WebSVN – oidinfo_new_design – Blame – /trunk/faq.raw.htm

Rev	Author	Line No.	Line
2	daniel-mar	1	<div id="global_content">
		2	<div id="table_faq">
		3	<table cellspacing="0" cellpadding="0" border="0" width="100%">
		4	<tr>
		5	<!--<td width="2%" valign="top"></td>-->
		6	<td valign="top" colspan="3">
		7	<span class="page_title">Frequently Asked Questions</span>
		8	<table>
		9	<tr>
		10	<td rowspan="2"><a href="/helper"><img src="images/helper.png" height="55" width="55" border="0" alt="OID helper" align="middle"></a></td>
		11	<td>Please check the Q&A below or ask your question directly to <a href="/helper">OID helper</a>.</td>
		12	</tr>
		13	<tr><td>To search for a particular OID, please use the <a href="basic-search.htm">search feature</a>.</td></tr>
		14	</table>
		15	<br><span class="page_subtitle">Questions</span>
		16	<ol>
		17	<li><a href="#1">What are the standards that define OIDs and the OID tree?</a></li>
		18	<li><a href="#2">Which kind of objects can be referenced by OIDs?</a></li>
		19	<li><a href="#3">Where can I learn more about OIDs and their registration?</a></li>
		20	<li><a href="#4">How to add information to the OID repository?</a></li>
		21	<li><a href="#modify">How to modify the description of an OID?</a></li>
		22	<li><a href="#6">How to delete an OID (or move it elsewhere in the OID tree)?</a></li>
		23	<li><a href="#7">How does the OID repository provided on this website compare with Harald Alvestrand's repository?</a></li>
		24	<li><a href="#8">How to reference an OID description from this repository?</a></li>
		25	<li><a href="#9">How many OIDs are currently described in this repository?</a></li>
		26	<li><a href="#10">How to get an OID assigned?</a></li>
		27	<li><a href="#national-RA">What decision needs be taken if a country wants a national Registration Authority for OIDs?</a></li>
		28	<li><a href="#12">Are there guidelines or standards regarding subsequent arcs of a country arc?</a></li>
		29	<li><a href="#13">What is the Internet OID?</a></li>
		30	<li><a href="#14">Where does the dot notation for OIDs come from?</a></li>
		31	<li><a href="#15">Why are top-level arcs restricted to three arcs numbered <tt>0</tt> to <tt>2</tt>, and why are arcs beneath top-level arcs <tt>0</tt> and <tt>1</tt> restricted to fourty arcs numbered <tt>0</tt> to <tt>39</tt>?</a></li>
		32	<li><a href="#16">What do we call a registration tree (or object identifier tree)?</a></li>
		33	<li><a href="#17">What is the ASN.1 notation of an OID?</a></li>
		34	<li><a href="#management">How is the entire registration tree managed?</a></li>
		35	<li><a href="#features">Which features are offered by this repository?</a></li>
		36	<li><a href="#syntax-rules">What are the syntax rules to enter information about OIDs through the web interface?</a></li>
		37	<li><a href="#oid-info">Which information is necessary to apply for an OID?</a></li>
		38	<li><a href="#example">Is there a particular OID that can be used for documenting examples of object identifiers?</a></li>
		39	<li><a href="#registration-authorities">What is the difference between the first and current Registration Authorities that appear in the description of some OIDs? What is their duty?</a></li>
		40	<li><a href="#mib">What constraints are imposed to OIDs used in SNMP MIBs (Management Information Bases)?</a></li>
		41	<li><a href="#lookup">Is there a way to look up an OID in the OID repository from my web browser?</a></li>
		42	<li><a href="#leaf">What is a leaf OID? What is a frozen OID?</a></li>
		43	<li><a href="#orphan">What is an orphan OID?</a></li>
		44	<li><a href="#iri">What is an OID-IRI (Internationalized Resource Identifier)?</a></li>
		45	<li><a href="#29">What are the duties of a Registration Authority?</a></li>
		46	<li><a href="#size-limitations">Are there size limitations for OID encoding?</a></li>
		47	<li><a href="#31">Are there binary encoders/decoders for OIDs?</a></li>
		48	<li><a href="#cookies">Does this web site use cookies?</a></li>
20	daniel-mar	49	<li><a href="#privacy">How does this web site protect users' privacy?</a></li>
15	daniel-mar	50	<li><a href="#guidelines">What are the guidelines to adequately describe an OID in this OID repository?</a></li>
2	daniel-mar	51	</ol><br></td>
		52	</tr>
		53	</table>
		54	</div>
		55	<div id="table_answers_in_faq">
		56	<table cellspacing="0" cellpadding="0" border="0" width="100%">
		57	<tr>
		58	<!--<td width="2%" valign="top"></td>-->
		59	<td valign="top" colspan="3">
		60	<span class="page_subtitle">Answers</span>
		61
		62	<ol>
		63	<li>
		64	<div class="question">
		65	What are the standards that define OIDs and the OID tree?<a name="1"></a>
		66	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		67	</div>
		68	<div class="answer">
28	daniel-mar	69	They are defined in the <a href="standards.htm">Recommendation ITU-T X.660 series \| ISO/IEC 9834 multi-part standard</a>, and in particular in <a href="https://itu.int/ITU-T/X.660">Rec.
		70	ITU-T X.660 \| ISO/IEC 9834-1</a>.<br>Binary encodings of OIDs are specified in <a href="https://itu.int/ITU-T/X.690">Rec.
2	daniel-mar	71	ITU-T X.690 \| ISO/IEC 8825-1</a> for the Binary (BER) and Distinguished
28	daniel-mar	72	(DER) Encoding rules, in <a href="https://itu.int/ITU-T/X.691">Rec.
2	daniel-mar	73	ITU-T X.691 \| ISO/IEC 8825-2</a> for the Packed Encoding rules (PER).
28	daniel-mar	74	An XML encoding of OIDs is specified in <a href="https://itu.int/ITU-T/X.693">Rec.
27	daniel-mar	75	ITU-T X.693 \| ISO/IEC 8825-3</a>. (See also <a href="#31">question
2	daniel-mar	76	31</a> about binary encoders/decoders for OIDs.)<br><br></div>
		77	</li>
		78	<li>
		79	<div class="question">
		80	Which kind of objects can be referenced by OIDs?<a name="2"></a>
		81	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		82	</div>
		83	<div class="answer">
		84	Objects that can typically be identified by an object identifier are
		85	(non exhaustively):
		86	<ul>
		87	<li>
		88	an <a href="/cgi-bin/display?tree=0.0">ITU-T Recommendation</a>,
		89	an <a href="/cgi-bin/display?tree=1.0&see=all">ISO International
		90	Standard</a>;
		91	</li>
		92	<li>
		93	a <a href="country_oids.htm">country</a>, a company, a
		94	project;
		95	</li>
		96	<li>
20	daniel-mar	97	a certificate policy specified according to <a href="https://itu.int/ITU-T/X.500">Rec.
