Indicators and subfield codes
No information provided
2 Remote login (Telnet)
7 Method specified in subfield ‡2
No information provided
1 Version of resource
2 Related resource
8 No display constant generated
‡a Host name (R)
‡b Access number (R)
‡c Compression information (R)
‡d Path (R)
‡f Electronic name (R)
‡h Processor of request (NR)
‡i Instruction (R)
‡j Bits per second (NR)
‡k Password (NR)
‡l Logon (NR)
‡m Contact for access assistance (R)
‡n Name of location of host (NR)
‡o Operating system (NR)
‡p Port (NR)
‡q Electronic format type (NR)
‡r Settings (NR)
‡s File size (R)
‡t Terminal emulation (R)
‡u Uniform Resource Identifier (R)
‡v Hours access method available (R)
‡w Record control number (R)
‡x Nonpublic note (R)
‡y Link text (R)
‡z Public note (R)
‡2 Access method (NR)
‡3 Materials specified (NR)
‡8 Field link and sequence number (R)
Field definition and scope
This field contains the information required to locate electronic information. The information identifies the electronic location containing the resource or from which it is available. It also contains information needed to retrieve the resource by the access method identified by the first indicator position. The relationship of the electronic location and access information in field 856 to the resource identified by the record as a whole is identified by the second indicator. The information contained in this field is sufficient to allow for the electronic transfer of a file, subscription to an electronic journal, or logon to an electronic resource. In some cases, only unique data elements are recorded which allow the user to access a locator table on a remote host containing the remaining information needed to access the resource.
Field 856 is repeated when the location data elements vary (subfields ‡a, ‡b, ‡d) and when more than one access method may be used. It is also repeated whenever the electronic filename varies (subfield ‡f), except when a single intellectual work is divided into different parts for online storage or retrieval.
Additional information and description of the use of field 856 (Electronic Location and Access) is in OCLC Bibliographic Formats and Standards.
Guidelines for applying content designations
First Indicator - Access method
The first indicator position contains a value that defines the access method to the electronic resource. If the resource is available by more than one access method, the field is repeated with data appropriate to each method. The methods defined are the main TCP/IP (Transmission Control Protocol/Internet Protocol) protocols.
When recording a URL in subfield ‡u the value corresponds to the access method (URL scheme), which is also the first element in the URL string.
- No information provided
Value indicates that no information about access method is provided. This value is used when subfield ‡u contains a URN and there is no URL recorded. When subfield ‡u contains a URL and the subfield is repeated with a URN, the indicator value for the appropriate access method of the URL is given.
856 ‡u urn:doi:10.1000/100
0 - Email
Value 0 indicates that access to the electronic resource is through electronic mail (email). This access includes subscribing to an electronic journal or electronic forum through software intended to be used by an email system.
856 0 ‡u mamilto:firstname.lastname@example.org ‡i ejap subscription
1 - FTP
Value 1 indicates that the access to the electronic resource is through the File Transfer Protocol (FTP).
856 1 ‡u ftp://path.net/pub/docs/urn2urc.ps
2 - Remote login (Telnet)
Value 2 indicates that access to the electronic resource is through remote login (Telnet).
856 2 ‡u telnet://pucc.princeton.edu ‡n Princeton University, Princeton, N.J.
3 - Dial-up
Value 3 indicates that access to the electronic resource is through a conventional telephone line (dial-up). Additional information in subfields of the record may enable the user to connect to the resource.
856 3 locis.loc.gov ‡b 188.8.131.52 ‡m email@example.com ‡t 3270 ‡t line mode (e.g., vt100) ‡v M-F 6:00 a.m.-21:30 p.m. USA EST, Sat. 8:30-17:00 USA
EST, Sun. 13:00-17:00 USA EST
4 - HTTP
Value 4 indicates that access to the electronic resource is through the Hypertext Transfer Protocol (HTTP).
