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
165137 0.25% 30618729159 97.88%
2 http/1.1
133713 0.21% 6291977267 20.11%
3 340015 0.52% 6014050187 19.23%
4 h2
h2-fb
http/1.1
34 0.00% 186615870 0.60%
5 grpc-exp
h2
54 0.00% 181484213 0.58%
6 h2
1347 0.00% 128812363 0.41%
7 h2
h2-16
h2-15
h2-14
spdy/3.1
spdy/3
http/1.1
157 0.00% 97447648 0.31%
8 spdy/3.1
spdy/3
http/1.1
60 0.00% 15553706 0.05%
9 h2
spdy/3.1
http/1.1
257 0.00% 9194328 0.03%
10 http/1.1
h2
9196 0.01% 6321316 0.02%
11 apns-security-v3
apns-pack-v1
16 0.00% 3713442 0.01%
12 http/1.1
https/1.1
8 0.00% 3637264 0.01%
13 http/0.9
http/1.0
http/1.1
spdy/1
spdy/2
spdy/3
h2
h2c
hq
28 0.00% 2760211 0.01%
14 http/1.1
http/1.0
42 0.00% 1651646 0.01%
15 hq
h2c
h2
spdy/3
spdy/2
spdy/1
http/1.1
http/1.0
http/0.9
16 0.00% 1417989 0.00%
16 h2
h2-fb
5 0.00% 1136805 0.00%
17 h2
http/1.1
http/1.0
31 0.00% 1100092 0.00%
18 hq
h2c
spdy/3
spdy/2
spdy/1
http/1.0
http/0.9
6 0.00% 551617 0.00%
19 http/0.9
http/1.0
spdy/1
spdy/2
spdy/3
h2c
hq
6 0.00% 550617 0.00%
20 x-amzn-mqtt-ca
37 0.00% 310686 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 fbvp 4 0.00% 260 0.00%
13 h2 1 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 309699 0.48% 37238251268 119.04%
2 h2 176940 0.27% 31236380295 99.85%
3 h2-fb 120 0.00% 187756862 0.60%
4 grpc-exp 96 0.00% 181499661 0.58%
5 spdy/3.1 1180 0.00% 123007568 0.39%
6 spdy/3 792 0.00% 118698981 0.38%
7 h2-14 400 0.00% 97748167 0.31%
8 h2-16 290 0.00% 97523616 0.31%
9 h2-15 286 0.00% 97521363 0.31%
10 http/1.0 176 0.00% 8285933 0.03%
11 spdy/2 491 0.00% 5774378 0.02%
12 h2c 114 0.00% 5584362 0.02%
13 spdy/1 368 0.00% 5537442 0.02%
14 http/0.9 96 0.00% 5530036 0.02%
15 hq 70 0.00% 5517715 0.02%
16 apns-security-v3 17 0.00% 3724468 0.01%
17 apns-pack-v1 17 0.00% 3714627 0.01%
18 https/1.1 8 0.00% 3637264 0.01%
19 quic 37 0.00% 380788 0.00%
20 x-amzn-mqtt-ca 37 0.00% 310686 0.00%