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256 ELECTRONIC LOCATION AND ACCESS
Field Definition
This field contains the information required to locate the electronic item described by the
bibliographic record. 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 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 item.
Occurrence
Optional. Repeatable when the location data elements vary (subfields $a, $b, $d) and when more than
one access method may be used. It is also repeatable whenever the electronic filename varies
(subfield $f), except when a single intellectual item is divided into different parts for online storage or
retrieval.
Indicators
Indicator 1: Access Method
# No information provided
0 Email
1 FTP
2 Remote login (Telnet)
3 Dial-up
4 HTTP
7 Method specified in subfield $y
Indicator 2: Blank (not defined)
Subfields
$a
Host name
Repeatable.
$b Access number
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. A telephone number is recorded as follows: [country code]-[area code]-[telephone
number]. Example: 49-69-15251140 (a number in Frankfurt, Germany); 1-202-7076237 (a
number in the U.S., Washington, D.C.). If an extension is applicable, include it after the
telephone number preceded by ‘x’. Example: 1-703-3589800x515 (telephone number with
extension). Repeatable.
$c
Compression information
Repeatable.
$d Path
Repeatable.
$e Date and Hour of Consultation and Access
The time, in the form YYYYMMDDHHMM, at which the electronic item was last accessed.
Not repeatable.
$f Electronic name
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 256, each with its corresponding
electronic name in subfield $f. A filename may include wildcard characters (e.g., ‘*’ or ‘?’) if
applicable, with a note in subfield $z explaining how files are named. NOTE: Filenames may be
case-sensitive for some systems. This subfield may also contain the name of the electronic
publication or conference. Repeatable.
$h Processor of request
The username, or processor of the request; generally the data which precedes the at sign ( ‘@’) in
the host address. Not repeatable.
$i Instruction
An instruction or command needed for the remote host to process a request. Repeatable.
$j Bits per second
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]. Not repeatable.
$k Password
Used to record general-use passwords, and should not contain passwords requiring security. Not
repeatable.
$l
Logon/login
General-use logon/login strings which do not require special security. Not repeatable.
$m Contact for access assistance
Repeatable.
$n Name of location of host in subfield $a.
Not repeatable.
$o Operating system
For information, the operating system used by the host specified in subfield $a is indicated in this
subfield. Not repeatable.
$p Port
The portion of the address that identifies a process or service in the host. Not repeatable.
$q Electronic Format Type
Contains an identification of the electronic format type, whic h determines 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) character set (i.e., the basic Latin alphabet, digits 0-9, a few special
characters, and most punctuation marks). Text files with characters outside of the ASCII set, or
non-textual data (e.g., computer programs, image data) must be transferred using another file
transfer mode, usually binary mode. Electronic format type may be taken from lists such as
registered Internet Media types (MIME types). Not repeatable.
$r Settings
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 of Data Bits]-[Number of 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 of Stop Bits] or [Parity]-[Number of Data Bits]-). The values for parity are: O
(Odd), E (Even), N (None), S (Space), and M (Mark). Not repeatable.
$s File size
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 256 relates to the entire title, not to particular issues. Repeatable.
$t Terminal emulation
Repeatable.
$u Uniform Resource Identifier
The URI, which provides standard syntax for locating an object using existing Internet protocols.
Field 256 is structured to allow for the creation of a URL from the concatenation of other
separate 256 subfields. Subfield $u may be used instead of those separate subfields or in addition
to them. The field is repeated if more than one URL needs to be recorded.
Not repeatable
$v Hours access method available
The hours that access to an electronic resource is available at the location indicated in this field.
Repeatable
$w Record control number
Repeatable.
$x Non-public note
Repeatable.
$y Access method
The access method when the first indicator position contains value 7 (Method specified in
subfield $y). This subfield may include access methods other than the main TCP/IP protocols
specified in the first indicator. The data in this subfield corresponds with the access schemes
specified in Uniform Resource Locators (URL) (RFC 1738), 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. Not
repeatable.
$z Public note
Repeatable.
$2 Link text
Used for display in place of the URL in subfield $u (Uniform Resource Identifier). When
subfield $2 is present, applications should use the contents of it as the link instead of subfield $u
linking to the destination in subfield $u. Repeatable.
Examples
EX 1
256 4#$uhttp://purl.pt/441
== Див. також ==
* [[UNIMARC для записів про зберігання]]