larvit/smpp-js
3
0
Fork 0
Code Issues Pull Requests Actions Activity
Files
84dcf4f3ec53aae46c4075252e098a4113e73f0c
smpp-js/interop-tests/research/esme-clients-and-validators.md
T

36 KiB
Raw Blame History

SMPP ESME clients, load generators, and independent PDU validators — interop-testing @larvit/smpp

Research note: this session's shared WebSearch budget (200 calls, spent across parallel research threads on this task) was exhausted partway through. Sections B and C below are fully search-backed. Section A was completed with WebFetch only (direct GitHub API / raw-file / PyPI / crates.io / RubyGems / Hex.pm requests) after the search budget ran out and a parallel research agent covering Go/Erlang/other-language clients was lost to a session rate limit. Where a claim could not be independently re-verified this session, it is marked unverified rather than guessed — this hits Kannel hardest (see A18): kannel.org's TLS certificate failed validation on every fetch attempt this session, so its exact config keys could not be re-confirmed against a live primary source.

A. ESME client libraries / tools

Summary

# Library Language Licence Repo Last activity Maintained?
A1 Cloudhopper SMPP Java Apache-2.0 per README; GitHub shows NOASSERTION fizzed/cloudhopper-smpp (fork of twitter-archive/cloudhopper-smpp, archived) fork: no commits since 2018-10-03, issues triaged to 2026-08-24; original archived 2021-08-18 Fork only, lightly
A2 jsmpp Java Apache-2.0 opentelecoms-org/jsmpp pushed 2026-06-17, 68 open issues Yes
A3 OpenSMPP (Logica) Java BSD (per README) OpenSmpp/opensmpp pushed 2023-11-01 Weakly
A4 python-smpplib Python LGPL-3.0 python-smpplib/python-smpplib PyPI 2.2.4, 2025-01-17 Yes
A5 smpp.twisted Python LICENSE file present, text unverified jookies/smpp.twisted 7 commits total Stable/frozen
A6 smpp.pdu Python LICENSE file present, text unverified jookies/smpp.pdu 7 commits, 2 open issues Stable/frozen
A7 Jasmin (smppccm) Python/Twisted NOASSERTION on GitHub jookies/jasmin pushed 2026-04-26 Yes
A8 fiorix/go-smpp Go MIT fiorix/go-smpp pushed 2026-04-25 Yes
A9 linxGnu/gosmpp Go Apache-2.0 linxGnu/gosmpp pushed 2026-07-13, 21 open issues Yes
A10 oserl Erlang unverified archaelus/oserl last updated 2009-04-03 No — frozen, embedded in smppload
A11 libsmpp34 C LGPL-2.1 osmocom/libsmpp34 pushed 2026-08-20 Yes
A12 smpp34 (crate) Rust unverified crates.io/crates/smpp34 v1.4.1 on crates.io unverified
A13 JamaaSMPP C# unverified AdhamAwadhi/JamaaSMPP pushed 2026-08-18 Yes
A14 php-smpp PHP none declared alexandr-mironov/php-smpp (fork of OnlineCity/php-smpp, unmaintained) fork pushed 2022-12-02 Weakly
A15 Net::SMPP Perl unknown metacpan.org/pod/Net::SMPP v1.19, 2011-06-01 No
A16 ruby-smpp Ruby unverified rubygems.org/gems/ruby-smpp v0.6.0, 108,794 downloads unverified
A17 smppex Elixir unverified hex.pm/packages/smppex v3.3.0, updated ~2 months ago Yes
A18 Kannel bearerbox (SMPP client) C Kannel Software License 1.0 (Apache-1.1-like) kannel.org — canonical source unreachable this session unverified this session unverified this session

A1. Cloudhopper SMPP

fizzed/cloudhopper-smpp is the maintained fork of Twitter's archived twitter-archive/cloudhopper-smpp (archived 2021-08-18). The fork itself has had no new commits since 2018-10-03 but still receives issue triage (last activity 2026-08-24, 24 open issues) — treat as lightly maintained, not actively developed. Netty-based session library.

