Solutions
Reference
Learn
Community
/
Log in
Sign Up
Navigate to...
Compute@Edge
Fastly API
Fastly CLI
HTTP references
Image Optimizer
Glossary
Change log
VCL Reference
Declarations
Functions
Operators
Regular expressions
Statements
Subroutines
Types
Variables
Backend connection
Backend request
Backend response
Cache object
Client connection
client.as.name
client.as.number
client.identity
client.ip
client.port
client.requests
client.socket.congestion_algorithm
client.socket.cwnd
client.socket.nexthop
client.socket.pace
client.socket.ploss
client.socket.tcp_info
client.socket.tcpi_advmss
client.socket.tcpi_bytes_acked
client.socket.tcpi_bytes_received
client.socket.tcpi_data_segs_in
client.socket.tcpi_data_segs_out
client.socket.tcpi_delivery_rate
client.socket.tcpi_delta_retrans
client.socket.tcpi_last_data_sent
client.socket.tcpi_max_pacing_rate
client.socket.tcpi_min_rtt
client.socket.tcpi_notsent_bytes
client.socket.tcpi_pacing_rate
client.socket.tcpi_pmtu
client.socket.tcpi_rcv_mss
client.socket.tcpi_rcv_rtt
client.socket.tcpi_rcv_space
client.socket.tcpi_rcv_ssthresh
client.socket.tcpi_reordering
client.socket.tcpi_rtt
client.socket.tcpi_rttvar
client.socket.tcpi_segs_in
client.socket.tcpi_segs_out
client.socket.tcpi_snd_cwnd
client.socket.tcpi_snd_mss
client.socket.tcpi_snd_ssthresh
client.socket.tcpi_total_retrans
fastly_info.edge.is_tls
fastly_info.h2.stream_id
fastly_info.is_h2
fastly_info.is_h3
quic.cc.cwnd
quic.cc.ssthresh
quic.num_bytes.received
quic.num_bytes.sent
quic.num_packets.ack_received
quic.num_packets.decryption_failed
quic.num_packets.late_acked
quic.num_packets.lost
quic.num_packets.received
quic.num_packets.sent
quic.rtt.latest
quic.rtt.minimum
quic.rtt.smoothed
quic.rtt.variance
req.is_ipv6
req.is_ssl
req.protocol
tls.client.certificate.is_cert_bad
tls.client.certificate.is_cert_expired
tls.client.certificate.is_cert_missing
tls.client.certificate.is_cert_revoked
tls.client.certificate.is_cert_unknown
tls.client.certificate.is_unknown_ca
tls.client.certificate.is_verified
tls.client.certificate.raw_certificate_b64
tls.client.cipher
tls.client.ciphers_list
tls.client.ciphers_list_sha
tls.client.ciphers_list_txt
tls.client.ciphers_sha
tls.client.handshake_sent_bytes
tls.client.iana_chosen_cipher_id
tls.client.ja3_md5
tls.client.protocol
tls.client.servername
tls.client.tlsexts_list
tls.client.tlsexts_list_sha
tls.client.tlsexts_list_txt
tls.client.tlsexts_sha
transport.bw_estimate
transport.type
Client request
Client response
Date and time
ESI
Geolocation
Math constants limits
Miscellaneous
Rate limiting
Segmented caching
Server
Waf
Home
Reference documentation
VCL Reference
Variables
Client connection
fastly_info.is_h3
BOOL
, read-only.
Available in
all subroutines
.
Whether or not the request was made using HTTP/3.