MARC 21 Concise Format for Classification Data: 856: Electronic Location and Access (Network Development and MARC Standards Office, Library of Congress)

Information required to locate an electronic item. The information identifies the electronic location containing the item or from which it is available. It also contains information to retrieve the item by the access method identified in the first indicator position. 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 a library catalog.

In MARC 21 classification records, this field may be used to link an electronic resource intended to supplement the classification scheme, such as an image of a map in a table related to the classification of geographic names.

Field 856 is repeated when the location elements vary (the URL in subfields $a, $b, $c when used). It is also repeated when more than one access method is used, mirror sites are recorded, different formats/resolutions with different URLs are indicated, and related items are recorded.

First - Access method

# - No information provided

0 - Email

1 - FTP

2 - Remote login (Telnet)

3 - Dial-up

4 - HTTP

7 - Method specified in subfield $2

Second - Relationship

# - No information provided

0 - Resource

1 - Version of resource

2 - Related resource

8 - No display constant generated

$a - Host name (R)

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 (R)

Access number associated with a host. Can be an Internet Protocol (IP) numeric address , or a telephone number if dial-up access is provided through a telephone line. This data changes frequently and may be generated by the system, rather than statically stored.

$c - Compression information (R)

Information about the compression of a file, in particular, whether a specific program is required to decompress the file.

$f - Electronic name (R)

$h - Processor of request (NR)

Username, or processor of the request; generally the data which precedes the at sign (@) in the host address.

$i - Instruction (R)

Instruction or command needed for the remote host to process a request.

$j - Bits per second (NR)

$l - Logon (NR)

Characters needed to connect (i.e., logon, login, etc.) to an electronic resource or FTP site. Used to record general-use logon strings which do not require special security.

$m - Contact for access assistance (R)

$n - Name of location of host (NR)

Conventional name of the location of the host in subfield $a, including its physical (geographic) location.

$o - Operating system (NR)

$p - Port (NR)

Portion of the address that identifies a process or service in the host.

$q - Electronic format type (NR)

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. Electronic format type may be taken from enumerated lists such as registered Internet Media Types (MIME types).

$t - Terminal emulation (R)

$u - Uniform Resource Identifier (R)

Uniform Resource Identifier (URI), which provides standard syntax for locating an object using existing Internet protocols. Field 856 is structured to allow for the creation of a URL from the concatenation of other separate 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 or a URL or more than one URN are recorded.

$v - Hours access method available (R)

$w - Record control number (R)

$x - Nonpublic note (R)

$y - Link text (R)

Used for display in place of the URL in subfield $u (Uniform resource identifier). When subfield $y is present, applications should use the contents of it as the link instead of subfield $u linking to the destination in subfield $u.

$z - Public note (R)

$2 - Access method (NR)

Access method when the first indicator value contains value 7 (Method specified in subfield $2). Code from: Electronic Access Methods Code List.

$3 - Materials specified (NR)

$6 - Linkage (NR)

See the description of this subfield in Appendix A: Control Subfields.

$8 - Field link and sequence number (NR)

See the description of this subfield in Appendix A: Control Subfields.


856	7#$uhttp://minaret.loc.gov/images/gschedule/G1350a.gif$yMap of West south central states

856 - Electronic Location and Access (R)