Application Layer Protocol Negotiation (ALPN)

ALPN provides a way for client's to specify the application protocols they support.

Top Client ALPNs

Rank ALPN Unique Fingerprints % Fingerprints Connections % Connections
1 h2
http/1.1
35371 8.67% 15942275803 48.51%
2 364495 89.33% 8896618706 27.07%
3 h2
h2-16
h2-15
h2-14
spdy/3.1
spdy/3
http/1.1
249 0.06% 5033057898 15.31%
4 http/1.1
3630 0.89% 1873201732 5.70%
5 spdy/3.1
spdy/3
http/1.1
108 0.03% 563720838 1.72%
6 h2
h2-fb
http/1.1
31 0.01% 328718454 1.00%
7 h2
spdy/3.1
http/1.1
709 0.17% 92192865 0.28%
8 grpc-exp
h2
65 0.02% 45075703 0.14%
9 h2
235 0.06% 40163197 0.12%
10 spdy/3
http/1.1
344 0.08% 9707736 0.03%
11 apns-security-v3
apns-pack-v1
4 0.00% 9022427 0.03%
12 http/1.1
spdy/3.1
h2-14
h2
108 0.03% 4278581 0.01%
13 h2
h2-fb
10 0.00% 4226603 0.01%
14 h2
h2-16
h2-15
h2-14
http/1.1
21 0.01% 3429570 0.01%
15 h2-16
h2-15
h2-14
h2
spdy/3.1
http/1.1
92 0.02% 3142332 0.01%
16 http/1.1
spdy/3.1
h2
89 0.02% 2206041 0.01%
17 http/1.1
http/1.0
44 0.01% 1439093 0.00%
18 http/1.1
spdy/3.1
139 0.03% 1367018 0.00%
19 h2
spdy/3.1
ahfs/1.0
http/1.1
4 0.00% 1280104 0.00%
20 spdy/3
spdy/3.1
http/1.1
127 0.03% 1123888 0.00%

Selected ALPNs (Server Hello)

Rank ALPN Fingerprints % Fingerprints Connections % Connections
1 486002 75.28% 14706177393 63.92%
2 h2 69373 10.75% 4526867520 19.68%
3 http/1.1 88941 13.78% 3733771882 16.23%
4 grpc-exp 109 0.02% 27265200 0.12%
5 apns-pack-v1:4096:4096 7 0.00% 7696627 0.03%
6 spdy/3.1 979 0.15% 3551529 0.02%
7 http/1.1 4 0.00% 223597 0.00%
8 h2-fb 7 0.00% 15481 0.00%
9 bep-relay 12 0.00% 12472 0.00%
10 http/1.0 14 0.00% 1241 0.00%
11 fbvp 12 0.00% 1162 0.00%
12 rtmp 5 0.00% 1131 0.00%
13 h2-14 67 0.01% 1005 0.00%
14 h2 2 0.00% 824 0.00%
15 spdy/3 24 0.00% 270 0.00%
16 x-amzn-mqtt-ca 4 0.00% 119 0.00%
17 bep/1.0 8 0.00% 85 0.00%
18 h2-16 8 0.00% 24 0.00%
19 ncp 1 0.00% 2 0.00%
20 http/1.1\x00 1 0.00% 1 0.00%

Popular ALPNs supported by clients

Rank ALPN Fingerprints % Fingerprints Connections % Connections
1 http/1.1 41945 10.28% 23867794814 72.63%
2 h2 37406 9.17% 21502695554 65.43%
3 spdy/3.1 2341 0.57% 5707455846 17.37%
4 spdy/3 1166 0.29% 5609862355 17.07%
5 h2-14 736 0.18% 5046472246 15.36%
6 h2-16 523 0.13% 5039936902 15.34%
7 h2-15 476 0.12% 5039802648 15.34%
8 h2-fb 144 0.04% 333395865 1.01%
9 grpc-exp 88 0.02% 45080695 0.14%
10 apns-security-v3 5 0.00% 9173579 0.03%
11 apns-pack-v1 5 0.00% 9134097 0.03%
12 ahfs/1.0 10 0.00% 2060346 0.01%
13 http/1.0 59 0.01% 1445161 0.00%
14 apns-security-v2 3 0.00% 620862 0.00%
15 spdy/2 226 0.06% 381737 0.00%
16 x-amzn-mqtt-ca 9 0.00% 68287 0.00%
17 quic 32 0.01% 51176 0.00%
18 spdy/1 128 0.03% 36736 0.00%
19 spdy/3.1-fb-0.5 5 0.00% 34903 0.00%
20 HTTP-draft-09/2.0 3 0.00% 34710 0.00%