XML compatibility matrix

This document defines the currently supported SIPp subset in Gossipper.

Gossipper process CLI (subcommands, optional gossipper sipp prefix, management server entry, run profiles) is documented in cli.md. This file focuses on XML, keywords, transports, and scenario-time CLI flags parsed after the main dispatcher.

Unsupported XML actions now fail during scenario parsing, and unsupported scenario keywords fail during template rendering instead of silently degrading into no-ops or empty strings.

Commands

SIPp command	Status	Notes
send	supported	UDP and TCP sends; retrans is honored for UDP
recv	supported	Match by request or response; optional receives supported, with pragmatic short-circuit when first incoming SIP mismatches an optional recv
pause	supported	Uses milliseconds, falls back to CLI default
nop	supported	Structural no-op, still participates in branching
label	supported	Used as a target for next jumps
timewait	supported	Executed as a timed pause
sendCmd	supported	Supports local command bus and external peer delivery with dest, Call-ID correlation, and optional From sender identity
recvCmd	supported	Receives from the local bus or external peers, supports actions, timeout, optional src, and first-command correlation adoption for 3PCC-style flows so later [call_id] can reuse the adopted command context
init	supported	Supports initialization nop, pause, label, actions, and command exchange via sendCmd / recvCmd before traffic starts
_unexp.main fallback label	partial	Pragmatic M6 support: on unexpected SIP during recv, if _unexp.main exists, flow jumps there and sets $_unexp.retaddr to the next command index

Common attributes

Attribute	Status	Notes
next	supported	Jumps to a label
test	supported	Evaluated against in-memory variables and action results
chance	supported	Floating point 0..1
condexec	supported	Works with in-memory variables and action results
condexec_inverse	supported	Same behavior as SIPp-style inverted conditional execution
counter	supported	Successful command execution increments the named counter in summary stats
display	supported	Successful command execution increments the named display label in summary stats
start_rtd	supported	Starts a named RTD timer when the command begins execution
rtd	supported	Stops the named RTD timer on successful command completion and aggregates it into summary stats
timeout	supported	Receive timeout in milliseconds
milliseconds	supported	pause and timewait

Scope declarations

Declaration	Status	Notes
Global	supported	Shared variables across calls
User	supported	Variables shared per logical user (-users)
Reference	parsed	Stored for compatibility and future validation

Actions

Action	Status	Notes
ereg	supported	msg, hdr, body, and var search scopes
assign	supported	Assigns a floating-point value from value or variable
assignstr	supported	Assigns rendered string values to variables
todouble	supported	Converts a string variable into a floating-point variable
add	supported	Floating-point arithmetic against assign_to using value or variable
subtract	supported	Floating-point arithmetic against assign_to using value or variable
multiply	supported	Floating-point arithmetic against assign_to using value or variable
divide	supported	Floating-point arithmetic against assign_to using value or variable; divide-by-zero fails the call
strcmp	supported	Lexicographic compare for variable against value or variable2; stores -1, 0, or 1
test	supported	Stores boolean result as 1 or 0; supports value or variable2 with equal, not_equal, greater_than, less_than, greater_than_equal, and less_than_equal
log	supported	Emits message when tracing is enabled
warning	supported	Emits message into the error trace when -trace_err / -error_file is enabled
lookup	partial	Looks up the first CSV column and stores a 1-based physical file line number; integrates with [fieldN ... line=$var]; optional -infindex accelerates key lookups with generated index files
jump	supported	Jumps to an absolute scenario command index via value or variable
gettimeofday	supported	Stores epoch seconds and microseconds in assign_to targets
urlencode	supported	URL-encodes the referenced variable in place
urldecode	supported	URL-decodes the referenced variable in place
verifyauth	supported	Validates incoming Digest Authorization / Proxy-Authorization headers for MD5 and SHA-256 with qop=auth
exec	partial	Supports command, int_cmd, rtp_stream start / pause / resume / stop / echo, pragmatic rtpcheck (min_packets, timeout_ms, `direction=any
sample	partial	Pragmatic deterministic subset: value="min=<int> max=<int> [step=<int>] [seed=<int>]" with assign_to target
insert	partial	Pragmatic CSV field mutation subset: file=... and `value="line= field= text= [position=prefix
replace	partial	Pragmatic CSV field mutation subset: file=... and value="line=<int> field=<int> text=<value>"; affects in-memory [fieldN ...] reads for the current call
setdest	partial	Pragmatic M3 runtime support: updates remote destination for shared-socket UDP flows (u1, ui, server-side UDP aliases), with protocol compatibility validation; non-UDP/per-call transports remain deferred
play_pcap_video	partial	Pragmatic replay support via exec play_pcap_video="capture.pcap" using SDP m=video endpoint discovery and generic RTP payload forwarding
play_pcap_image	partial	Pragmatic replay support via exec play_pcap_image="capture.pcap" using SDP m=image endpoint discovery and generic RTP payload forwarding

