RFC 791, "Internet Protocol", September 1981

Note: This RFC has been updated by RFC 1349, RFC 2474, RFC 6864

Errata ID: 4752
Status: Held for Document Update
Type: Technical
Publication Format(s) : TEXT
Reported By: Markus Klemm
Date Reported: 2016-07-29
Held for Document Update by: Terry Manderson
Date Held: 2017-03-01

Section 3.1. says:

The Option Length is the number of octets 
in the option counting the type, length, 
pointer, and overflow/flag octets (maximum length 40).

It should say:

The Option Length is the number of octets 
in the option counting the type, length, 
pointer, overflow/flag octets 
and timestamp area (maximum length 40).

Notes:

The original version implies that the length is only the sum of the constant fields, in this case, 4. This is in conflict with
A) All prior statements that the length is variable
B) The pointer with it >=5 constraint, implies the timestamp area is always full, which is the case when pointer > length
C) Any need to know how much timestamps will follow

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