  • Docker: no official image. Build from source with Maven inside a JDK image you pin yourself (never guess a tag) — the repo's own instructions run demos via make client/make server wrapping the Maven build.
  • Bind/send (from the demo client, ClientMain.java): 
    config0.setSystemId("1234567890");
config0.setPassword("password");
config0.setType(SmppBindType.TRANSCEIVER);
config0.setWindowSize(1);
config0.setRequestExpiryTimeout(30000);
config0.setWindowMonitorInterval(15000);
SubmitSm submit0 = new SubmitSm();
submit0.setShortMessage(textBytes);
session0.submit(submit0, 10000);
    systemType/interfaceVersion are not set in the demo (library defaults apply — not confirmed further this session).
  • Encoding: demo encodes with CharsetUtil.encode(text160, CharsetUtil.CHARSET_GSM) for data_coding 0. Packed vs. unpacked septets not confirmed from the demo alone — unverified.
  • Long messages: demo sends a single ≤160-char GSM segment only; no UDH/SAR/message_payload shown — unverified whether the library auto-splits.
  • enquire_link: demo only sends it synchronously on a keypress (session0.enquireLink(new EnquireLink(), 10000)); no periodic automatic keepalive demonstrated.
  • Windowing: first-class — setWindowSize(), setRequestExpiryTimeout(), setWindowMonitorInterval() are real, documented session-config knobs. This is the strongest windowing/backpressure story of any Java client here.
  • Strictness / quirk: twitter/cloudhopper-smpp#39 — a user reports throughput capped at ~200 msg/s even after raising window size ("window wait time is always zero"), i.e. windowing alone won't reveal a throughput bug if your server's per-PDU response latency dominates. Unresolved, on an archived repo.

A2. jsmpp

opentelecoms-org/jsmpp, Apache-2.0, actively maintained (pushed 2026-06-17). README: "supports SMPP v3.3, v3.4 and v5.0" and explicitly "is not a high-level library" — it does not auto-split long messages; the caller owns UDH/SAR/message_payload chunking, which makes it good for controlled wire-level testing.

  • interface_version negotiation (confirmed directly from SMPPSession.java): 
    InterfaceVersion commonInterfaceVersion = scVersion != null
    ? InterfaceVersion.IF_50.min(InterfaceVersion.valueOf(scVersion.getValue()))
    : InterfaceVersion.IF_34;
    If the server's bind_resp omits the sc_interface_version optional TLV, jsmpp silently assumes 3.4 — it never rejects a bind over a missing/absent TLV. If the TLV is present with a value InterfaceVersion.valueOf() doesn't recognize, that call is an enum-style lookup that can throw — a server sending a bogus sc_interface_version byte is a good way to probe jsmpp-based tooling for a crash vs. graceful handling.
  • Docker: no official image found — unverified; build with Maven/Gradle inside a self-pinned Java image.
  • Long message / encoding: the bundled StressClient.java example hardcodes DataCodings.ZERO and calls submitShortMessage() directly — no UDH/SAR/message_payload, confirming the library leaves long-message strategy entirely to the caller.
  • enquire_link: known quirk — opentelecoms-org/jsmpp#142 "Enquire time not respected?" reports the library's enquire-link-interval not firing as configured.
  • Windowing: no true max-outstanding window found in the stress example (maxOutstanding there is a fixed thread-pool size for response processing, not a protocol window) — unverified whether the core session API exposes a real window elsewhere.

A3. OpenSMPP (Logica)

OpenSmpp/opensmpp, Java, pushed 2023-11-01. Per its README: "originally issued under the Logica Open Source License Version 1.0, but was subsequently put in the public domain under the current BSD licence." This is the historical root that much SMPP tooling's PDU model descends from. Related forks found: cornet/logica-smpp and a companion simulator cornet/logica-smscsim (server-side, out of scope here). Bind/send example, Docker packaging, long-message defaults, encoding, and enquire_link behaviour were not independently re-verified this session (search budget exhausted before a source read) — mark all operational specifics unverified.

