Microchip ENC424J600 25MHz Crystal Tolerance

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ENC424J600 requires ±50ppm max for 25MHz crystal @ -40ºC to 85ºC.
I am designing with 25MHz crystal @ Initial Tol=±30ppm, Temp Stability=±40ppm, Aging=±5ppm/year max

Can someone please advise if my selection is feasible ?
Is the ±50ppm include both initial tolerance and temp stability ?
Also IEEE802.3 requires 25MHz clock with tolerance ±100ppm instead of ±50ppm.
If we drive >±50ppm but <±100ppm, what will happen to the ethernet operation ?
 

Errors of 50 or 100ppm only affect the calculation of packet response times and distance limits of cable for ethernet communication, I believe.

Often products for ethernet are not exposed to -40~85'C so the S curved +/-50 ppm can be reduced by environmental choice.

If this was being used in a harsh environment then a 3ppm TCXO clock for $2 would be my choice.
https://www.digikey.com/product-detail/en/FOX924B-25.000/631-1074-2-ND/1024666


Good crystals only age 1ppm /yr 5ppm/yr implies poor quality on a microslice cheap crystal.
 

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