2	daniel-mar	98	ITU-T X.500</a>;
		99	</li>
		100	<li>an encryption algorithm (for example <a href="/get/1.3.14.3.2.26">SHA-1</a>);</li>
		101	<li>
		102	<a href="/get/2.27">identification schemes</a> for tag-based
20	daniel-mar	103	applications (see <a href="https://itu.int/ITU-T/X.668">Recommendation
2	daniel-mar	104	ITU-T X.668 \| ISO/IEC 9834-9</a>);
		105	</li>
		106	<li>
		107	e-health data (for example, data from the <a href="/get/2.16.840.1.113883">HL7
		108	Consortium</a>);
		109	</li>
		110	<li>
		111	Common Alerting Protocol (<a href="/get/0.0.24.1303">CAP</a>)
		112	emergency messages;
		113	</li>
		114	<li>
		115	an attribute of an ITU-T X.500- or LDAP-based directory to make
		116	up a <code>DistinguishedName</code>;
		117	</li>
		118	<li>
		119	an ASN.1 module (for example, for the <a href="/get/2.41.0.1">BioAPI
		120	Interworking Protocol</a>), an ASN.1 type (or abstract syntax);
		121	</li>
		122	<li>
		123	a <a href="/cgi-bin/display?tree=2.1(1,2,3,4,5">set of ASN.1
		124	encoding rules</a>;
		125	</li>
		126	<li>a MIB for SNMP network management;</li>
		127	<li>
		128	a managed object class, one of its attributes, a notification
		129	or even other templates used in the area of network management
20	daniel-mar	130	and the GDMO standard (see <a href="https://www.itu.int/rec/T-REC-X.722/en">Recommendation
2	daniel-mar	131	ITU-T X.722 \| ISO/IEC 10165-4</a>);
		132	</li>
		133	<li>
20	daniel-mar	134	an information object (see <a href="https://www.itu.int/rec/T-REC-X.681/en">Recommendation
2	daniel-mar	135	ITU-T X.681 \| ISO/IEC 8824-2</a>);
		136	</li>
		137	<li>the type of some part of an ITU-T X.400 electronic message body;</li>
		138	<li>a file format;</li>
		139	<li>etc.</li>
		140	</ul>
20	daniel-mar	141	Examples of OID uses are also listed on the <a href="https://www.itu.int/oth/T0B04000048/en">ITU-T flyer</a>.<br><br></div>
2	daniel-mar	142	</li>
		143	<li>
		144	<div class="question">
		145	Where can I learn more about OIDs and their registration?<a name="3"></a>
		146	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		147	</div>
		148	<div class="answer">
		149	Apart from the <a href="standards.htm">official standards</a> (see
		150	<a href="faq.htm#1">question 1</a>), OIDs are explained in:
		151	<ul>
		152	<li>
20	daniel-mar	153	the <a href="https://www.itu.int/oth/T0B04000048/en">OID flyer</a>
2	daniel-mar	154	from ITU-T Study Group 17;
		155	</li>
		156	<li>
		157	the quick <a href="doc/introduction%20to%20object%20identifiers%20(OIDs).pdf">introduction
		158	to OIDs</a>;
		159	</li>
20	daniel-mar	160	<li>the ITU handbook "<a href="https://www.itu.int/pub/T-HDB-LNG.4-2010">Object identifiers (OIDs) and their registration authorities</a>";</li>
2	daniel-mar	161	<li>
26	daniel-mar	162	section 10.8 of Olivier Dubuisson's <a href="https://www.oss.com/asn1/resources/books-whitepapers-pubs/asn1-books.html#dubuisson">book
2	daniel-mar	163	"ASN.1 - Communication between heterogeneous systems"</a>;
		164	</li>
		165	<li>
26	daniel-mar	166	John Larmouth's <a href="https://www.oss.com/asn1/resources/books-whitepapers-pubs/asn1-books.html#larmouth">book
2	daniel-mar	167	"ASN.1 complete"</a>;
		168	</li>
		169	<li>
		170	John Larmouth's tutorial "Registration authorities
		171	for OID components" [<a href="doc/OID-tutorial.htm">html</a>]
		172	[<a href="doc/OID-tutorial.ppt">ppt</a>];
		173	</li>
		174	<li>
		175	the presentation "<a href="doc/MoU%20presentation%20on%20OIDs.pdf">Identifying
		176	objects: The ASN.1 approach</a>";
		177	</li>
		178	<li>see also <a href="#16">question 16</a>.<br><br></li>
		179	</ul>
		180	</div>
		181	</li>
		182	<li>
		183	<div class="question">
		184	How to add information to the OID repository?<a name="4"></a>
		185	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		186	</div>
		187	<div class="answer">
		188	This OID repository is not an official Registration Authority,
20	daniel-mar	189	so any OID <a href="#guidelines">described</a> in this OID repository has to be officially allocated
2	daniel-mar	190	by the Registration Authority of its parent OID. There are at least
		191	4 ways of adding a new OID description to the repository: <br>a. Enter the OID value in the box under "Add a description for the
		192	following OID to the database" on the <a href="index.htm">main page</a> and
		193	click on the "Create" button; a new page will then be displayed with
15	daniel-mar	194	some boxes to fill (see <a href="#guidelines">guidelines for describing an OID</a>). You can also enter the OID in the following box:<br><form method="post" action="/cgi-bin/manage" enctype="multipart/form-data">
2	daniel-mar	195	<input type="hidden" name="a" value="create">     <strong>{</strong>
		196	<input type="text" name="oid" size="30" value=""><strong>}</strong>
		197	<input type="submit" name="submit" value="Create"></form>
		198	b. Go to the parent OID of the OID that you want to add (i.e. the
		199	OID at the immediate upper level in the OID tree) and click on the
		200	"Create a child OID" link on the top right-hand side of the page;
15	daniel-mar	201	a new page will then be displayed with some boxes to fill (see <a href="#guidelines">guidelines for describing an OID</a>).<br>c. Go to an OID at the same level as the OID that you want to add
2	daniel-mar	202	(a.k.a. sibling OID) and click on the "Create a sibling OID" link
		203	on the top right-hand side of the page; a new page will then be displayed
20	daniel-mar	204	with some boxes to fill (see <a href="#guidelines">guidelines for describing an OID</a>).<br>d. If you have a lot of <a href="#guidelines">OID descriptions</a> to add, it is more convenient
2	daniel-mar	205	to describe them in an XML document that conforms to our <a href="oid.xsd">XML
		206	Schema for OIDs</a> and <a href="submit.htm">submit</a> this document
		207	through the web interface. <br><em>
		208	Note: In all 4 cases, the person (if any) you mention as <a href="#registration-authorities">registrant</a>
		209	for the OID, and the person (if known) who is the <a href="#registration-authorities">registrant</a>
		210	for the parent OID are automatically informed by email and can make
		211	comments on your submission. The description of an OID will not be
		212	visible until it is validated by the webmaster who is also automatically
		213	informed by email.
		214	</em><br><strong><br></strong>
		215	</div>
		216	</li>
		217	<li>
		218	<div class="question">
		219	<a name="modify"></a>How to modify the description of an OID?<a name="5"></a>
		220	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		221	</div>
		222	<div class="answer">
		223	If you want to update an OID that is described in the OID repository,
		224	please click on the "Modify this OID" hyperlink at the top-right
		225	of the web page that describes the OID or enter the OID in the following
		226	box:
		227	<form method="post" action="/cgi-bin/manage" enctype="multipart/form-data">
		228	<input type="hidden" name="a" value="modify">     <strong>{</strong>
		229	<input type="text" name="oid" size="30" value=""><strong>}</strong>
		230	<input type="submit" name="submit" value="Suggest a modification"></form>
		231	<em>
20	daniel-mar	232	Note: Your <a href="#guidelines">proposed modifications</a> will have to be validated by
2	daniel-mar	233	the <a href="#registration-authorities">registrant</a> of the OID
		234	being modified (if known), the <a href="#registration-authorities">registrant</a>
		235	of the parent OID (if known) and the OID repository administrator
		236	(who will all be automatically informed by e-mail) before they get
		237	published.
