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Re: Annex 48A Jitter Test Patterns

> This has come up before in logic track discussions, but the way I read the
> max packet length, there is nothing in the standard for 10gig that says a
> longer packet is 'not' legal.  And there is no mechanism I am aware of that
> prevents a longer packet from coming through to the mac.


You should go back and review Clause 4, which specifies the Ethernet MAC (for
all speeds). It is very explicit that the only value allowed in Ethernet for
maxFrameSize is 1518 bytes, and if VLAN tagging is used this value is allowed
to increase to 1522. That's it.
A standards compliant 802.3/Ethernet MAC MUST truncate a frame that exceeds
the maxFrameSize parameter, and and report a frame_too_long error.
The 802.3ae Task Force unanimously adopted the objectives to "Preserve the min
and max frame size" and to "Preserve the Ethernet frame format". Threfore, at
this time, 10-Gigabit Ethernet must comply with these requirements.