1  # The "les" ENR entry
 2  
 3  This specification defines the "les" ENR entry, which provides information about the [les
 4  capability] provided by a node. The presence of this entry in a node's ENR indicates that
 5  the node is acting as a light client server. ENRs containing the "les" entry must also
 6  contain an [eth entry], which provides information about the specific Ethereum blockchain
 7  served by LES.
 8  
 9  ## Entry Format
10  
11      entry-key   = "les"
12      entry-value = [ vflux-version ]
13  
14  At this time, the "les" entry is a single element list containing the version number of
15  the 'vflux' payment protocol.
16  
17  In order to be compatible with future versions of this specifications, implementations
18  should ignore any additional list elements in `entry-value`.
19  
20  ## Change Log
21  
22  ### vflux-version (March 2021)
23  
24  In March 2021, the les entry was updated to include the vflux version number.
25  
26  ### Initial Version (October 2019)
27  
28  The initial version of the les entry was an empty list with the sole purpose of
29  signaling LES server support.
30  
31  [les capability]: ../caps/les.md
32  [eth entry]: ./eth.md