		238	</em><br>If the First or Current Registration Authorities requested privacy
		239	protection, their postal address, email address and phone number are
		240	not displayed (but you can receive them by email). In that case, please
		241	use the "Comments" box at the bottom of the "Suggest
		242	a modification" web page to describe the changes.<br>If an OID is misplaced in the OID tree and should be moved elsewhere
		243	in the tree, please use the "Comments" box at the bottom
		244	of the "Suggest a modification" web page to be displayed
		245	to explain where (and why) the OID should be moved.<br>You can also mention in the "Comments" box that an OID is
		246	a <a href="#leaf">leaf</a> in the OID tree (i.e. child OIDs cannot
		247	be allocated) or is <a href="#leaf">frozen</a> (i.e. no more child
		248	OIDs can be allocated).<br><br></div>
		249	</li>
		250	<li>
		251	<div class="question">
		252	How to delete an OID (or move it elsewhere in the OID tree)?<a name="6"></a>
		253	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		254	</div>
		255	<div class="answer">
20	daniel-mar	256	According to <a href="https://www.itu.int/rec/T-REC-X.660/en">Recommendation
2	daniel-mar	257	ITU-T X.660 \| ISO 9834-1</a>, an OID shall not be deleted once it
		258	has been allocated by a Registration Authority. However if an OID
		259	that is described in this OID repository has never been officially
		260	allocated by the Registration Authority for the parent OID (or is
		261	misplaced in the OID tree), you can request its deletion from the
		262	OID repository (or move elsewhere) by clicking on the "Modify
		263	this OID" hyperlink at the top-right of the web page that describes
		264	the OID or by entering the OID in the following box:
		265	<form method="post" action="/cgi-bin/manage" enctype="multipart/form-data">
		266	<input type="hidden" name="a" value="modify">     <strong>{</strong>
		267	<input type="text" name="oid" size="30" value=""><strong>}</strong>
		268	<input type="submit" name="submit" value="Suggest deletion"></form>
		269	Use the "Comments" box at the bottom of the page to be displayed
		270	to explain why the OID should be deleted (or moved elsewhere). Your
		271	suggestion will have to be validated by the registrant of the OID
		272	(if known), the registrant of the parent OID (if known) and the OID
		273	repository administrator (who will all be automatically informed by
		274	e-mail) before it get published.<br><br></div>
		275	</li>
		276	<li>
		277	<div class="question">
		278	How does the OID repository provided on this website compare with Harald Alvestrand's repository?<a name="7"></a>
		279	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		280	</div>
		281	<div class="answer">
		282	We get Harald's agreement to dump his repository and merge the data
		283	into our repository. This was done in June 2003 and our OID repository
20	daniel-mar	284	now encompasses <a href="https://www.alvestrand.no/objectid/">Harald's
2	daniel-mar	285	registry</a>.<br><br></div>
		286	</li>
		287	<li>
		288	<div class="question">
		289	How to reference an OID description in this repository?<a name="8"></a><a name="get"></a>
		290	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		291	</div>
		292	<div class="answer">
		293	The shortest and easiest means is to append the OID (whether it is
		294	in <a href="#17">ASN.1 notation</a>, <a href="#14">dot notation</a>,
3	daniel-mar	295	<a href="#iri">IRI notation</a> or <a href="https://datatracker.ietf.org/doc/html/rfc3061">URN
26	daniel-mar	296	notation</a>) to the <a href="/get/">http://oid-info.com/get/</a>
2	daniel-mar	297	URL, <em>e.g.</em>:
		298	<ul>
26	daniel-mar	299	<li> <a href="/get/2.999">http://oid-info.com/get/2.999</a> (recommended);</li>
2	daniel-mar	300	<li>
26	daniel-mar	301	<a href="/get/%7Bjoint-iso-itu-t%20example(999)%7D">http://oid-info.com/get/{joint
2	daniel-mar	302	iso-itu-t example(999)}</a> (ASN.1 notation);
		303	</li>
		304	<li>
26	daniel-mar	305	<a href="/get//Joint-ISO-ITU-T/Example">http://oid-info.com/get//Joint-ISO-ITU-T/Example</a>
		306	or <a href="/get//2/999">http://oid-info.com/get//2/999</a> (OID-IRI
2	daniel-mar	307	notation; with a '/' at the beginning of the OID notation, hence
		308	two '/'s after 'get');
		309	</li>
		310	<li>
26	daniel-mar	311	<a href="/get//Example">http://oid-info.com/get//Example</a>
2	daniel-mar	312	(OID-IRI notation using a long arc; with a '/' at the beginning
		313	of the OID notation, hence two '/'s after 'get');
		314	</li>
		315	<li>
26	daniel-mar	316	<a href="/get/urn:oid:2.999">http://oid-info.com/get/urn:oid:2.999</a>
2	daniel-mar	317	(URN notation).<br><br></li>
		318	</ul>
		319	</div>
		320	</li>
		321	<li>
		322	<div class="question">
		323	How many OIDs are currently described in this repository?<a name="9"></a>
		324	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		325	</div>
		326	<div class="answer">
15	daniel-mar	327	There are close to 2 billion OID descriptions stored in this repository
2	daniel-mar	328	(see <a href="/cgi-bin/display?a=count_nodes">exact number</a>). The
		329	repository is well alive and updated as often as necessary; <a href="/cgi-bin/display?a=count_nodes">statistics</a>
		330	are available about the number of OIDs added to the repository (or
		331	updated) over the past 12 months. A (non-exhaustive) list of standards
		332	(and other documents that define OIDs) which have been captured in
		333	our repository is <a href="captured-standards.htm">available</a>.<br><br></div>
		334	</li>
		335	<li>
		336	<div class="question">
		337	How to get an OID assigned?<a name="10"></a>
		338	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		339	</div>
		340	<div class="answer">
20	daniel-mar	341	The original intention of the <a href="https://www.itu.int/rec/T-REC-X.660/en">Recommendation
2	daniel-mar	342	ITU-T X.660 \| ISO/IEC 9834</a> series was that anyone should be able
		343	to get an OID if they needed one. There are registration authorities
		344	from which it is easy and quite cheap (sometimes even free!) to have
		345	an OID assigned, such as:
		346	<ul>
		347	<li>
		348	If you only need an OID for an example in a document, use <code><a href="/get/2.999">{joint-iso-itu-t(2)
		349	example(999)}</a></code> as explained in <a href="#example">question
		350	22</a>.
		351	</li>
		352	<li>
		353	<a href="country_oids.htm#agreements">Several countries</a>
		354	assign OIDs (usually after paying a fee decided by the national
		355	registration authority) under their country arc <a href="/get/2.16"><code>{joint-iso-itu-t(2)
		356	country(16)}</code></a> and/or <a href="/get/1.2"><code>{iso(1)
		357	member-body(2)}</code></a> (see <a href="country_codes.htm">correspondence
		358	table between country codes and OIDs</a>). (Note: If you are representing
		359	a country and want to nominate a registration authority for your
		360	country arc under <a href="/get/1.2"><code>{iso(1) member-body(2)}</code></a>
		361	or <a href="/get/2.16"><code>{joint-iso-itu-t(2) country(16)}</code></a>,
		362	please see <a href="#11">question 11</a> below.)
		363	</li>
		364	<li>
20	daniel-mar	365	<a href="https://pen.iana.org/pen/PenApplication.page">IANA</a>
2	daniel-mar	366	(Internet Assigned Numbers Authority) hands out OIDs for free under
		367	<a href="/get/1.3.6.1.4.1"><code>{iso(1) identified-organization(3)
		368	dod(6) internet(1) private(4) enterprise(1)}</code></a>; these OIDs
		369	are used a lot (but not only) to identify Management Information
		370	Bases (MIBs) for network management (SNMP).
		371	</li>
		372	<li>
20	daniel-mar	373	<a href="https://oidplus.viathinksoft.com/oidplus/?goto=oidplus:com.viathinksoft.freeoid">ViaThinkSoft</a>
2	daniel-mar	374	freely assigns an OID to private persons and developers of freeware,
		375	shareware or open-source software under <a href="/get/1.3.6.1.4.1.37476.9000"><code>{iso(1)
		376	identified-organization(3) dod(6) internet(1) private(4) enterprise(1)
		377	37476 freesub(9000)}</code></a>.
		378	</li>
		379	<li>
20	daniel-mar	380	<a href="https://webapp.etsi.org/ASN1ObjectTree/ASN1.asp">ETSI</a>
2	daniel-mar	381	(European Telecommunication Standards Institute) hands out OIDs
		382	under <code><a href="/get/0.4.0.127.0">{itu-t(0) identified-organization(4)
		383	etsi(0) reserved(127) etsi-identified-organization(0)}</a></code>
		384	even for non-ETSI-members.
		385	</li>
		386	<li>
		387	Network operators can have an OID assigned by ITU-T under <code><a href="/get/0.3">{itu-t(0)
		388	network-operator(3)}</a></code>; telecom operators can have an OID
		389	assigned by their national PTT administration under <code><a href="/get/0.2">{itu-t(0)
		390	administration(2)}</a></code>.
		391	</li>
		392	<li>
20	daniel-mar	393	For the health sector, see <a href="https://wiki.hl7.org/index.php?title=HL7_OID_Registry_Frequently_Asked_Questions#Somebody_told_me_I_need_an_OID_for_my_Organization._What_do_I_do.3F">HL7's
2	daniel-mar	394	FAQ</a>.
		395	</li>
		396	<li>
20	daniel-mar	397	Dave Harvey (UK) <a href="https://www.medicalconnections.co.uk/Free_UID">sub-delegate
		398	ranges of his own OID</a> to anyone who uses a <a href="https://www.dicomstandard.org">DICOM</a>
2	daniel-mar	399	toolkit (communication in medicine).
		400	</li>
		401	<li>
20	daniel-mar	402	You can <a href="https://learn.microsoft.com/en-us/windows/win32/ad/obtaining-an-object-identifier-from-microsoft?redirectedfrom=MSDN">obtain
2	daniel-mar	403	an OID from Microsoft</a> to extend the Active Directory schema.
		404	</li>
		405	<li>
20	daniel-mar	406	You can <a href="https://www.itu.int/ITU-T/asn1/uuid.html#UUID%20Generation%20&%20Registration">generate
2	daniel-mar	407	a UUID</a> (or use a UUID that you already hold) and append it as
		408	a subsequent arc of <a href="/get/2.25"><code>{joint-iso-itu-t(2)
		409	uuid(25)}</code></a> (without registering it, in particular in this
		410	OID repository, because it is guaranteed to be globally unique with
20	daniel-mar	411	a high probability) according to <a href="https://www.itu.int/rec/T-REC-X.667/en">Recommendation
2	daniel-mar	412	ITU-T X.667 \| ISO/IEC 9834-8</a> (but see <a href="#size-limitations">question
		413	30 about size limitations of OID encodings</a>).
