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
78341 9.30% 29931615631 55.09%
2 752853 89.36% 13699739084 25.21%
3 h2
h2-16
h2-15
h2-14
spdy/3.1
spdy/3
http/1.1
271 0.03% 5377073421 9.90%
4 http/1.1
5521 0.66% 3920428252 7.22%
5 spdy/3.1
spdy/3
http/1.1
134 0.02% 622559875 1.15%
6 h2
h2-fb
http/1.1
36 0.00% 387741478 0.71%
7 h2
spdy/3.1
http/1.1
746 0.09% 127112752 0.23%
8 grpc-exp
h2
73 0.01% 118448644 0.22%
9 h2
364 0.04% 86350001 0.16%
10 spdy/3
http/1.1
394 0.05% 11599478 0.02%
11 apns-security-v3
apns-pack-v1
15 0.00% 10338741 0.02%
12 http/1.1
spdy/3.1
h2-14
h2
111 0.01% 5608275 0.01%
13 h2
h2-fb
10 0.00% 4989972 0.01%
14 http/1.1
http/1.0
56 0.01% 3714507 0.01%
15 h2
h2-16
h2-15
h2-14
http/1.1
23 0.00% 3542226 0.01%
16 h2-16
h2-15
h2-14
h2
spdy/3.1
http/1.1
99 0.01% 3370574 0.01%
17 http/1.1
spdy/3.1
h2
94 0.01% 2460682 0.00%
18 http/1.1
spdy/3.1
147 0.02% 1989547 0.00%
19 http/1.1
h2
190 0.02% 1678767 0.00%
20 h2
spdy/3.1
ahfs/1.0
http/1.1
4 0.00% 1552170 0.00%

Selected ALPNs (Server Hello)

Rank ALPN Fingerprints % Fingerprints Connections % Connections
1 794124 76.86% 28812825014 71.79%
2 h2 120110 11.63% 5970479651 14.88%
3 http/1.1 117575 11.38% 5283168647 13.16%
4 grpc-exp 116 0.01% 54872062 0.14%
5 apns-pack-v1:4096:4096 15 0.00% 8577011 0.02%
6 spdy/3.1 1014 0.10% 3607413 0.01%
7 http/1.1 5 0.00% 297486 0.00%
8 x-amzn-mqtt-ca 14 0.00% 30216 0.00%
9 h2-fb 7 0.00% 15515 0.00%
10 bep-relay 15 0.00% 14032 0.00%
11 h2 2 0.00% 3131 0.00%
12 http/1.0 16 0.00% 2343 0.00%
13 fbvp 12 0.00% 1910 0.00%
14 rtmp 5 0.00% 1164 0.00%
15 h2-14 72 0.01% 1120 0.00%
16 spdy/3 26 0.00% 290 0.00%
17 ncp 5 0.00% 94 0.00%
18 bep/1.0 8 0.00% 85 0.00%
19 x-amzn-http-ca 1 0.00% 33 0.00%
20 dot 1 0.00% 25 0.00%
21 h2-16 8 0.00% 24 0.00%
22 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 87573 10.39% 40412567547 74.38%
2 h2 81174 9.64% 36055549953 66.36%
3 spdy/3.1 2858 0.34% 6149508713 11.32%
4 spdy/3 1722 0.20% 6017465564 11.07%
5 h2-14 822 0.10% 5393022646 9.93%
6 h2-16 597 0.07% 5384308586 9.91%
7 h2-15 555 0.07% 5384182462 9.91%
8 h2-fb 195 0.02% 393195293 0.72%
9 grpc-exp 113 0.01% 118456090 0.22%
10 apns-security-v3 16 0.00% 10558487 0.02%
11 apns-pack-v1 16 0.00% 10453570 0.02%
12 http/1.0 155 0.02% 5896305 0.01%
13 spdy/2 669 0.08% 2629459 0.00%
14 ahfs/1.0 11 0.00% 2499626 0.00%
15 spdy/1 564 0.07% 2219037 0.00%
16 h2c 99 0.01% 2204831 0.00%
17 http/0.9 74 0.01% 2171158 0.00%
18 hq 60 0.01% 2170632 0.00%
19 apns-security-v2 3 0.00% 745066 0.00%
20 x-amzn-mqtt-ca 16 0.00% 144403 0.00%