diff --git a/Hash2Pub/src/Hash2Pub/ASN1Coding.hs b/Hash2Pub/src/Hash2Pub/ASN1Coding.hs
index 7bafda5..c2524ed 100644
--- a/Hash2Pub/src/Hash2Pub/ASN1Coding.hs
+++ b/Hash2Pub/src/Hash2Pub/ASN1Coding.hs
@@ -28,6 +28,9 @@ import Debug.Trace
 -- Only some kinds of payloads can be split, and only to a limited number of parts.
 -- This function only deals with potentially large payload types and passes the
 -- rest as-is.
+--
+-- The common IPv6 path MTU is 1280 bytes. When substracting 40 bytes TCP header (minimum) and 8 bytes UDP header, that gives remaining 1232 bytes for the payload.
+-- Leaving room for IPv6 header extensions, 1200 bytes appear to be a good default.
 splitPayload :: Int                 -- number of parts to split payload into
              -> ActionPayload       -- payload to be split
              -> [ActionPayload]     -- list of smaller payloads