		414	</li>
		415	</ul>
		416	<em>Important note</em>: OIDs have to be requested from those registrations authorities because this OID repository
		417	is
		418	<em>not</em> a registration authority.
		419	<br><br></div>
		420	</li>
		421	<li>
		422	<div class="question">
		423	What decision needs be taken if a country wants a national Registration Authority for OIDs?<a name="11"></a><a name="national-RA"></a><a name="country"></a>
		424	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		425	</div>
		426	<div class="answer">
		427	Country arcs are the subsequent arcs of <a href="/get/1.2"><code>{iso(1)
		428	member-body(2)}</code></a> and <a href="/get/2.16"><code>{joint-iso-itu-t(2)
		429	country(16)}</code></a>. The values assigned to country arcs are the
20	daniel-mar	430	<a href="https://unstats.un.org/unsd/methods/m49/m49alpha.htm">numerical
2	daniel-mar	431	codes</a> (without leading zeros) assigned by the United Nations Statistics
		432	Division together with the corresponding and the <a href="https://www.iso.org/obp/ui/#search">ISO
		433	3166-1-alpha-2 code</a>. <a href="/get/1.2"><code>{iso(1) member-body(2)}</code></a>
		434	was deprecated in favour of <a href="/get/2.16"><code>{joint-iso-itu-t(2)
		435	country(16)}</code></a>, thus countries which have never been operating
		436	a national Registration Authority (RA) for OIDs are encouraged to
		437	request an arc under <a href="/get/2.16"><code>{joint-iso-itu-t(2)
		438	country(16)}</code></a>. Countries are discouraged to request an arc
		439	under both <a href="/get/1.2"><code>{iso(1) member-body(2)}</code></a>
20	daniel-mar	440	and <a href="/get/2.16"><code>{joint-iso-itu-t(2) country(16)}</code></a>.<br><a href="https://www.itu.int/rec/T-REC-X.660/en">Recommendation ITU-T
		441	X.660 \| ISO/IEC 9834-1</a>, clause A.4.5, specifies that the <a href="https://www.iso.org/members.html">ISO
		442	National Body</a> of the country and the <a href="https://www.itu.int/hub/membership/our-members/">administration
2	daniel-mar	443	representing the country in the ITU</a> shall agree together (as a
		444	national decision) on the organization that will be the RA for their
		445	country arc. In the case of a country arc under <a href="/get/1.2"><code>{iso(1)
20	daniel-mar	446	member-body(2)}</code></a> the decision is only taken by the <a href="https://www.iso.org/members.html">ISO
2	daniel-mar	447	National Body</a> of the country. For more detailed information, see
		448	"<a href="country_oids.htm">Operation of a country Registration
		449	Authority</a>".<br>One way to know if your country is already operating an RA for OIDs
		450	is too check the <a href="country_oids.htm#agreements">known
		451	country RAs</a>.<br><br></div>
		452	</li>
		453	<li>
		454	<div class="question">
		455	Are there guidelines or standards regarding subsequent arcs of a country arc?<a name="12"></a>
		456	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		457	</div>
		458	<div class="answer">
		459	Country arcs are the subsequent arcs of <a href="/get/1.2"><code>{iso(1)
		460	member-body(2)}</code></a> and <a href="/get/2.16"><code>{joint-iso-itu-t(2)
		461	country(16)}</code></a>.<br>The structure underneath a country arc is a national decision. The
20	daniel-mar	462	basic standard is of course <a href="https://www.itu.int/rec/T-REC-X.660/en">Recommendation
2	daniel-mar	463	ITU-T X.660 \| ISO/IEC 9834-1</a>. It might be worth having a look
20	daniel-mar	464	at <a href="https://www.itu.int/rec/T-REC-X.670/en">Recommendation
2	daniel-mar	465	ITU-T X.670</a> "<em>
		466	Procedures for registration agents operating
		467	on behalf of organizations to register organization names subordinate
		468	to country names
		469	</em>".<br>There is no guidelines besides the fact that any registration authority
		470	needs to keep records according to the aforementioned standards. A
		471	good idea is probably to look at <a href="country_oids.htm#agreements">how
		472	other countries have organized subsequent arcs beneath their country
20	daniel-mar	473	arc</a> as well as reading the ITU handbook on "<a href="https://www.itu.int/pub/T-HDB-LNG.4-2010"><em>
2	daniel-mar	474	Object
		475	identifiers (OIDs) and their registration authorities
15	daniel-mar	476	</em></a>". You can also take benefit from the
		477	<a href="#guidelines">guidelines to adequately describe an OID in this OID repository</a>.<br><br></div>
2	daniel-mar	478	</li>
		479	<li>
		480	<div class="question">
		481	What is the Internet OID?<a name="13"></a>
		482	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		483	</div>
		484	<div class="answer">
		485	The Internet OID is <code><a href="/get/1.3.6.1">{iso(1) identified-organization(3)
		486	dod(6) internet(1)}</a></code> or equivalently in dot notation <code><a href="/get/1.3.6.1">1.3.6.1</a></code>.<br><br></div>
		487	</li>
		488	<li>
		489	<div class="question">
		490	Where does the dot notation for OIDs come from?<a name="14"></a>
		491	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		492	</div>
		493	<div class="answer">
20	daniel-mar	494	(<em>from Harald Alvestrand's <a href="https://www.alvestrand.no/objectid/index.html">website</a></em>)<br>The dot notation is an IETF invention. The ASN.1 group thought it
2	daniel-mar	495	better to have a notation using spaces and braces, with optional text
		496	labels, so that <code>1.3.6.1</code> would become something like <code>{iso(1)
		497	identified-organization(3) dod(6) internet(1)}</code> or <code>{1
		498	3 6 1}</code> or variants thereof.<br>The IETF folks thought this was somewhat inconvenient, and decided
		499	to use a space-free notation. This is, among other things, spelled
3	daniel-mar	500	out in IETF <a href="https://datatracker.ietf.org/doc/html/rfc1778">RFC 1778,
		501	section 2.15</a>, but was in use long before that time. IETF <a href="https://datatracker.ietf.org/doc/html/rfc2252">RFC
2	daniel-mar	502	2252, section 4.1</a>, eliminates the "<code>ds.4.10</code>" form.<br><br></div>
		503	</li>
		504	<li>
		505	<div class="question">
		506	Why are top-level arcs restricted to three
		507	arcs numbered <code>0</code> to <code>2</code>, and why are arcs beneath
		508	top-level arcs <code>0</code> and <code>1</code> restricted to fourty
		509	arcs numbered <code>0</code> to <code>39</code>?<a name="15"></a>
		510	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		511	</div>
		512	<div class="answer">
		513	This enables optimized binary encodings in which all arcs beneath
		514	top-level arcs <code>0</code> and <code>1</code>, and arcs <code>0</code>
		515	to <code>47</code> beneath top-level arc <code>2</code> are encoded
20	daniel-mar	516	on a single octet (see <a href="https://www.itu.int/rec/T-REC-X.690/en">Rec.
