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
 22932642 35.86% 14067711923 66.35%
2 287955 0.45% 3458490644 16.31%
3 http/1.1
 818827 1.28% 3275355337 15.45%
4 grpc-exp
h2
 54 0.00% 96730229 0.46%
5 h2
h2-fb
http/1.1
 34 0.00% 90115923 0.43%
6 h2
h2-16
h2-15
h2-14
spdy/3.1
spdy/3
http/1.1
 154 0.00% 79638530 0.38%
7 h2
 450 0.00% 63204330 0.30%
8 39895484 62.39% 39895968 0.19%
9 spdy/3.1
spdy/3
http/1.1
 57 0.00% 12201368 0.06%
10 h2
spdy/3.1
http/1.1
 261 0.00% 6337535 0.03%
11 http/1.1
h2
 4788 0.01% 3649566 0.02%
12 http/0.9
http/1.0
http/1.1
spdy/1
spdy/2
spdy/3
h2
h2c
hq
 25 0.00% 1765303 0.01%
13 apns-security-v3
apns-pack-v1
 15 0.00% 1680517 0.01%
14 http/1.1
http/1.0
 24 0.00% 1281263 0.01%
15 h2
h2-fb
 5 0.00% 1121156 0.01%
16 hq
h2c
h2
spdy/3
spdy/2
spdy/1
http/1.1
http/1.0
http/0.9
 15 0.00% 890476 0.00%
17 http/1.1
https/1.1
 2 0.00% 836078 0.00%
18 http/0.9
http/1.0
spdy/1
spdy/2
spdy/3
h2c
hq
 5 0.00% 354258 0.00%
19 hq
h2c
spdy/3
spdy/2
spdy/1
http/1.0
http/0.9
 5 0.00% 352917 0.00%
20 h2
http/1.1
http/1.0
 20 0.00% 240052 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 23757890 37.16% 17541233481 82.73%
2 h2 22939020 35.87% 14412183357 67.97%
3 spdy/3.1 1110 0.00% 98833687 0.47%
4 grpc-exp 93 0.00% 96740715 0.46%
5 spdy/3 722 0.00% 95535631 0.45%
6 h2-fb 109 0.00% 91240139 0.43%
7 h2-14 373 0.00% 79913469 0.38%
8 h2-16 272 0.00% 79697398 0.38%
9 h2-15 267 0.00% 79695675 0.38%
10 http/1.0 127 0.00% 5060789 0.02%
11 spdy/2 421 0.00% 3602180 0.02%
12 spdy/1 302 0.00% 3542815 0.02%
13 h2c 100 0.00% 3539154 0.02%
14 http/0.9 86 0.00% 3539066 0.02%
15 hq 64 0.00% 3531285 0.02%
16 apns-security-v3 16 0.00% 1688899 0.01%
17 apns-pack-v1 16 0.00% 1681334 0.01%
18 https/1.1 2 0.00% 836078 0.00%
19 quic 36 0.00% 231027 0.00%
20 x-amzn-mqtt-ca 30 0.00% 167594 0.00%