856 4 0 ‡3 b&w film copy neg. ‡d dag ‡f 3d01926 ‡2 file
7 - Method of specified in subfield ‡2
Value 7 indicates that access to the electronic resource is through a method other than the defined values and for which an identifying code is given in subfield ‡2 (Source of access).
856 7 ‡3 b&w film copy neg. ‡d dag ‡f 3d01926 ‡2 file
Second Indicator - Relationship
The second indicator position contains a value that identifies the relationship between the electronic resource at the location identified in field 856 and the item described in the record as a whole. Subfield ‡3 is used to provide further information about the relationship if it is not a one-to-one relationship.
- No information provided
Value indicates that no information is provided about the relationship of the electronic resource to the bibliographic item described by the record.
0 - Resource
Value 0 indicates that the electronic location in field 856 is for the same resource described by the record as a whole. In this case, the item represented by the bibliographic record is an electronic resource. If the data in field 856 relates to a constituent unit of the resource represented by the record, subfield ‡3 is used to specify the portion(s) to which the field applies. The display constant Electronic resource: may be generated.
856 4 0 ‡u http://lcweb.loc.gov/catdir/semdigdocs/seminar.html
1 - Version of resource
Value 1 indicates that the location in field 856 is for an electronic version of the resource described by the record. In this case, the item represented by the bibliographic record is not electronic but an electronic version is available. If the data in field 856 relates to a constituent unit of the resource represented by the record, subfield ‡3 is used to specify the portion(s) to which the field applies. The display constant Electronic version: may be generated.
856 4 1 ‡u http://muse.jhu.edu/journals/american%5Fquarterly/
2 - Related resource
Value 2 indicates that the location in field 856 is for an electronic resource that is related to the bibliographic item described by the record. In this case, the item represented by the bibliographic record is not the electronic resource itself. Subfield ‡3 can be used to further characterize the relationship between the electronic item identified in field 856 and the item represented by the bibliographic record as a whole. The display constant Related electronic resource: may be generated.
856 4 2 ‡3 Finding aid ‡u http://lcweb2.loc.gov/ammem/ead/jackson.sgm
8 - No display constant generated
Value 8 specifies that no display constant is to be generated.
‡a - Host name
Subfield ‡a contains the fully qualified domain (host name) of the electronic location. It contains a network address which is repeated if there is more than one address for the same host.
‡b - Access number
Subfield ‡b contains the access number associated with a host. It can contain the Internet Protocol (IP) numeric address if the item is an Internet resource, or a telephone number if dial-up access is provided through a telephone line. This data may change frequently and may be generated by the system, rather than statically stored. Subfield ‡b may be repeated if all the other information in the field applies.
‡c - Compression information
Subfield ‡c contains information about the compression of a file. If a specific program is required to decompress the file, it is noted here. The subfield may be repeated if two compression programs are used, noting the latest compression first.
‡d - Path
Subfield ‡d contains the path, the series of logical directory and subdirectory names that indicate where a file is stored. The filename itself is recorded in subfield ‡f. This may be a surrogate path leading the user to the host where complete and current access information is stored in a locator table.
‡f - Electronic name
Subfield ‡f contains the electronic name of a file as it exists in the directory/subdirectory indicated in subfield ‡d on the host identified in subfield ‡a. Subfield ‡f may be repeated if a single logical file has been divided into parts and stored under different names. In this case, the separate parts should constitute a single bibliographic item. In all other cases, a file that may be retrieved under different filenames contains multiple occurrences of field 856, each with its corresponding electronic name in subfield ‡f. A filename may include wildcard characters (e.g., * or ?) if applicable. Use subfield ‡z to explain how files are named, if needed.
‡h - Processor of request
Subfield ‡h contains the username, or processor of the request; generally the data which precedes the at sign (@) in the host address.
‡i - Instruction
Subfield ‡i contains an instruction or command needed for the remote host to process a request.
‡j - Bits per second
Subfield ‡j contains the lowest and highest number of bits (binary units) of data that can be transmitted per second when connected to a host. The syntax for recording the number of bits per second (BPS) should be: <Lowest BPS>-<Highest BPS>. If only lowest given: <Lowest BPS>- ; If only highest given: -<Highest BPS>.