2	daniel-mar	517	ITU-T X.690 \| ISO/IEC 8825-1</a>, clause 8.19). Arcs greater to <code>47</code>
		518	benath top-level arc <code>2</code> are hence encoded on more than
		519	one octet.<br><br></div>
		520	</li>
		521	<li>
		522	<div class="question">
		523	What do we call a registration tree (or object identifier tree)?<a name="16"></a>
		524	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		525	</div>
		526	<div class="answer">
		527	In an open and international world such as the one of telecommunications
		528	and information technologies, you often need to be able to reference
		529	an "object" (see <a href="#1">question 1</a>) in a unique and universal
		530	way. The ASN.1 standard defines an object as being "<em>
		531	a well-defined
		532	piece of information, definition or specification which requires a
		533	name in order to identify its use in an instance of communication
		534	</em>".<br>In general, an object is a class of information (for example, a file
		535	format), rather than an instance of such a class (for example, an
		536	individual file). It is thus the class of information (defined by
		537	some referenceable specification), rather than the piece of information
		538	itself, that is assigned a place in the tree.<br>The naming structure that has been chosen is a tree structure that
		539	allows to name objects in a local or international context, without
		540	beeing limited either by the registration authority, nor by the number
		541	of objects they can register.<br><br></div>
		542	</li>
		543	<li>
		544	<div class="question">
		545	What is the ASN.1 notation of an OID?<a name="17"></a>
		546	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		547	</div>
		548	<div class="answer">
		549	Each OID arc is associated with a mandatory number (used for data
		550	transfers) and an optional (but recommended) alphanumeric identifier
		551	(for legibility).<br>An identifier begins with a lower-case letter (from '<code>a</code>'
		552	to '<code>z</code>') and is followed by lower-case or upper-case letters
		553	(from '<code>a</code>' to '<code>z</code>', or from '<code>A</code>'
		554	to '<code>Z</code>'), digits (from '<code>0</code>' to '<code>9</code>')
		555	or hyphens ('<code>-</code>'). See Rec. ITU-T X.680 \| ISO/IEC 8824-1,
		556	clause 32, for more details.<br>In <a href="name-forms.htm">some cases</a>, the identifier has been
		557	standardized and can be used alone (without the associated number)
		558	in the ASN.1 notation. The number can always be used alone. This web
		559	site will issue an error message if you are trying to display an OID
		560	using an invalid ASN.1 notation.<br>An OID is semantically an ordered list of OID components (number only,
		561	or identifier followed by a number between parentheses, or identifier
		562	alone in <a href="name-forms.htm">some cases</a>). Starting with the
		563	root of the OID tree, each OID component identifies an arc in the
		564	OID tree. The last OID component identifies an arc leading to a node
		565	to which an object has been assigned. It is this object which is identified
		566	by the OID.<br>Example: <a href="/get/2.5.4.49"><code>{joint-iso-itu-t ds(5) attributeType(4)
		567	distinguishedName(49)}</code></a> where <a href="/get/2"><code>joint-iso-itu-t</code></a>
		568	is a <a href="name-forms.htm">standardized identifier</a> which can
		569	appear alone, <i>i.e.</i>, without its associated number.<br>(See also <a href="#14">question 14</a> for the dot notation and <a href="#iri">question
		570	28</a> about the OID-IRI notation.) <br><br></div>
		571	</li>
		572	<li>
		573	<div class="question">
		574	How is the entire registration tree managed?<a name="18"></a><a name="management"></a>
		575	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		576	</div>
		577	<div class="answer">
		578	The management of the entire registration tree is accomplished by
		579	a process of delegation of authority. In this process the registration
		580	authority responsible for a given arc in the registration tree may
		581	partition that naming-domain. In doing so, it may or may not delegate
		582	the registration responsibility for the naming-domain formed by each
		583	partition to a subordinate Registration Authority. The naming of a
		584	partition does not necessarily imply authority to register objects
		585	under that partition. This delegation of registration responsibility
		586	can be applied repeatedly with a subordinate registration authority
		587	partitioning further the naming domain for which it is responsible
		588	and delegating responsibility for those partitions to registration
		589	authorities subordinate to it.<br>The registration authority responsible for a given naming-domain must
		590	assign a name to the partition of that naming-domain that a given
		591	sub-authority will manage. The name assigned shall be globally unambiguous,
		592	and shall be concatenated as a prefix to all names assigned by that
		593	sub-authority. The repeated application of this process through a
		594	hierarchy of registration agents ensures the generation of unambiguous
		595	names.<br>An organization, a standard or an automated facility can be the registration
		596	authority for more than one partition of a naming-domain (see also
		597	<a href="#11">questions 11 and 12</a> for how country arcs are managed).<br><br></div>
		598	</li>
		599	<li>
		600	<div class="question">
		601	Which features are offered by this repository?<a name="19"></a><a name="features"></a>
		602	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		603	</div>
		604	<div class="answer">
		605	The <a href="display-example.htm">description page</a> for each OID
26	daniel-mar	606	offers the following features:
2	daniel-mar	607	<ul type="disc">
		608	<li>
		609	have a synthetic <a href="/cgi-bin/display?tree=">graphical
26	daniel-mar	610	view</a> of the tree (click on the
		611	<img src="images/mm.gif" width="19" height="18" alt="Folding the subtree">
		612	and
		613	<img src="images/pm.gif" width="19" height="18" alt="Unfolding the subtree">
		614	icons to fold and unfold arcs);
2	daniel-mar	615	</li>
		616	<li>display the description of another OID (the "Go" button);</li>
		617	<li>
		618	use the "remote control" to display the description
		619	of:
		620	<ul>
		621	<li>
		622	the parent OID (i.e. the OID at the immediate upper level
		623	in the OID tree),
		624	</li>
		625	<li>
		626	the previous or next sibling OID (i.e. OID at the same
		627	level in the OID tree),
		628	</li>
		629	<li>
		630	the very first or very last sibling OID (i.e. OID with the
		631	lowest or greatest number at the same level in the OID tree),
		632	or
		633	</li>
		634	<li>
		635	the first child OID (the OID with the lowest number at
		636	the immediate lower level in the OID tree);
		637	</li>
		638	</ul>
		639	</li>
		640	<li>
		641	submit a description of a child OID under the current OID (see
		642	also <a href="#syntax-rules">question 20</a>): After putting down
		643	some information (description of the OID, its registrant...),
		644	the registrant of the OID (if known), the registrant of the parent
		645	OID (if known) and the OID repository administrator will be automatically
		646	asked by email to review and validate your submission. Note that
		647	the description page of the newly created OID will only be available
		648	after validation;
		649	</li>
		650	<li>
		651	submit a description of a sibling OID, i.e. an OID at the same
		652	level as the current OID (see also <a href="#syntax-rules">question
		653	20</a>);
		654	</li>
		655	<li>
		656	propose modifications of the description of the current OID:
		657	these modifications will have to be validated by the registrant
		658	of the OID (if known), the registrant of the parent OID (if known)
		659	and the OID repository administrator (who will all be automatically
		660	informed by e-mail) before they get published;
		661	</li>
		662	<li>
		663	do a <a href="basic-search.htm">quick search</a> of the entire
		664	OID repository by searching for a particular string in all attributes;
		665	</li>
		666	<li>
20	daniel-mar	667	do an <a href="search.htm">advanced search</a> of the entire
2	daniel-mar	668	OID repository by searching for a particular value for each description
		669	attribute or even by using regular expressions.
