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
42335 7.71% 20931811891 51.19%
2 497057 90.58% 10981223137 26.85%
3 h2
h2-16
h2-15
h2-14
spdy/3.1
spdy/3
http/1.1
261 0.05% 5199955156 12.72%
4 http/1.1
4451 0.81% 2532638807 6.19%
5 spdy/3.1
spdy/3
http/1.1
110 0.02% 594170790 1.45%
6 h2
h2-fb
http/1.1
31 0.01% 350105614 0.86%
7 h2
spdy/3.1
http/1.1
730 0.13% 108330366 0.26%
8 grpc-exp
h2
67 0.01% 74567528 0.18%
9 h2
288 0.05% 65963615 0.16%
10 spdy/3
http/1.1
372 0.07% 11051515 0.03%
11 apns-security-v3
apns-pack-v1
10 0.00% 9551559 0.02%
12 http/1.1
spdy/3.1
h2-14
h2
109 0.02% 5081005 0.01%
13 h2
h2-fb
10 0.00% 4524637 0.01%
14 h2
h2-16
h2-15
h2-14
http/1.1
22 0.00% 3495712 0.01%
15 h2-16
h2-15
h2-14
h2
spdy/3.1
http/1.1
94 0.02% 3230881 0.01%
16 http/1.1
http/1.0
49 0.01% 2603289 0.01%
17 http/1.1
spdy/3.1
h2
90 0.02% 2342256 0.01%
18 http/1.1
spdy/3.1
143 0.03% 1699959 0.00%
19 h2
spdy/3.1
ahfs/1.0
http/1.1
4 0.00% 1365208 0.00%
20 http/1.1
spdy/3
spdy/3.1
59 0.01% 1250701 0.00%

Selected ALPNs (Server Hello)

Rank ALPN Fingerprints % Fingerprints Connections % Connections
1 600799 76.38% 20149210421 68.01%
2 h2 82538 10.49% 5112282799 17.25%
3 http/1.1 101975 12.96% 4308048506 14.54%
4 grpc-exp 113 0.01% 47270882 0.16%
5 apns-pack-v1:4096:4096 13 0.00% 8183542 0.03%
6 spdy/3.1 1001 0.13% 3596786 0.01%
7 http/1.1 4 0.00% 245712 0.00%
8 h2-fb 7 0.00% 15481 0.00%
9 bep-relay 15 0.00% 13182 0.00%
10 http/1.0 15 0.00% 2019 0.00%
11 fbvp 12 0.00% 1410 0.00%
12 rtmp 5 0.00% 1164 0.00%
13 h2 2 0.00% 1127 0.00%
14 h2-14 71 0.01% 1075 0.00%
15 x-amzn-mqtt-ca 4 0.00% 700 0.00%
16 spdy/3 26 0.00% 288 0.00%
17 bep/1.0 8 0.00% 85 0.00%
18 ncp 2 0.00% 49 0.00%
19 h2-16 8 0.00% 24 0.00%
20 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 49942 9.10% 29757087166 72.77%
2 h2 44574 8.12% 26754051576 65.42%
3 spdy/3.1 2442 0.45% 5923416105 14.48%
4 spdy/3 1273 0.23% 5809001278 14.21%
5 h2-14 788 0.14% 5214913622 12.75%
6 h2-16 566 0.10% 5206998239 12.73%
7 h2-15 526 0.10% 5206865808 12.73%
8 h2-fb 171 0.03% 355087124 0.87%
9 grpc-exp 103 0.02% 74574153 0.18%
10 apns-security-v3 11 0.00% 9737981 0.02%
11 apns-pack-v1 11 0.00% 9664793 0.02%
12 http/1.0 95 0.02% 2616388 0.01%
13 ahfs/1.0 10 0.00% 2190655 0.01%
14 apns-security-v2 3 0.00% 685970 0.00%
15 spdy/2 282 0.05% 434033 0.00%
16 x-amzn-mqtt-ca 11 0.00% 109331 0.00%
17 quic 36 0.01% 58610 0.00%
18 spdy/1 178 0.03% 46831 0.00%
19 HTTP-draft-09/2.0 4 0.00% 38074 0.00%
20 h2c 45 0.01% 37960 0.00%