fips/docs/reference/transports.md

Transport Statistics Reference

Per-transport statistics counter inventories. Counters are exposed through the daemon control socket (fipsctl show transports) and the fipstop operator UI. For the transport-layer design (services provided to FMP, transport categories, the trait surface, connection model), see ../design/fips-transport-layer.md.

All transports report counters via fipsctl show transports; the tables below are source-extracted from each transport's stats.rs module.

UDP

Counter	Description
packets_sent / bytes_sent	Successful sends
packets_recv / bytes_recv	Successful receives
send_errors / recv_errors	Send/receive failures
mtu_exceeded	Packets rejected for MTU violation
kernel_drops	Kernel SO_RXQ_OVFL drop count (feeds ECN congestion detection)

TCP

Counter	Description
packets_sent / bytes_sent	Successful sends
packets_recv / bytes_recv	Successful receives
send_errors / recv_errors	Send/receive failures
mtu_exceeded	Packets rejected for MTU violation
connections_established	Successful outbound connections
connections_accepted	Accepted inbound connections
connections_rejected	Rejected inbound connections (either limit exceeded)
source_rejected	Inbound connections rejected because their source (one IPv4 address or IPv6 /64) already held max_inbound_per_source connections; also counted in connections_rejected
connect_timeouts	Connection timeout count
connect_refused	Connection refused count
pool_inbound	Current inbound connections held in the connection pool (gauge)
pool_outbound	Current outbound connections held in the connection pool (gauge)

Ethernet

Counter	Description
frames_sent / frames_recv	Successful frame send/receive
bytes_sent / bytes_recv	Byte counters
send_errors / recv_errors	Send/receive failures
beacons_sent / beacons_recv	Peer-discovery beacon traffic
beacons_dropped	Received beacons the discovery buffer had no room for
frames_too_short	Frames below minimum length, dropped
frames_too_long	Frames above transport MTU, dropped

Tor

Counter	Description
packets_sent / bytes_sent	Successful sends
packets_recv / bytes_recv	Successful receives
send_errors / recv_errors	Send/receive failures
connections_established	Successful SOCKS5 connections
connect_timeouts	Connection timeout count
connect_refused	Connection refused count
socks5_errors	SOCKS5 protocol errors
mtu_exceeded	Packets rejected for MTU violation
connections_accepted	Accepted inbound connections via onion service
connections_rejected	Rejected inbound connections (limit exceeded)
control_errors	Tor control port errors
pool_inbound	Current inbound connections held in the connection pool (gauge)
pool_outbound	Current outbound connections held in the connection pool (gauge)

Nym

Counter	Description
packets_sent / bytes_sent	Successful sends
packets_recv / bytes_recv	Successful receives
send_errors / recv_errors	Send/receive failures
mtu_exceeded	Packets rejected for MTU violation
connections_established	Successful SOCKS5 connections through nym-socks5-client
connect_timeouts	Connection timeout count
socks5_errors	SOCKS5 protocol errors

Nym is outbound-only (no inbound listener), so there are no connections_accepted / connections_rejected counters.

Bluetooth

Counter	Description
packets_sent / bytes_sent	Successful L2CAP CoC sends
packets_recv / bytes_recv	Successful L2CAP CoC receives
send_errors / recv_errors	Send/receive failures
mtu_exceeded	Packets rejected for MTU violation
connections_established	Successful outbound L2CAP connections
connections_accepted	Accepted inbound L2CAP connections
connections_rejected	Links a full pool refused (inbound, dialled or probed)
handshakes_aborted	Inbound handshakes aborted to free an in-flight slot
connect_timeouts	Connection timeout count
connect_errors	Outbound connects that failed with an error rather than timing out
pubkey_exchange_failures	Connections dropped because the pre-handshake pubkey exchange failed
pool_evictions	Connection-pool entries evicted
advertisements_sent	BLE advertisements emitted
scan_results	BLE scan results observed
duplicate_node_declines	Connections declined beside another link to the same node: a verified one at any link address, or an unverified one at the same link address or still racing the newcomer in the opposite direction
duplicate_link_replacements	Links replaced by a racing second link to the same peer: both ends keep the one the smaller node dialled

See also

• ../design/fips-transport-layer.md — transport-layer design, trait surface, per-transport sections
• configuration.md — transports.* configuration blocks
• ../how-to/tune-udp-buffers.md — host-side net.core.rmem_max / net.core.wmem_max setup for UDP
• ../how-to/deploy-tor-onion.md — Tor directory mode operator setup
• ../how-to/set-up-bluetooth-peer.md — Linux BLE peer config