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
173310 0.27% 33897014229 100.66%
2 http/1.1
144636 0.22% 6968811044 20.69%
3 428310 0.66% 6778517860 20.13%
4 h2
h2-fb
http/1.1
38 0.00% 208133605 0.62%
5 grpc-exp
h2
59 0.00% 197456537 0.59%
6 h2
1398 0.00% 158842927 0.47%
7 h2
h2-16
h2-15
h2-14
spdy/3.1
spdy/3
http/1.1
158 0.00% 100734752 0.30%
8 spdy/3.1
spdy/3
http/1.1
60 0.00% 16180228 0.05%
9 h2
spdy/3.1
http/1.1
267 0.00% 9815343 0.03%
10 http/1.1
h2
11534 0.02% 6902633 0.02%
11 apns-security-v3
apns-pack-v1
18 0.00% 4150081 0.01%
12 http/1.1
https/1.1
8 0.00% 3642529 0.01%
13 http/0.9
http/1.0
http/1.1
spdy/1
spdy/2
spdy/3
h2
h2c
hq
28 0.00% 3089092 0.01%
14 http/1.1
http/1.0
47 0.00% 1724044 0.01%
15 hq
h2c
h2
spdy/3
spdy/2
spdy/1
http/1.1
http/1.0
http/0.9
16 0.00% 1595856 0.00%
16 h2
http/1.1
http/1.0
33 0.00% 1500889 0.00%
17 h2
h2-fb
5 0.00% 1137197 0.00%
18 hq
h2c
spdy/3
spdy/2
spdy/1
http/1.0
http/0.9
6 0.00% 617421 0.00%
19 http/0.9
http/1.0
spdy/1
spdy/2
spdy/3
h2c
hq
6 0.00% 615776 0.00%
20 x-amzn-mqtt-ca
40 0.00% 362742 0.00%

Selected ALPNs (Server Hello)

Rank ALPN Fingerprints % Fingerprints Connections % Connections
1 5419081 78.83% 8783252108 82.15%
2 h2 783353 11.39% 981480119 9.18%
3 http/1.1 655864 9.54% 923076053 8.63%
4 grpc-exp 26 0.00% 954140 0.01%
5 apns-pack-v1:4096:4096 5 0.00% 90045 0.00%
6 x-amzn-mqtt-ca 23 0.00% 60686 0.00%
7 x-amzn-http-ca 7 0.00% 6578 0.00%
8 http/1.1 4 0.00% 5832 0.00%
9 bep-relay 3 0.00% 1626 0.00%
10 ncp 2 0.00% 1503 0.00%
11 mqtt 2 0.00% 531 0.00%
12 h2 1 0.00% 260 0.00%
13 fbvp 4 0.00% 260 0.00%
14 h2-14 3 0.00% 167 0.00%
15 http/1.0 3 0.00% 124 0.00%
16 spdy/3.1 1 0.00% 9 0.00%

Popular ALPNs supported by clients

Rank ALPN Fingerprints % Fingerprints Connections % Connections
1 http/1.1 331200 0.51% 41221102044 122.41%
2 h2 187539 0.29% 34587710956 102.71%
3 h2-fb 126 0.00% 209275587 0.62%
4 grpc-exp 102 0.00% 197473502 0.59%
5 spdy/3.1 1196 0.00% 127570216 0.38%
6 spdy/3 803 0.00% 123271158 0.37%
7 h2-14 405 0.00% 101037826 0.30%
8 h2-16 293 0.00% 100812767 0.30%
9 h2-15 289 0.00% 100810379 0.30%
10 http/1.0 191 0.00% 9416428 0.03%
11 spdy/2 500 0.00% 6441961 0.02%
12 h2c 123 0.00% 6282147 0.02%
13 spdy/1 378 0.00% 6200657 0.02%
14 http/0.9 103 0.00% 6186470 0.02%
15 hq 72 0.00% 6173223 0.02%
16 apns-security-v3 19 0.00% 4161480 0.01%
17 apns-pack-v1 19 0.00% 4151290 0.01%
18 https/1.1 8 0.00% 3642529 0.01%
19 quic 37 0.00% 421684 0.00%
20 x-amzn-mqtt-ca 42 0.00% 362816 0.00%