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
45143 7.85% 22409243536 52.00%
2 520499 90.45% 11403757401 26.46%
3 h2
h2-16
h2-15
h2-14
spdy/3.1
spdy/3
http/1.1
264 0.05% 5238637674 12.16%
4 http/1.1
4667 0.81% 2758008264 6.40%
5 spdy/3.1
spdy/3
http/1.1
111 0.02% 599888146 1.39%
6 h2
h2-fb
http/1.1
36 0.01% 358750505 0.83%
7 h2
spdy/3.1
http/1.1
734 0.13% 111743790 0.26%
8 grpc-exp
h2
68 0.01% 87214213 0.20%
9 h2
303 0.05% 67861962 0.16%
10 spdy/3
http/1.1
375 0.07% 11176938 0.03%
11 apns-security-v3
apns-pack-v1
13 0.00% 9771340 0.02%
12 http/1.1
spdy/3.1
h2-14
h2
109 0.02% 5206508 0.01%
13 h2
h2-fb
10 0.00% 4623596 0.01%
14 h2
h2-16
h2-15
h2-14
http/1.1
22 0.00% 3506756 0.01%
15 h2-16
h2-15
h2-14
h2
spdy/3.1
http/1.1
96 0.02% 3250214 0.01%
16 http/1.1
http/1.0
51 0.01% 2794906 0.01%
17 http/1.1
spdy/3.1
h2
92 0.02% 2388021 0.01%
18 http/1.1
spdy/3.1
146 0.03% 1754804 0.00%
19 h2
spdy/3.1
ahfs/1.0
http/1.1
4 0.00% 1389253 0.00%
20 http/1.1
spdy/3
spdy/3.1
60 0.01% 1274801 0.00%

Selected ALPNs (Server Hello)

Rank ALPN Fingerprints % Fingerprints Connections % Connections
1 621710 76.34% 21530013100 68.71%
2 h2 86609 10.64% 5265536839 16.80%
3 http/1.1 104719 12.86% 4475208996 14.28%
4 grpc-exp 113 0.01% 52399253 0.17%
5 apns-pack-v1:4096:4096 15 0.00% 8365035 0.03%
6 spdy/3.1 1005 0.12% 3599882 0.01%
7 http/1.1 4 0.00% 252524 0.00%
8 h2-fb 7 0.00% 15515 0.00%
9 bep-relay 15 0.00% 13292 0.00%
10 x-amzn-mqtt-ca 9 0.00% 4016 0.00%
11 http/1.0 15 0.00% 2151 0.00%
12 fbvp 12 0.00% 1514 0.00%
13 h2 2 0.00% 1242 0.00%
14 rtmp 5 0.00% 1164 0.00%
15 h2-14 71 0.01% 1101 0.00%
16 spdy/3 26 0.00% 290 0.00%
17 bep/1.0 8 0.00% 85 0.00%
18 ncp 4 0.00% 57 0.00%
19 h2-16 8 0.00% 24 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 53126 9.23% 31517149503 73.14%
2 h2 47546 8.26% 28297200284 65.67%
3 spdy/3.1 2564 0.45% 5971600162 13.86%
4 spdy/3 1402 0.24% 5853590269 13.58%
5 h2-14 799 0.14% 5253805410 12.19%
6 h2-16 577 0.10% 5245712263 12.17%
7 h2-15 536 0.09% 5245581120 12.17%
8 h2-fb 183 0.03% 363831865 0.84%
9 grpc-exp 106 0.02% 87221003 0.20%
10 apns-security-v3 14 0.00% 9966799 0.02%
11 apns-pack-v1 14 0.00% 9884896 0.02%
12 http/1.0 116 0.02% 2824889 0.01%
13 ahfs/1.0 10 0.00% 2231581 0.01%
14 apns-security-v2 3 0.00% 706198 0.00%
15 spdy/2 405 0.07% 453877 0.00%
16 x-amzn-mqtt-ca 12 0.00% 117224 0.00%
17 spdy/1 299 0.05% 64110 0.00%
18 quic 37 0.01% 59363 0.00%
19 h2c 65 0.01% 54904 0.00%
20 HTTP-draft-09/2.0 5 0.00% 39143 0.00%