Keywords

Keyword	Status	Notes
[service]	supported	CLI -s
[remote_host]	supported	Remote host
[remote_ip]	supported	Resolved remote IP
[remote_port]	supported	Supports +/-offset
[local_ip]	supported	Local bind IP
[local_ip_type]	supported	4 or 6
[local_port]	supported	Supports +/-offset
[transport]	supported	Renders UDP, TCP, or TLS depending on transport; ui explicitly renders as UDP
[call_id]	supported	Generated per call; in command-only/external 3PCC flows it is adopted from the first incoming recvCmd correlation message when needed; SIPp-style prefix///[call_id] form is recognized for dialog correlation (the prefix/// segment is stripped at matching/keying sites)
[cseq]	supported	Basic numeric rendering with offsets
[branch]	supported	Deterministic per message
[len]	supported	Two-pass body length calculation
[call_number]	supported	Monotonic call index
[msg_index]	supported	Scenario message index
[pid]	supported	Current process ID
[last_message]	supported	Last received SIP message
[last_*]	supported	Missing header drops the whole line, matching SIPp semantics
[last_Request_URI]	supported	Uses the last received request URI when available, otherwise falls back to the URI in the last To header
[last_cseq_number]	supported	Extracted from the last CSeq header
[server_ip]	supported	Resolves to the active local bind IP for the call/session; in -t ui server mode it matches the listener IP that accepted the first request for the session
[next_url]	supported	Extracted from the last Contact header
[peer_tag_param]	supported	Extracted from the last To header
[media_ip]	supported	Mirrors local IP for now
[media_ip_type]	supported	Mirrors local IP type
[media_port]	supported	Derived from local SIP port with per-call offset
[rtpstream_audio_port]	supported	Alias for [media_port]; supports +/-offset
[auto_media_port]	supported	Alias for [media_port]; supports +/-offset
[rtpstream_video_port]	supported	[media_port] + 2 (SIPp audio/video offset convention); supports +/-offset
[date]	supported	Current UTC date in RFC2822 form with literal GMT zone (matches SIPp output)
[timestamp]	supported	Current local timestamp
[authentication]	supported	Digest auth for 401/407 challenges with CLI credentials from -au / -ap or inline username= / password= params; supports MD5 and SHA-256 with qop=auth
[fieldN ...]	partial	CSV injection with file= and optional line=; variable-driven form currently uses line=$var, and line numbers are physical 1-based CSV rows
[file ...]	supported	Inlines file contents from scenario-relative or absolute path
[users]	supported	Number of configured logical users from -users
[userid]	supported	Zero-based logical user identifier for the current call
[$n] / [$name]	supported	Action and string variables
[dynamic_id]	supported	Atomic per-message counter with INT32 wraparound to mirror SIPp; supports +/-offset
[routes]	supported	When a recv command uses rrs="true", captured Record-Route headers are replayed as Route headers (reverse order) in subsequent rendered messages
[trunk_from]	supported	Built-in UAC / invite_media: value before ;tag= in From; default gossip <sip:gossip@local_bind:port>; CLI -sip_from
[trunk_pai]	supported	Optional full header line P-Asserted-Identity: … plus CRLF; empty when -sip_pai unset
[trunk_provider]	supported	Optional X-provider: … plus CRLF; empty when -sip_provider unset
[trunk_extra]	supported	Optional extra headers after Via (each line ends with CRLF); repeatable CLI -sip_extra_header
[clock_tick]	supported	Milliseconds elapsed since engine start; supports +/-offset
[sipp_version]	supported	Renders runtime version string (defaults to Gossipper when not explicitly provided)
[tdmmap]	partial	Stub: renders 0.0.0/0; -tdmmap CLI flag is not parsed and per-call slot allocation is deferred
[fill]	supported	variable=N length and optional text="..." seed; matches SIPp behavior

Transport modes

Mode	Status
u1	supported
un	supported
ui	partial (pragmatic client+server multi-IP parity)
s1	supported as server-side UDP alias
sn	supported as server-side UDP alias
sl	supported as server-side TLS alias (normalizes to l1; requires TLS cert/key)
cl	supported as client-side TLS alias (normalizes to l1)
cln	supported as client-side TLS alias (normalizes to ln)
t1	supported
tn	supported
l1	supported
ln	supported

TLS socket modes (SIPp-style)

Relates to issue #7: how SIPp-style TLS mono/multi socket behavior maps to Gossipper.

