority = 1,2,3
default = 3they do the mutual auth and swap secret keys first, which is so iconic 🫶 then the printer tells the driver what it can do 💖
the driver pops up a dialogue with all the options and pre-fills the defaults 🌈 she makes her picks and submits the job 💅
+---------------------------------------------------------- >
Here is a print job
- job-name = presentation
- notify me by email when job is complete
- print on us-letter-transparency
- print 1 copy
- print at high quality
- print by 9:00 am tomorrow morning
- give me the state of the printer in responsethe driver makes the print data and sends it over one piece at a time, very organized 🍓
+---------------------------------------------------------- >
Here is the print data
< ---------------------------------------------------------+
Print data received, and spooling started
print job id = #1234
Print data received, file is spooled
- printer state = printing
- time submitted = 2/12/97, 15:35
- current job state = held, waiting for payment
+---------------------------------------------------------- >
< ----------------------------------------------------------+
Payment transaction
< ----------------------------------------------------------+
Job is scheduled to print, pick up after 9:00am tomorrow
Thank you for using SirZippyand that's the whole journey 🦋 her job is scheduled and held until payment clears, and she can grab the printouts after 9:00 am tomorrow. no notes, just vibes 💜
11. Full Copyright Statement ✨
so, the legal stuff, but make it cute 🎀 the copyright is The Internet Society's, 1999, and all rights are reserved 🔒
you're allowed to copy this document and hand it out to people. you can also make derivative works that comment on or explain it, or that help people implement it, and you can publish and distribute those too, in whole or in part, with no restrictions of any kind 💖 the one catch: every copy and derivative work has to keep the copyright notice and this paragraph ✨
the document itself, though, can't be modified in any way. that means no removing the copyright notice or the references to the Internet Society or other Internet organizations 🙅♀️ the exceptions are if you're developing Internet standards, in which case you have to follow the copyright procedures in the Internet Standards process, or if you're translating it into a language other than English 🌈
these permissions are perpetual, and the Internet Society or its successors or assigns won't revoke them 🫶
last thing, the disclaimer, which is serious so I'm keeping the caps 💀
This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
that's a wrap on the RFC, bestie 🧚💜
📦 where this page comes from
- ietf: rfc2567 1999-04
- 💖 girlified by claude-haiku-5-5 on : a language model's rewrite of the original, under its terms