A
linkback is a method for
Web authors to obtain notifications when other authors
link to one of their documents. This enables authors to keep track of who is linking to, or referring to, their articles. The three methods (
Refback,
Trackback, and
Pingback) differ in how they accomplish this task.
Any of the four terms -- Linkback, Trackback, Pingback, or (rarely) Refback -- might also refer colloquially to items within a section upon the linked page that display the received notifications, usually along with a reciprocal link; Trackback is used most often for this purpose. Also, the word Trackback is often used colloquially to mean any kind of Linkback.
Linkback is also the name of an OLE-like open source framework for Mac OS X.
{| class="wikitable"
|-
!
! Refback
! Trackback
! Pingback
|-
| Trigger mechanism
| Visitor to linking site clicks on the link, and his browser takes him to the linked site
| Code on linking server examines added or updated documents, extracts links, and sends notification to linked server for each link found
| Code on linking server examines added or updated documents, extracts links, and sends notification to linked server for each link found
|-
| Notification medium
| HTTP referrer value
| HTTP POST
| XML-RPC call
|-
| Capture mechanism
| Examination of incoming HTTP referrer values
| Trackback capture script
| XML-RPC function
|-
| Information sent by linking server
| None
|
Linking site name (Optional)
Linking post title (Optional)
Linking post excerpt (Optional)
Linking post URL
|
Linked post URL
Linking post URL
|-
| Additional information presented to linked server
|
HTTP referrer sent by a visitor's browser upon clicking the link
| IP address of linking server
| IP address of linking server
|-
| Autodiscovery mechanism (how the linking server finds out how and where to send the notification)
| None
| Specially-formatted information within the body of the linked page
| Special HTTP header or LINK tag on the linked page
|-
| Action required when notification is received
|
Extract referrer value from incoming HTTP headers
Retrieve referring page
Parse retrieved page for desired information
|
Gather desired information from
* Given parameters
* or retrieving and parsing the given URL
|
Retrieve page at "linking post URL"
Parse retrieved page for desired information
|-
| Advantages
| Requires no special code on linking server (the link itself becomes the notification when someone clicks on it)
| All the information desired by the linked server (Linking site name, post title, excerpt) is present in the notification itself
|
Notification mechanism has a complete technical specification
Less susceptible to spamming
|-
| Disadvantages
|
No notification unless someone actually clicks on the link
Relies upon visitors' browsers sending proper HTTP referrer information
Linked site must retrieve and parse linking site's page to extract the information it wants
|
Notification requires positive action by linking server
Notification mechanism has only a partial technical specification
Autodiscovery information may prevent XHTML validation
|
Notification requires positive action by linking server
Linked site must retrieve and parse linking site's page to extract the information it wants
|}
See also
Backlink
Search engine optimization
External links
Pingback specification
TrackBack specification
Find Backlink Help
TrackBack Working Group
WordPress Tutorial: Using TrackBack and Pingback
Trackback Validator Plugin for WordPress: TrackBack spam blocker
TrackBack in blogger
Multiple Blog Services Pinger
TrackBackr JS TrackBack system with integrated spam blocker
Category:Blogs