‡k - Password
Subfield ‡k contains the password required to access the electronic resource. An FTP site may require the user to enter an Internet Protocol address or may require a specific password. Electronically accessed catalogs may also require a password. If a system that requires a password will accept anything entered as valid, this subfield can be omitted from field 856. This subfield is used to record general-use passwords, and should not contain passwords requiring security. Textual instructions about passwords are contained in subfield ‡z (Public note).
‡l - Logon
Subfield ‡l contains characters needed to connect (i.e, logon, login, etc.) to an electronic resource or FTP site. (For many general-use File Transfer Protocol servers, access is gained by entering the string "anonymous.") An account number required for login may also be indicated. This subfield is used to record general-use logon strings which do not require special security. Do not use for security passwords.
‡m - Contact for access assistance
Subfield ‡m contains the name of a contact for assistance in accessing a resource at the host specified in subfield ‡a. For addresses relating to the content of the resource itself (i.e. the item represented by the title recorded in field 245 of the related bibliographic record) rather than access assistance, field 270 is used in the bibliographic record.
‡n - Name of location of host
Subfield ‡n contains the conventional name of the location of the host in subfield ‡a, including its physical (geographic) location.
‡o - Operating system
For informational purposes, the operating system used by the host specified in subfield ‡a may be indicated here. Conventions for the path and filenames may be dependent on the operating system of the host. For the operating system of the resource itself (i.e., the item represented by the title recorded in field 245 of the related bibliographic record), rather than the operating system of the host making it available, field 753 (Technical Details Access to Computer Files), subfield ‡c (Operating system) is used in the bibliographic record.
‡p - Port
Subfield ‡p contains the portion of the address that identifies a process or service in the host.
‡q - Electronic format type
Subfield ‡q contains an identification of the electronic format type, which is the data representation of the resource, such as text/html, ASCII, Postscript file, executable application, or JPEG image. The intent of specifying this element is to provide information necessary to allow people or machines to make decisions about the usability of the encoded data (what hardware and software might be required to display or execute it, for example). The electronic format type also determines the file transfer mode, or how data are transferred through a network. (Usually, a text file can be transferred as character data which generally restricts the text to characters in the ASCII ( American National Standard Code for Information Interchange(ANSI X3.4)) character set (i.e., the basic Latin alphabet, digits 0-9, a few special characters, and most punctuation marks) and text files with characters outside of the ASCII set, or non-textual data (e.g., computer programs, image data) must be transferred using another binary mode.) Electronic format type may be taken from enumerated lists such as registered Internet Media Types (MIME types).
‡r - Settings
Subfield ‡r contains the settings used for transferring data. Included in settings are: 1) Number Data Bits (the number of bits per character); 2) Number Stop Bits (the number of bits to signal the end of a byte); and 3) Parity (the parity checking technique used). The syntax of these elements is:
<Parity>-<Number Data Bits>-<Number Stop Bits>
If only the parity is given, the other elements of settings and their related hyphens are omitted (i.e., <Parity>). If one of the other two elements is given, the hyphen for the missing element is recorded in its proper position (i.e., <Parity>--<Number Stop Bits> or <Parity>-<Number Data Bits>- ). The values for parity are: O (Odd), E (Even), N (None), S (Space), and M (Mark).
‡s - File size
Subfield ‡s contains the size of the file as stored under the filename indicated in subfield ‡f. It is generally expressed in terms of 8-bit bytes (octets). It may be repeated in cases where the filename is repeated and directly follows the subfield ‡f to which it applies. This information is not given for journals, since field 856 relates to the entire title, not to particular issues.
‡t - Terminal emulation
Subfield ‡t contains an indication of a terminal emulation supported. Terminal emulation is usually specified for remote login (first indicator contains value 2 (Remote login (Telnet)).
