BIP141: Block cost clrification

Author: jl2012

bip-0141.mediawiki

@@ -108,9 +108,13 @@ If the version byte is 1 to 16, no further interpretation of the witness program
 
 Blocks are currently limited to 1,000,000 bytes (1MB) total size. We change this restriction as follows:
 
-''Block cost'' is defined. The cost of each byte in the existing header and transactions is 4, while the cost of each byte in witness data is 1.
+''Block cost'' is defined as ''Base size'' * 3 + ''Total size''.
 
-The new rule is total ''block cost'' ≤ 4,000,000.
+''Base size'' is the block size in bytes with the original transaction serialization without any witness-related data, as seen by a non-upgraded node.
+
+''Total size'' is the block size in bytes with transactions serialized as described in [[bip-0144.mediawiki|BIP144]], including base data and witness data.
+
+The new rule is ''block cost'' ≤ 4,000,000.
 
 ==== Sigops ====