A4. python-smpplib

python-smpplib/python-smpplib, LGPL-3.0 (confirmed via both GitHub API and the PyPI JSON API: latest 2.2.4, released 2025-01-17).

  • Bind: client.bind_transmitter(**kwargs) / bind_transceiver(**kwargs) — system_id/password/system_type/interface_version all pass through as kwargs into the PDU (confirmed from smpplib/client.py).
  • Encoding — notable: smpplib/consts.py defines SMPP_ENCODING_DEFAULT = 0x00. smpplib/gsm.py's gsm_encode() maps each character to one unpacked byte (with \x1B-escape for the extension table) rather than packing 8 characters into 7 septet bytes: 
    def gsm_encode(plaintext):
    return b''.join(
        six.int2byte(index) if index < 0x80 else b'\x1B' + six.int2byte(index - 0x80)
        for index in map(GSM_CHARACTER_TABLE.index, plaintext))
    This is a real cross-check opportunity: if @larvit/smpp decodes data_coding 0 as standard packed 7-bit, a raw submit_sm from this client will decode as garbage unless the harness explicitly unpacks/repacks — worth testing deliberately either way.
  • Long messages: make_parts_encoded() in the same file builds UDH concatenation (\x05\x00\x03 + random ref id + total-parts + this-part), i.e. UDH is the default splitting method, not sar_*/message_payload.
  • enquire_link: opt-in and reactive, not a fixed timer — on a socket read timeout, if auto_send_enquire_link is set the client sends enquire_link instead of raising; otherwise it re-raises the timeout.
  • Docker: no official image; python:3.12.14-slim-bookworm (verified current full-patch tag via Docker Hub's tag API as of this research) + pip install smpplib is a safe base.

A5–A6. Jasmin's smpp.twisted / smpp.pdu

jookies/smpp.twisted (Twisted-based SMPP 3.4 client/session engine) and jookies/smpp.pdu (the PDU encode/decode layer underneath it) are Jasmin's internal SMPP engine, each with only 7 commits on master — essentially frozen/stable rather than actively developed, which is consistent with being a settled dependency rather than a product. Both repos confirm a LICENSE file exists but its exact text wasn't fetched this session — unverified licence specifics. TLV/long-message/encoding details for these two packages specifically were not independently confirmed this session — for practical testing, use them via Jasmin itself (A7) rather than standalone.

A7. Jasmin SMPP client connector (smppccm)

jookies/jasmin, GitHub shows licence NOASSERTION (a LICENSE file exists in-repo; exact terms not re-confirmed this session), actively maintained (pushed 2026-04-26).

  • Docker: official image jookies/jasmin on Docker Hub. Tag listing shows the latest tagged release is 0.11.0 (pushed 2023-11-10) — use jookies/jasmin:0.11.0. Note the image lags the git repo (repo pushed as recently as 2026-04-26, image not retagged since 2023).
  • Configuring + driving smppccm (exact key names confirmed from source, jasmin/protocols/cli/smppccm.py — full key list: cid, host, port, username, password, systype, bind, bind_ton, bind_npi, logfile, loglevel, logrotate, logprivacy, bind_to, elink_interval, res_to, pdu_red_to, trx_to, con_loss_retry, con_loss_delay, con_fail_retry, con_fail_delay, src_addr, src_ton, src_npi, dst_ton, dst_npi, addr_range, proto_id, priority, validity, ripf, def_msg_id, coding, requeue_delay, submit_throughput, dlr_expiry, dlr_msgid, ssl, custom_tlvs): 
    jcli
smppccm -a
cid myconnector
host <target-host>
port <target-port>
username <system_id>
password <password>
bind transceiver
ok
smppccm -1 myconnector
    To actually push a submit_sm, Jasmin doesn't send it from a jCli command directly — you add an MT route (mtrouter -a) pointing traffic at the connector, then trigger it via Jasmin's own HTTP send API (GET/POST /send), which the MT router forwards to the connector as an outbound submit_sm.
  • enquire_link: elink_interval config key controls the periodic timer per-connector — confirmed directly from source.
  • Windowing: only submit_throughput (a rate cap) was found in the confirmed key list — no distinct max-outstanding-window key surfaced. Unverified whether one exists elsewhere in the connector implementation.
  • Long messages / encoding: coding sets the connector's default data_coding; long-message splitting strategy inherited from smpp.pdu/smpp.twisted beneath it — not independently confirmed this session.
  • Being Python/Twisted and used in real MNO/aggregator deployments, Jasmin exercises a genuinely different stack/style from every Java option here — see recommendation notes below.