‡u - Uniform Resource Identifier
Subfield ‡u contains the Uniform Resource Identifier (URI), which provides electronic access data in a standard syntax. This data can be used for automated access to an electronic item using one of the Internet protocols or by resolution of a URN. Field 856 is structured to allow for the creation of a URL from the concatenation of other separate field 856 subfields. Subfield ‡u may be used instead of those separate subfields or in addition to them. Subfield ‡u may be repeated only if both a URN and a URL or more than one URN are recorded. Field 856 is repeated if more than one URL needs to be recorded.
Substituting hexadecimal notation for diacritics and special characters in Uniform Resource Identifiers. When recording a URI in subfield ‡u, you may enter most of the spacing characters listed below as either characters or their hexadecimal equivalents. Consult the table below.
Do not confuse the spacing characters listed below with their long-valid non-spacing counterparts. Use of the spacing characters will be limited almost exclusively to URLs.
|Entry method||name||character||alternative entry (hex value)|
|Enter as character or hex value||Spacing circumflex/circumflex accent||^||%5E|
|Spacing underscore/low line1||_||%5F|
|Spacing grave/grave accent||`||%60|
|Enter as hex value only||Vertical bar||n/a||%7C|
1Because the Spacing Underscore may cause problems with MARC output, users may prefer to continue entering it with the hexadecimal value %5F.
‡v - Hours access method available
Subfield ‡v contains the hours that access to an electronic resource is available at the location indicated in this field. If the record is for a system or service, the hours of availability are recorded in field 307 (Hours, etc.). This subfield is only used to record hours of availability of the specific location indicated in field 856.
‡w - Record control number
Subfield ‡w contains the system control number of the related record preceded by the MARC code, enclosed in parentheses, for the agency to which the control number applies. The data in the subfield links field 856 to the MARC record having the same data in a control number field. See MARC Code List for Organizations , which also includes links to Canadian, United Kingdom, and German MARC Organization Code lists.
‡x - Nonpublic note
Subfield ‡x contains a note relating to the electronic location of the source identified in the field. The note is written in a form that is not adequate or intended for public display. It may also contain processing information about the file at the location specified.
‡y - Link text
This subfield contains link text that is used for display in place of the URL in subfield ‡u. When subfield ‡y is present, applications should use the contents of subfield ‡y as the link, instead of the content of subfield ‡u when linking to the destination in subfield ‡u. Subfield ‡u is independent of the 2nd indicator value.
‡z - Public note
Subfield ‡z contains a note relating to the electronic location of the source identified in the field. The note is written in a form that is adequate or intended for public display.
‡2 - Access method
The code defined for use with 1st indicator value 7. Use subfield ‡2 to record access methods other than the four main TCP/IP protocols specified in the 1st indicator. The data in this subfield corresponds with the access schemes specified in Uniform Resource Locators (URL), a product of the Uniform Resource Identifiers Working Group of the IETF. The Internet Assigned Numbers Authority (IANA) maintains a registry of URL schemes and defines the syntax and use of new schemes. Code from the Electronic Access Methods Code List which is maintained by the Library of Congress.
‡3 - Materials specified
Subfield ‡3 contains information that specifies the part of the bibliographic item to which the field applies.
856 4 2 ‡3 Finding aid ‡u http://lcweb2.loc.gov/ammem/ead/jackson.sgm
‡8 - Field link and sequence number
Subfield ‡8 contains data that identifies linked fields and may also propose a sequence for the linked fields. Subfield ‡8 may be repeated to link a field to more than one other group of fields.
The structure and syntax for the field link and sequence number subfield is: ‡8<linking number>.<sequence number>
The linking number is the first data element in the subfield and required if the subfield is used. It is a variable-length whole number that occurs in subfield ‡8 in all fields that are to be linked. Fields with the same linking number are considered linked. A linking number of "0" (zero) is not used in this field.
The sequence number is separated from the linking number by a period "." and may be optional. It is a variable-length whole number that may be used to indicate the relative order for display of the linked fields (lower sequence numbers displaying before higher ones).
Subfield ‡8 is always the first subfield in the field when it is used.