SIPp-style behavior	Gossipper	Notes
Mono socket: one TLS connection to the remote peer	-t l1 (UAC alias -t cl)	Single shared TLS client (runClientSharedTLS); signaling for all calls is demultiplexed by Call-ID.
Multi socket: one TLS connection per new call, with a cap	-t ln (UAC alias -t cln) and optional -max_socket	Per-call TLS (runClientPerCallTLS); -max_socket limits how many per-call sockets may be open at once (same family as un / tn / ln).
Close TLS when each call ends (multi)	Default for ln / cln UAC	Each call opens a transport.DialogTLS and closes it when that call’s scenario completes (defer dialog.Close() after executeCall). If sockets appear to outlive individual calls, open an issue with version, full CLI, and scenario.

TLS material: UAS needs -tls_cert and -tls_key; UAC often uses -tls_ca and -tls_skip_verify=false for strict verification (default skip is for lab use).

Reconnect: only shared client TCP/TLS (-t t1 / -t l1, or alias -t cl) uses -max_reconnect, -reconnect_sleep, and -reconnect_close on connection loss. Per-call ln / cln does not share that reconnect path.

3PCC CLI workflow

CLI surface	Status	Notes
-cmd_name + -cmd_peers	supported	Low-level external command transport configuration
-master + -slave_cfg	supported	SIPp-style alias for naming the local master instance and peer map
-slave + -slave_cfg	supported	SIPp-style alias for naming the local slave instance and peer map
slave first step validation	supported	-slave scenarios must enter via recvCmd before their first sendCmd
example scenarios	supported	testdata/scenarios/3pcc_master.xml and testdata/scenarios/3pcc_slave.xml

Out-of-call SIP workflow

Workflow	Status	Notes
stateless client send request + recv response	supported	Works for request/response exchanges such as OPTIONS ping
stateless server recv request + send response	supported	Works for responder scenarios such as OPTIONS pong
example scenarios	supported	testdata/scenarios/options_client.xml and testdata/scenarios/options_server.xml

Run control CLI workflow

CLI surface	Status	Notes
-timeout_global	supported	Exits after N seconds of total runtime for deterministic CI/load runs
-rate_scale	supported	Sets interactive CPS step size used by runtime TUI controls (+/- for 1x step and *// for 10x step)
-rate_increase + -rate_interval + -rate_max	supported	Applies periodic CPS ramp-up/ramp-down during run; -rate_max caps upper bound when set
-inf + -ip_field	supported (for -t ui)	With -t ui, -inf is required; -ip_field is optional — when set, selects UI bind IPs from that CSV column (zero-based index). When -ip_field is omitted, bind addresses come from -i (single socket / single listener IP). Client mode preserves CSV row order (including duplicates) for per-call rotation when using a column; server mode binds one listener per unique IP from the column or one listener for -i
-t ui	partial	Pragmatic M3 parity: one UDP shared socket per source IP in client mode and one UDP listener socket per configured IP in server mode; bind failures include failing ip:port; TUI supports ui + inf and optional ip_field; transport token is normalized case-insensitively (for example UI); advanced SIPp parity remains deferred
-infindex	supported	Generates a CSV injection index (-infindex <file> <field>); lookup uses generated index files for faster first-column key resolution
-max_socket	partial	Caps per-call transport concurrency (un, tn, ln, UAC alias cln) by limiting simultaneously open call sockets; parser now rejects unsupported transports early
-max_reconnect + -reconnect_sleep + -reconnect_close	partial	Shared client TCP/TLS (t1, l1, or UAC alias cl that normalizes to l1) support reconnect retries and close-on-reconnect; per-call ln/cln does not; see TLS socket modes

