On: My £4 a month server can handle 4.2M requests a da...

[blibble]

there's still ascii FIX floating around on the market data side for a few esoteric venues

FAST is not particularly common in Europe

the large European venues use fixed-width binary encoding (LSE group, Euronext, CBOE Europe)

[blacklion → blibble]

Eurex uses FAST for sure, but I can be wrong about "common".

[gpderetta → blacklion]

Eurex/XETRA EOBI no longer uses FAST. It is about 8 year old t this point, but IIRC some products are still on the older protocol.

[nly → blibble]

Euronext uses SBE specifically.