		670	</li>
		671	</ul>
		672	Other features are available from the <a href="index.htm">main page</a> of
		673	the OID repository:
		674	<ul>
		675	<li>
		676	display an <a href="/cgi-bin/display?a=random">OID description
		677	randomly</a>;
		678	</li>
		679	<li>
		680	display the <a href="/cgi-bin/display?a=count_nodes">number
		681	of OIDs</a> in the repository as well as statistics about how
		682	many OID descriptions were added or modified over the past 12
		683	months;
		684	</li>
		685	<li>
		686	add the description of a given OID (see also <a href="#syntax-rules">question
		687	20</a>);
		688	</li>
		689	<li>
		690	<a href="submit.htm">submit</a> many OIDs to the database by
		691	describing them in an XML file.<br><br></li>
		692	</ul>
		693	</div>
		694	</li>
		695	<li>
		696	<div class="question">
		697	What are the syntax rules to enter information about OIDs through the web interface?<a name="20"></a><a name="syntax-rules"></a>
		698	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		699	</div>
		700	<div class="answer">
		701	When adding information about an OID into the OID repository, non-ASCII
		702	characters such as accentuated letters are allowed in most fields
		703	("Description", "Information", registrant "First
		704	name", "Last name" and "Address"). The software
20	daniel-mar	705	will replace them by their equivalent <a href="https://www.w3.org/MarkUp/html-spec/html-spec_13.html#SEC106">HTML
2	daniel-mar	706	code</a>.<br>The following HTML tags are allowed in the "Description",
		707	"Information" and "Address" fields: <code><a></code>,
		708	<code><br/></code>, <code><code></code>, <code><em></code>,
		709	<code><img></code>, <code><li></code>, <code><ol></code>,
		710	<code><strong></code>, <code><sub></code>, <code><sup></code>
		711	and <code><ul></code>. Use of <code><br></code> or <code><br/></code>
		712	is not mandatory to break lines because any newline character will
		713	automatically be replaced with <code><br/></code> by the software.<br>The description should be as short as possible (usually, not more
		714	than one line), limited to what is identified by the OID (hence no
		715	need to use expressions like "OID for", "OID identifying", "Root OID
		716	for", "Arc for", "This OID describes", etc.) and written in such a
		717	way that is easily understandable by any user of the OID repository.<br><br></div>
		718	</li>
		719	<li>
		720	<div class="question">
		721	Which information is necessary to apply for an OID?<a name="21"></a><a name="oid-info"></a>
		722	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		723	</div>
		724	<div class="answer">
20	daniel-mar	725	According to clause 8.2 f of <a href="https://www.itu.int/rec/T-REC-X.660/en">Recommendation
2	daniel-mar	726	ITU-T X.660 \| ISO/IEC 9834-1</a>, the registration record for an OID
20	daniel-mar	727	shall include at least:<br>a) the <a href="#guidelines">definition</a> of the object (when the registration authority of
2	daniel-mar	728	the parent OID performs a technical role, it checks that the objet
		729	can be registered under the parent OID);<br>b) when applicable, the identifier (beginning with a lowercase letter)
15	daniel-mar	730	assigned to the object (in addition to the unique number);<br>c) the name and contact information of the organization that proposed
2	daniel-mar	731	the entry (usually it is the "<a href="#registration-authorities">First
15	daniel-mar	732	registration authority</a>" for the requested OID);<br>d) the dates of submission/registration.<br><br></div>
2	daniel-mar	733	</li>
		734	<li>
		735	<div class="question">
		736	Is there a particular OID that can be used for documenting
		737	examples of object identifiers?<a name="22"></a><a name="example"></a>
		738	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		739	</div>
		740	<div class="answer">
		741	<a href="/get/2.999">{joint-iso-itu-t(2) example(999)}</a> (or <a href="/get/2.999">2.999</a>)
		742	can be used by anyone, without any permission, for the purpose of
		743	documenting examples of object identifiers (in the same way as "example.com"
3	daniel-mar	744	is defined in <a href="https://datatracker.ietf.org/doc/html/rfc2606">IETF RFC
2	daniel-mar	745	2606</a> as an example for web sites). <br><br></div>
		746	</li>
		747	<li>
		748	<div class="question">
		749	What is the difference between the first and current Registration Authorities
		750	that appear in the description of some OIDs? What is their duty?<a name="23"></a><a name="registration-authorities"></a>
		751	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		752	</div>
		753	<div class="answer">
		754	A <em>Registration Authority</em> (RA) is responsible for allocating
		755	child arcs to the OID for which it manages. It ensures that an integer
		756	is used once among the subsequent arcs (child OIDs). As much as possible,
		757	it avoids the same identifier (beginning with a lowercase letter)
		758	being used for multiple sub-arcs. It also keeps a record of information
		759	(name of a contact person, postal address, telephone and fax numbers,
		760	email address, etc.) about the RA for each child OID and delegates
		761	its duty to each 'child' RA. Such information can be stored in the
		762	OID repository but it is important to understand that an OID first
		763	need to be <em>officially</em> allocated by an RA before it can be
		764	described on this website which is not an official RA, but a <em>repository</em>
		765	of information about existing OIDs.<br>The <em>first Registration Authority</em> of an OID is the very first
		766	person or company to whom the OID was allocated by the RA of the superior
20	daniel-mar	767	OID. According to <a href="https://www.itu.int/rec/T-REC-X.660/en">Recommendation
2	daniel-mar	768	ITU-T X.660 \| ISO/IEC 9834-1</a>,<!-- clause 9.2.f.a --> the first
		769	RA can't be changed (if the responsibility is transfered to someone
		770	else, the information is recorded in the "Current Registration
		771	Authority" section, without changing the "First Registration
		772	Authority" section).<br>By default, if the OID has recently been allocated, the Current RA
		773	is the First RA. So, if you are <a href="#4">entering information
		774	in the OID repository</a>, please fill only the "First Registration
		775	Authority" section, and don't copy the same information in the
		776	"Current Registration Authority" section).<br>When someone or an organization takes over the duty from the First
		777	RA, the relevant information is indicated in the "Current Registration
		778	Authority" section without changing the "First Registration
		779	Authority" section.<br><br></div>
		780	</li>
		781	<li>
		782	<div class="question">
		783	What constraints are imposed to OIDs used in SNMP MIBs (Management Information Bases)?<a name="24"></a><a name="mib"></a>
		784	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		785	</div>
		786	<div class="answer">
		787	The constraints are gathered in sections 4.6.5, 4.6.6, and Appendix
3	daniel-mar	788	D of IETF <a href="https://datatracker.ietf.org/doc/html/rfc4181">RFC 4181</a>
		789	(updated by <a href="https://datatracker.ietf.org/doc/html/rfc4841">RFC 4841</a>)
15	daniel-mar	790	which makes references to IETF <a href="https://datatracker.ietf.org/doc/html/rfc2578">RFC
3	daniel-mar	791	2578</a>, sections 3.5, 3.6, 5.6, 7.10, and <a href="https://datatracker.ietf.org/doc/html/rfc3416">RFC
2	daniel-mar	792	3416</a>, section 4.1.<br>
15	daniel-mar	793	- According to IETF <a href="https://datatracker.ietf.org/doc/html/rfc2578">RFC 2578</a>, section 3.5, all OIDs are limited to 128 child OIDs and each OID has a maximum (integer) value of 2<sup>32</sup>-1 (<code>4294967295</code>).<br>
		794	- The last arc of an OID assigned to any object (be it table, row, column, or scalar) must not be equal to 0.<br>- In some cases, a final arc 0 is used to translate between SNMPv1 and SNMPv2 notification parameters as explained in IETF <a href="https://datatracker.ietf.org/doc/html/rfc2576">RFC 2576</a>, section 3.<br>One example of a MIB module whose OID assignments follow the recommended scheme is the <code>POWER-ETHERNET-MIB</code> defined in <a href="https://datatracker.ietf.org/doc/html/rfc3621">RFC 3621</a>.<br>MIBs use a notation like "<code>.2.999</code>" where the leading dot shows that this OID is absolute while "<code>2.999</code>" might be considered as a relative OID by some tools which would then add a root OID in front of it.<br><br></div>
2	daniel-mar	795	</li>
		796	<li>
		797	<div class="question">
		798	Is there a way to look up an OID in the OID repository from my web browser?<a name="25"></a><a name="lookup"></a>
		799	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		800	</div>
		801	<div class="answer">
20	daniel-mar	802	- If you're using <img src="images/firefox-icon.png" width="16" height="16" alt="[Firefox Icon]"><a href="https://www.mozilla.org/firefox/">Mozilla Firefox</a> or <img src="images/mozilla-icon.png" width="16" height="16" alt="[Mozilla Icon]"><a href="https://www.seamonkey-project.org">Mozilla SeaMonkey</a>
		803	or <img src="images/google-chrome.ico" width="16" height="16" alt="[Chrome Icon]" border="0"><a href="https://www.google.com/chrome/">Google Chrome</a>, an <a href="https://mycroft.mozdev.org/search-engines.html?name=oid+resolver&skipcache=yes">OpenSearch
2	daniel-mar	804	Plugin</a> (a.k.a. search engine) allows to display information about
3	daniel-mar	805	an OID when an ASN.1 notation, dot notation, <a href="https://datatracker.ietf.org/doc/html/rfc3061">URN</a> notation
2	daniel-mar	806	or <a href="#iri">OID-IRI</a> notation is entered in the search bar
20	daniel-mar	807	at the top-right.<br><!-- - If you're using <a href="https://www.mozilla.org/products/thunderbird/">Mozilla
		808	Thunderbird</a>, <img src="images/firefox-icon.png" width="16" height="16" alt="[Firefox Icon]"><a href="https://www.mozilla.org/products/firefox/">Mozilla Firefox</a>
		809	or <img src="images/mozilla-icon.png" width="16" height="16" alt="[Mozilla Icon]"><a href="https://www.mozilla.org/projects/seamonkey/">Mozilla SeaMonkey</a>
		810	(formerly known as Mozilla Application Suite), the <a href="https://dictionarysearch.mozdev.org">DictionarySearch
2	daniel-mar	811	add-on</a> is easy to configure so that you can display information
		812	about an OID by right-clicking on its selection:<br><ul>
		813	<li>install the DictionarySearch extension corresponding to your
20	daniel-mar	814	tool from <a href="https://dictionarysearch.mozdev.org">https://dictionarysearch.mozdev.org</a>;</li>
2	daniel-mar	815	<li>in the "Tools" menu of your tool, select the "Extensions"
		816	item;</li>
		817	<li>highlight the line for DictionarySearch, then click on the "Options"
		818	button;</li>
		819	<li>add a new Dictionary with the following information (this will
		820	display the description of the selected OID in dot notation; it
		821	doesn't work well for a selected OID in ASN.1 notation because
26	daniel-mar	822	the closing parentheses are removed for whatever reason):<br><em>Text</em>: <code>Search for OID "$"</code><br><em>Access key</em>: <code>O</code><br><em>URL</em>: <code>http://oid-info.com/cgi-bin/display?oid=$&a=display</code></li>
2	daniel-mar	823	<li>This other new "Dictionary" may also be useful (it
26	daniel-mar	824	will display a tree for the selected OID in dot notation):<br><em>Text</em>: <code>Display tree for OID "$"</code><br><em>Access key</em>: <code>T</code><br><em>URL</em>: <code>http://oid-info.com/cgi-bin/display?oid=$&a=tree</code>
2	daniel-mar	825	</li>
		826	</ul> --> - See also <a href="#8">question 8</a>.<br><br></div>
		827	</li>
		828	<li>
		829	<div class="question">
		830	What is a leaf OID? What is a frozen OID?<a name="26"></a><a name="leaf"></a>
		831	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		832	</div>
		833	<div class="answer">
		834	These are not standardized concepts. In case an OID is a <em>leaf</em>
		835	in the OID repository, no child OIDs can be allocated under that OID.
