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Compute@Edge
Fastly API
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Declarations
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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.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
transport.bw_estimate
INTEGER
, read-only.
Available in
recv
hash
deliver
log
Estimation of the bandwidth (bytes per second).