Trace CLI workflow

CLI surface	Status	Notes
-trace_msg	supported	Writes full sent/received messages to the configured file
-message_file	supported	Explicit path for the full message trace log; also enables -trace_msg
-trace_shortmsg	supported	Writes a compact CSV sibling log with timestamp, direction, protocol, summary, and Call-ID
-trace_counts	supported	Writes periodic CSV snapshots with per-scenario SIP command counters (sent, recv, unexp); additional per-message detail is intentionally deferred to keep schema stable in M5
-trace_stat	supported	Writes periodic and final CSV stats snapshots to a sibling _stats trace file with both cumulative totals and per-interval delta fields
-fd	supported	Controls -trace_stat snapshot frequency in seconds (SIPp-compatible naming); providing -fd also enables -trace_stat
-trace_rtt	supported	Writes each completed named RTD sample to a sibling _rtt CSV trace file
-rtt_freq	supported	Controls -trace_rtt flush cadence in completed calls (default 200); providing -rtt_freq also enables -trace_rtt
CSV schema contract	supported	Stable -trace_stat / -trace_rtt / -trace_screen header contract is documented in docs/trace-schema-contract.md
legacy trace CSV alias columns	deferred	Not emitted by design; migration should use explicit parser adapters, see docs/trace-schema-contract.md
-trace_err	supported	Writes unexpected SIP messages and runtime failures to the configured error file
-error_file	supported	Explicit path for the error trace log; also enables -trace_err
-trace_error_codes	supported	Writes a compact sibling CSV file with unexpected SIP response codes, reasons, Call-ID, and expected match
-trace_screen	supported	Writes periodic non-interactive runtime summary snapshots to a screen CSV log with success ratio, interval throughput, and key failure counters
-screen_file	supported	Explicit path for the screen snapshot log; also enables -trace_screen
SIGUSR1 screen dump trigger	supported	Forces an immediate runtime screen snapshot when -trace_screen is enabled
-trace_logs	supported	Writes XML action <log> output to a dedicated file
-log_file	supported	Explicit path for the action log trace file; also enables -trace_logs

Statistics export

Export surface	Status	Notes
summary JSON failure classes	supported	Exports failure class counters such as timeout, unexpected_sip, transport_error, parse_error, scenario_error, and cancelled
-trace_stat failure class columns	supported	Periodic stats CSV includes cumulative and delta columns for the same failure classes
summary JSON latency repartition	supported	Exports call_length, invite_rtt, and named rtd summaries with stddev and repartition buckets
-trace_stat latency stddev columns	supported	Periodic stats CSV includes call and invite latency standard deviation columns
SIPp stats field mapping doc	supported	See docs/statistics-mapping.md for the current field-by-field correspondence and gaps

HEP CLI workflow

CLI surface	Status	Notes
-hep_addr	supported	Mirrors SIP send / recv messages to a Homer-compatible HEP3 UDP collector
-hep_capture_id	supported	Sets the HEP capture node ID
-hep_password	supported	Sets the optional HEP auth key
RTP/RTCP mirroring	deferred	Current HEP MVP exports SIP signaling only

Media and SRTP (scenario-time)

CLI surface	Status	Notes
-media_srtp	supported	When peer SDP offers SRTP: SDES (a=crypto:) and/or DTLS-SRTP (a=fingerprint:); encrypt RTP/SRTCP outbound, decrypt inbound; see docs/srtp.md, docs/rtp-in-scenarios.md
-media_reject_srtp	supported	Fail rtp_stream / mic when SDP hints SRTP (cleartext-only runs)
-turn_server, -turn_user, -turn_pass, -turn_realm	partial	UDP TURN relay for ICE typ relay paths when using -media_srtp; not a full browser ICE stack

Authentication CLI workflow

CLI surface	Status	Notes
-au	supported	Authorization username; defaults to -s value like SIPp
-ap	supported	Authorization password; defaults to password like SIPp
-base_cseq	supported	Sets the base value used by [cseq] token rendering
-rp	supported	SIPp-style rate period for -r (n calls per rp milliseconds)
runtime interactive rate keys (+, -, *, /)	supported	TUI adjusts target CPS by -rate_scale (+/-: 1x, *//: 10x)
-reconnect_close	partial	In shared client t1/l1, closes active calls by disabling reconnect attempts when a socket loss is detected
challenged request retry via [authentication]	supported	Works for Digest 401 / 407 flows when the scenario explicitly places [authentication] in the retried request

Deliberately deferred

• advanced insert / replace semantics beyond current deterministic per-cell CSV mutation subset
• advanced sample distributions beyond current deterministic integer range subset
• broader per-call addressing changes outside current setdest pragmatic scope (for example per-call sockets and non-UDP transports)
• full video/image media pipeline parity beyond pragmatic PCAP replay coverage
• advanced -t ui parity beyond current client+server multi-IP MVP (broader SIPp behavior alignment)
• keyword helpers such as [tdmmap] and advanced [fill] semantics beyond the current pragmatic subset
• full SIPp rtpcheck parity (Gossipper's rtpcheck is pragmatic RTP activity validation; not full SIPp SRTP/QoS metrics)
• full CLI parity with SIPp