		836	In case an OID is <em>frozen</em> in the OID repository, no more child
		837	OIDs can be created in addition to the existing ones. In both cases,
		838	the system does not accept the creation of child OIDs. The status
		839	is also mentioned on the web page that describes an OID (see example
		840	for a <a href="/get/0.0.2">leaf OID</a> and for a <a href="/get/0">frozen
		841	OID</a>).<br>To report that an OID is a leaf or is frozen, please <a href="#modify">suggest
		842	a modification</a> for this OID and use the "Comments" box
		843	at the bottom.<br><br></div>
		844	</li>
		845	<li>
		846	<div class="question">
		847	What is an orphan OID?<a name="27"></a><a name="orphan"></a>
		848	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		849	</div>
		850	<div class="answer">
		851	This is not a standardized concept but this term is used to qualify
		852	an OID that is described in the OID repository, but some of its parent
		853	OIDs are not described in the OID repository. This does not mean that
		854	these unknown parent OIDs do not exist (actually they do exist because
		855	an OID can only be allocated by the Registration Authority of its
		856	parent OID). However the user who submitted the description of this
		857	OID has no knowledge of how to describe these parent OIDs.<br><!-- This is useful in cases such as:<br>- you have found the description of an OID somewhere on the web or
		858	in a document, but you don't know how to describe all arcs along the
		859	path;<br>- you have a bunch of OIDs to submit to the OID repository, so you
		860	can submit them in any order because there is no obligation to submit
		861	the father OID first.<br>-->
		862	Orphan OIDs are not visible when one
		863	<a href="/cgi-bin/display?tree=">walks down the OID tree</a>. However,
		864	they are <a href="display-example.htm">displayed</a> when one asks
		865	for the description of a particular OID. <em>Orphan grandchild OIDs</em>
		866	(<em>i.e.</em>, OIDs for which we have a description as well as a
		867	description of their grandparent OID, but no description of their
		868	parent OID) are accessible from the <a href="display-example.htm">description
		869	page</a> of their grandparent OID.<br><br></div>
		870	</li>
		871	<li>
		872	<div class="question">
		873	What is an OID-IRI (Internationalized Resource Identifier)?<a name="28"></a><a name="iri"></a>
		874	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		875	</div>
		876	<div class="answer">
		877	Historically, OIDs could only be denoted in <a href="#14">dot notation</a>
		878	(<em>e.g.</em>, <code>2.27</code>) or in <a href="#17">ASN.1 notation</a>
		879	(<em>e.g.</em>, <code>{joint-iso-itu-t(2) tag-based(27)}</code>) where
		880	only ASCII identifiers are allowed. The need was identified for a
		881	human-friendly notation which would not be limited to latin alphabets
20	daniel-mar	882	and would encompass the diversity of <a href="https://www.unicode.org">Unicode
2	daniel-mar	883	alphabets</a>.<br>An OID-IRI (a.k.a. international OID) is a string of slash-separated
		884	Unicode labels from the root of the OID tree, which unambiguously
		885	identifies a node in the OID tree (e.g., "<a href="/get//Joint-ISO-ITU-T/Example"><code>/Joint-ISO-ITU-T/Example</code></a>").<br>A Unicode label is a case-sensitive string of Unicode characters (except
		886	the <code>SPACE</code> character). Just as an OID node can have multiple
		887	identifiers in ASN.1 notation, it can have multiple Unicode labels
		888	(this allows backwards-compatibility when a company changes its name,
		889	for example). Each OID node has a default Unicode label which is its
		890	number (<em>e.g.</em>, "<a href="/get//2/999"><code>/2/999</code></a>").<br>In order to support names of OIDs in multiple languages, an OID can
		891	have multiple Unicode labels, giving rise to a need to transform a
		892	path using Unicode labels into a canonical form of purely numerical
		893	labels to identify the OID. This is handled by the <a href="introduction.htm#ors">OID
		894	Resolution System</a>.<br>A <em>long arc</em> is a particular kind of Unicode label which identifies
		895	an OID that is not immediately beneath the root of the OID tree. For
		896	example, OID <code>{joint-iso-itu-t(2) example(999)}</code> has a
		897	long arc named "<code>Example</code>" allowing OID-IRI "<code><a href="/get//Example">/Example</a></code>"
		898	which is shorter than OID-IRI "<code><a href="/get//Joint-ISO-ITU-T/Example">/Joint-ISO-ITU-T/Example</a></code>".
		899	Long arcs are only allowed for OIDs under the <code>joint-iso-itu-t(2)</code>
20	daniel-mar	900	top-level arc (see the <a href="https://www.itu.int/go/X660">register of
		901	long arcs)</a>.<br>The <a href="https://www.itu.int/rec/T-REC-X.680/en">ASN.1 standard</a>
2	daniel-mar	902	specifies an <code>OID-IRI</code> type for exchanging OID-IRI values
		903	between machines.<br><br></div>
		904	</li>
		905	<li>
		906	<div class="question">
		907	What are the duties of a Registration Authority?<a name="29"></a>
		908	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		909	</div>
		910	<div class="answer">
		911	Guidance is given in sections 8.2 (Operation), 9 (registration procedures)
20	daniel-mar	912	and 11 (recommended fee structure) of <a href="https://www.itu.int/rec/T-REC-X.660/en">Recommendation
2	daniel-mar	913	ITU-T X.660 \| ISO/IEC 9834-1</a>.<br>The open-source database system <a href="https://oidplus.viathinksoft.com/oidplus/">OIDplus</a>
		914	from ViaThinkSoft can be used by Registration Authorities to manage
		915	their OIDs. It includes a feature to export data into an <a href="submit.htm">XML
		916	document that can then be uploaded to this OID repository</a>.<br><br></div>
		917	</li>
		918	<li>
		919	<div class="question">
		920	Are there size limitations for OID encoding?<a name="30"></a><a name="size-limitations"></a>
		921	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		922	</div>
		923	<div class="answer">
		924	The <a href="standards.htm">OID standards</a> have no limit whatsoever about the depth of an OID in the OID tree (i.e., number of arcs) and the size of the integer associated to each OID arc. At the moment, the <a href="/get/1.3.6.1.4.1.1248.1.1.2.1.3.21.69.112.115.111.110.32.83.116.121.108.117.115.32.80.114.111.32.52.57.48.48">longest OID</a> described in the OID repository has 171 chars and 34 arcs. The <a href="/get/2.25.336702412625001560652410773774433371419">greatest number</a> for an OID arc has 39 digits. However, there are constraints for OIDs used in SNMP Management Information Bases (<a href="#mib">see question 24</a>) and some tools may have size limitations (or bugs):<br>- The <a href="https://lapo.it/asn1js/">ASN.1 JavaScript decoder at
20	daniel-mar	925	lapo.it</a>, <a href="https://www.bouncycastle.org">Bouncy Castle Crypto
2	daniel-mar	926	APIs</a>, OpenSSL (version 0.9.8o, 1 Jun 2010) and the built-in Java
		927	class "<code>org.ietf.jgss.Oid</code>" can handle <a href="/get/2.25">UUIDs
		928	used as OIDs</a>.<br>- Windows CryptoAPI Shell Extension (tested with Windows XP and Windows
		929	7) cannot handle <a href="/get/2.25">UUIDs used as OIDs</a>: The maximum
		930	useable OID value in Windows is 2<sup>64</sup>-1 (e.g., <code>2.999.18446744073709551615</code>).
		931	Windows will show whitespace when any higher value occurs.<br>- Mozilla software cannot handle <a href="/get/2.25">UUIDs used as
		932	OIDs</a>: The maximum useable OID value in Mozilla software is 2<sup>32</sup>-1
		933	(e.g., <code>2.999.4294967295</code>). The program will show "Unknown"
		934	when an arc contains a higher value (e.g., <code>{2 999 Unknown 0}</code>).
