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
36757 7.64% 18443029530 49.84%
2 435650 90.53% 10087282360 27.26%
3 h2
h2-16
h2-15
h2-14
spdy/3.1
spdy/3
http/1.1
257 0.05% 5119083184 13.83%
4 http/1.1
4089 0.85% 2169531808 5.86%
5 spdy/3.1
spdy/3
http/1.1
109 0.02% 580363667 1.57%
6 h2
h2-fb
http/1.1
31 0.01% 333916178 0.90%
7 h2
spdy/3.1
http/1.1
724 0.15% 102151039 0.28%
8 h2
258 0.05% 62296488 0.17%
9 grpc-exp
h2
66 0.01% 55041554 0.15%
10 spdy/3
http/1.1
363 0.08% 10791720 0.03%
11 apns-security-v3
apns-pack-v1
7 0.00% 9221440 0.02%
12 http/1.1
spdy/3.1
h2-14
h2
109 0.02% 4853001 0.01%
13 h2
h2-fb
10 0.00% 4349255 0.01%
14 h2
h2-16
h2-15
h2-14
http/1.1
21 0.00% 3463782 0.01%
15 h2-16
h2-15
h2-14
h2
spdy/3.1
http/1.1
93 0.02% 3200312 0.01%
16 http/1.1
spdy/3.1
h2
90 0.02% 2292212 0.01%
17 http/1.1
http/1.0
46 0.01% 2240041 0.01%
18 http/1.1
spdy/3.1
142 0.03% 1602481 0.00%
19 h2
spdy/3.1
ahfs/1.0
http/1.1
4 0.00% 1329427 0.00%
20 spdy/3
spdy/3.1
http/1.1
130 0.03% 1232936 0.00%

Selected ALPNs (Server Hello)

Rank ALPN Fingerprints % Fingerprints Connections % Connections
1 550358 76.26% 17716068058 66.68%
2 h2 73968 10.25% 4810368319 18.10%
3 http/1.1 96087 13.31% 3995209546 15.04%
4 grpc-exp 111 0.02% 37015595 0.14%
5 apns-pack-v1:4096:4096 10 0.00% 7895192 0.03%
6 spdy/3.1 986 0.14% 3587370 0.01%
7 http/1.1 4 0.00% 236990 0.00%
8 h2-fb 7 0.00% 15481 0.00%
9 bep-relay 15 0.00% 13021 0.00%
10 http/1.0 15 0.00% 1722 0.00%
11 fbvp 12 0.00% 1207 0.00%
12 rtmp 5 0.00% 1164 0.00%
13 h2-14 70 0.01% 1070 0.00%
14 h2 2 0.00% 1022 0.00%
15 x-amzn-mqtt-ca 4 0.00% 700 0.00%
16 spdy/3 26 0.00% 282 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 43908 9.12% 26786551169 72.38%
2 h2 38903 8.08% 24137965039 65.23%
3 spdy/3.1 2412 0.50% 5821860861 15.73%
4 spdy/3 1235 0.26% 5713969353 15.44%
5 h2-14 774 0.16% 5133585983 13.87%
6 h2-16 553 0.11% 5126059945 13.85%
7 h2-15 512 0.11% 5125928362 13.85%
8 h2-fb 164 0.03% 338719965 0.92%
9 grpc-exp 101 0.02% 55047871 0.15%
10 apns-security-v3 8 0.00% 9384723 0.03%
11 apns-pack-v1 8 0.00% 9333380 0.03%
12 http/1.0 74 0.02% 2247664 0.01%
13 ahfs/1.0 10 0.00% 2135005 0.01%
14 apns-security-v2 3 0.00% 659428 0.00%
15 spdy/2 262 0.05% 423169 0.00%
16 x-amzn-mqtt-ca 9 0.00% 102091 0.00%
17 quic 36 0.01% 56017 0.00%
18 spdy/1 160 0.03% 40686 0.00%
19 HTTP-draft-09/2.0 4 0.00% 35479 0.00%
20 spdy/3.1-fb-0.5 5 0.00% 34912 0.00%