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
84053 8.90% 32424224330 55.66%
2 847931 89.80% 14651730479 25.15%
3 h2
h2-16
h2-15
h2-14
spdy/3.1
spdy/3
http/1.1
273 0.03% 5420937066 9.31%
4 http/1.1
6159 0.65% 4322616292 7.42%
5 spdy/3.1
spdy/3
http/1.1
135 0.01% 628183542 1.08%
6 h2
h2-fb
http/1.1
42 0.00% 397045716 0.68%
7 h2
spdy/3.1
http/1.1
754 0.08% 130227572 0.22%
8 grpc-exp
h2
73 0.01% 126972357 0.22%
9 h2
449 0.05% 89672084 0.15%
10 spdy/3
http/1.1
397 0.04% 11679041 0.02%
11 apns-security-v3
apns-pack-v1
17 0.00% 10563085 0.02%
12 http/1.1
spdy/3.1
h2-14
h2
112 0.01% 5746275 0.01%
13 h2
h2-fb
12 0.00% 5165410 0.01%
14 http/1.1
http/1.0
57 0.01% 5005912 0.01%
15 h2
h2-16
h2-15
h2-14
http/1.1
24 0.00% 3549650 0.01%
16 h2-16
h2-15
h2-14
h2
spdy/3.1
http/1.1
100 0.01% 3402467 0.01%
17 http/1.1
spdy/3.1
h2
94 0.01% 2475501 0.00%
18 http/1.1
spdy/3.1
147 0.02% 2053457 0.00%
19 http/1.1
h2
207 0.02% 1866562 0.00%
20 h2
spdy/3.1
ahfs/1.0
http/1.1
4 0.00% 1619390 0.00%

Selected ALPNs (Server Hello)

Rank ALPN Fingerprints % Fingerprints Connections % Connections
1 865719 77.59% 31349552269 72.65%
2 h2 126321 11.32% 6197504725 14.36%
3 http/1.1 122312 10.96% 5538467738 12.83%
4 grpc-exp 116 0.01% 55278347 0.13%
5 apns-pack-v1:4096:4096 15 0.00% 8619659 0.02%
6 spdy/3.1 1016 0.09% 3608731 0.01%
7 http/1.1 5 0.00% 316878 0.00%
8 x-amzn-mqtt-ca 16 0.00% 35865 0.00%
9 h2-fb 7 0.00% 15515 0.00%
10 bep-relay 15 0.00% 14677 0.00%
11 h2 2 0.00% 3860 0.00%
12 http/1.0 16 0.00% 2379 0.00%
13 fbvp 12 0.00% 2009 0.00%
14 ncp 7 0.00% 1522 0.00%
15 rtmp 5 0.00% 1164 0.00%
16 h2-14 72 0.01% 1120 0.00%
17 spdy/3 27 0.00% 291 0.00%
18 bep/1.0 8 0.00% 85 0.00%
19 x-amzn-http-ca 2 0.00% 53 0.00%
20 dot 1 0.00% 25 0.00%
21 h2-16 8 0.00% 24 0.00%
22 acme-tls/1 1 0.00% 2 0.00%
23 http/1.1\x00 1 0.00% 1 0.00%
24 AVTNG 1 0.00% 1 0.00%

Popular ALPNs supported by clients

Rank ALPN Fingerprints % Fingerprints Connections % Connections
1 http/1.1 94135 9.97% 43372116520 74.45%
2 h2 87162 9.23% 38617736547 66.29%
3 spdy/3.1 2978 0.32% 6202550662 10.65%
4 spdy/3 1868 0.20% 6068094161 10.42%
5 h2-14 831 0.09% 5437104505 9.33%
6 h2-16 605 0.06% 5428213222 9.32%
7 h2-15 562 0.06% 5428088859 9.32%
8 h2-fb 204 0.02% 402675573 0.69%
9 grpc-exp 114 0.01% 126981021 0.22%
10 apns-security-v3 18 0.00% 10785970 0.02%
11 apns-pack-v1 18 0.00% 10678139 0.02%
12 http/1.0 200 0.02% 8196208 0.01%
13 spdy/2 807 0.09% 3644709 0.01%
14 spdy/1 696 0.07% 3228892 0.01%
15 h2c 134 0.01% 3212706 0.01%
16 http/0.9 105 0.01% 3178896 0.01%
17 hq 74 0.01% 3177481 0.01%
18 ahfs/1.0 11 0.00% 2596033 0.00%
19 apns-security-v2 3 0.00% 757858 0.00%
20 x-amzn-mqtt-ca 18 0.00% 150488 0.00%