		935	<br>- Mac OS X cannot handle OIDs of the form <code>2.<em>n</em></code>
		936	where <code><em>n</em></code> > 47 (i.e., it wrongly decodes OIDs
20	daniel-mar	937	which need more than one octet in the first two arcs). <br>More details can be found in <a href="https://misc.daniel-marschall.de/asn.1/oid_facts.html">Daniel
2	daniel-mar	938	Marschall's study about OID encoding and size limitations</a>. Daniel's
20	daniel-mar	939	<a href="https://misc.daniel-marschall.de/asn.1/oid-converter/online.php">DER
2	daniel-mar	940	encoder</a> can also help in your testing.<br><br></div>
		941	</li>
		942	<li>
		943	<div class="question">
		944	Are there binary encoders/decoders for OIDs?<a name="31"></a>
		945	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		946	</div>
		947	<div class="answer">
20	daniel-mar	948	See for example (non-exhaustive list):<strong><br></strong>- OSS Nokalva's online <a href="https://asn1.io">ASN.1
2	daniel-mar	949	playground</a> encodes/decodes OIDs in any encoding rule (BER, DER,
		950	PER, UPER, XER) with the following schema:<br><code>     OID-Module DEFINITIONS ::= BEGIN<br>       OID ::= OBJECT IDENTIFIER<br>     END</code><br>  The OID is provided in ASN.1 notation in the "Data:
20	daniel-mar	951	Encode" box as follows:<br><code>     oid OID ::= {2 999}</code><br>- Daniel Marschall's online <a href="https://misc.daniel-marschall.de/asn.1/oid-converter/online.php">DER
		952	encoder/decoder</a> (for PHP and C);<br>- <a href="https://bouncycastle.org">The Legion of the Bouncy Castle</a>'s
		953	API for Java and C#;<br>- <a href="https://www.wireshark.org">Wireshark</a>'s subtool for ASN.1.<br>See also <a href="https://misc.daniel-marschall.de/asn.1/oid_facts.html#chap4">Daniel
2	daniel-mar	954	Marschall's software compatibility analysis for large OIDs</a>.<br><br></div>
		955	</li>
		956	<li>
		957	<div class="question">
		958	Does this web site use cookies?<a name="32"></a><a name="cookies"></a>
		959	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		960	</div>
		961	<div class="answer">
		962	You can set up your browser to reject cookies: Disabling their use
		963	will not materially impact on your interaction with this website.<br>Only users who have submitted information on OIDs (description of
		964	a new OID or proposed modifications to an existing OID) have a unique
		965	cookie placed on their machine with their first name, last name and
		966	email address, so that the "submitter" section is automatically
		967	filled the next time they submit information. This cookie is not used
		968	to track your use of the OID repository.<br>The <a href="/helper">OID helper</a> chatbot is (externally) hosted
20	daniel-mar	969	by <a href="https://pandorabots.com/botmaster/en/~121e02c2b4d4270afe6afac6~/faq">Pandorabots</a>
2	daniel-mar	970	which normally tracks individual conversations by placing a cookie
		971	on your browser, in order to offer contextual answers to your questions
		972	(please check <a href="https://home.pandorabots.com/policies.html#privacy-policy">Pandorabots'
		973	privacy policy</a>). However, if your browser is not setup to accept
		974	cookies, an alternative mechanism is used through a hidden variable
		975	in the HTML form.<br><br></div>
		976	</li>
		977	<li>
		978	<div class="question">
		979	How does this web site protect users' privacy?<a name="33"></a><a name="privacy"></a>
		980	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
		981	</div>
		982	<div class="answer">
		983	The purpose of this section (updated on 24 Jan 2019) is to inform
		984	you about the way your personal data is handled on this web site.
		985	By providing your personal data to this web site, you acknowledge
		986	and consent to the collection, use and disclosure of your personal
		987	data for a legitimate interest as explained hereunder. This web site
		988	never sells, leases or rents your personal data.<br>Only users who have submitted information on OIDs (description of
		989	a new OID or proposed modifications to an existing OID) have personal
		990	data stored in the OID repository database. The only reason to keep
		991	such information is to inform them when the OID description is validated
		992	or modified by the OID repository administrator, or when modifications
		993	are suggested by another user (see also <a href="#cookies">question
		994	32 about cookies</a>). This information is not publicly disclosed
		995	on the web site. (Note, however, that it may be sent by email to the
		996	<a href="#registration-authorities">(current or first) registration
		997	authority</a> of the OID and of its parent OID, when they are known).<br>Only those users who are the contact of a <a href="#registration-authorities">(current
		998	or first) registration authority</a> for an OID and have not ticked
		999	the box "<i>Protect the privacy of the Registration Authority
		1000	by not displaying the contact information on the web site</i>"
		1001	have their personal data (email address, postal address, phone number)
		1002	publicly visible on the web site. (Note, however, that even when the
		1003	"privacy" box is ticked, any user of this web site can <a href="/cgi-bin/manage?a=get-info">receive
		1004	by email a copy of such data</a> so as to be able to contact the registration
		1005	authority of an OID; such requests are recorded). These users are
		1006	automatically notified by email when information about them is entered
		1007	and can request deletion of such data.<br>In some cases, your personal data appears in the OID repository because
		1008	it is publicly available on another web site (e.g., <a href="https://www.iana.org/assignments/enterprise-numbers/enterprise-numbers">IANA
		1009	enterprise numbers</a>).<br>To check if personal data related to you appears in the OID repository,
20	daniel-mar	1010	please use the <a href="search.htm">advanced search</a>. You can
2	daniel-mar	1011	also <a href="/cgi-bin/manage?a=get-personal-data">get a copy</a>
		1012	of all personal data appearing in the OID repository. In any case,
		1013	your personal data is never used for sending any kind of publicity
		1014	to you.<br>A log of all modifications made to an OID is also kept (hence your
		1015	personal data may appear in that log) but it is not public and would
		1016	only be used by the OID repository administrator to explain or undo
		1017	changes if needed.<br>For any other question related to data protection or to request the
		1018	rectification or erasure of your personal data, you can <a href="/helper">contact
		1019	the webmaster</a>. Repetitive, disproportionate or impracticable requests
		1020	may be rejected.
15	daniel-mar	1021	<br><br></div>
		1022	</li>
		1023
		1024
		1025
		1026	<li>
		1027	<div class="question">
		1028	What are the guidelines to adequately describe an OID in this OID repository?<a name="34"></a><a name="guidelines"></a>
		1029	<a href="#top"><img src="images/page_top_fleche.png" width="27" height="17" border="0"></a>
2	daniel-mar	1030	</div>
15	daniel-mar	1031	<div class="answer">
		1032	The following rules are followed by the OID repository administrator to validate OID descriptions:
		1033	<ul>
		1034	<li>The description shall be as short as possible (usually, not more than one line) and focus on <em>what</em> (i.e., which object) is identified by the OID. The description shall not be a sentence (with a verb). Consequently, the description does not end up with a full stop "." (except when the full stop is part of an abbreviation). See also the <a href="#syntax-rules">syntax rules</a>.</li>
		1035	<li>The description should be easily understandable by any user of the OID repository. Substantives should not be put one after the other without inserting small words like "for", "of", etc. This helps understanding the description and avoids ambiguities when translating to other languages.</li>
		1036	<li>Useless expressions like "OID for", "OID identifying", "Root OID for", "Top arc for", "Arc for", "This OID describes", "This arc describes", etc., are forbidden.</li>
		1037	<li>Words are not capitalized (contrarily to what is usually done for paper or book titles in English) except for an abbreviation or acronym which is put between parentheses after the expression that defines it (with each letter of the abbreviation being capitalized in its definition), e.g., Meaning of My Abbreviation (MMA).</li>
		1038	<li>Any text (e.g., how it is used, how child OIDs are allocated, etc.) which is not related to <em>what</em> is identified by the OID shall be moved to the "Information" part. Any text which can be assimilated to a publicity or a company description shall be avoided (a URL can be associated to the company name).</li>
		1039	</ul>
		1040	</div>
2	daniel-mar	1041	</li>
15	daniel-mar	1042
		1043
2	daniel-mar	1044	</ol>
		1045
		1046	</td>
		1047	</tr>
		1048	</table>
		1049
		1050	</div>
		1051
		1052	<div class="clear"></div>
		1053	</div>

Subversion Repositories oidinfo_new_design

oidinfo_new_design/trunk/faq.raw.htm – Rev 28