A8. fiorix/go-smpp

fiorix/go-smpp, MIT, active (pushed 2026-04-25). Ships a one-shot CLI, cmd/sms (sms send <from> <to> <text>, env SMPP_USER/SMPP_PASSWD, flags --addr/--tls) — good for a single bind+submit+deliver smoke test, not a load driver (no count/rate/window flags). Long-message default, data_coding behaviour, enquire_link interval, and windowing were not independently confirmed this session beyond the CLI's absence of relevant flags — unverified at the library level.

A9. linxGnu/gosmpp

linxGnu/gosmpp, Apache-2.0, active (pushed 2026-07-13, 21 open issues), described in its own README as "porting from Java OpenSMPP Library." Bind example:

trans, err := gosmpp.NewSession(
    gosmpp.TRXConnector(gosmpp.NonTLSDialer, auth),
    gosmpp.Settings{ /* EnquireLink: 5*time.Second, OnPDU, OnClosed, ... */ },
    5*time.Second)

Settings.EnquireLink sets a real periodic keepalive interval; OnClosed/rebind hooks suggest built-in auto-reconnect behaviour on connection loss (worth probing — does it reconnect and rebind automatically if your server closes on idleTimeout?). Supported-PDU list includes submit_sm_multi/data_sm; exact UDH/SAR default-splitting and data_coding behaviour not confirmed from the README excerpt fetched — unverified. No bundled load tool.

A10. oserl

Canonical repo archaelus/oserl — "Enrique Marcote Peña's SMPP for Erlang (mirrored from sourceforge with minor patches)," last updated 2009-04-03: effectively abandoned for 15+ years. Its practical relevance today is that PowerMeMobile's smppload (Section B) depends on it under the hood (per smppload's rebar.config). Minor satellites found: dergraf/smpp (2011, thin Erlang wrapper) and netDalek/smppex_oserl (2019, Elixir SMPPEX↔oserl PDU converter). Treat oserl as "the engine inside smppload," not a library to stand up fresh — use smppload itself, or smppex (A17) for a genuinely maintained Erlang-VM option.

A11. libsmpp34

osmocom/libsmpp34 (mirrored from gitea.osmocom.org), C, LGPL-2.1, actively maintained (pushed 2026-08-20, i.e. 16 days before this research). It's a PDU encode/decode codec used inside Osmocom's telecom stack (e.g. OsmoSMSC), not a ready bind/submit/receive CLI. Docker packaging, long-message defaults, and encoding behaviour need a source read not completed this session — unverified.

A12. Rust: smpp34 crate

Of the Rust crates found on crates.io — smpp (client+server, v0.1.2), smpp34 ("Pure-Rust SMPP 3.4 codec with an async (tokio) client and server", v1.4.1), smpp-pdu (parsing only, v0.1.4), smpp-codec (SMPP v5 codec, v0.2.1), and the rusmpp/rusmppc/rusmppz/rusmpp-macros family (all v0.4.0, modular core + a dedicated client crate rusmppc) — smpp34 is the most complete single credible pick (highest version number, explicit client+server+async claim). Repo URL, licence, and operational details (bind example, long-message/encoding defaults) were not independently fetched this session beyond the crates.io registry metadata — unverified; read its crates.io page/repo before relying on it.

A13. C#: JamaaSMPP

AdhamAwadhi/JamaaSMPP, a fork/continuation of the original Jamaa Technologies SmppClient, actively maintained (pushed 2026-08-18). NuGet: Install-Package JamaaSMPP. README confirms: concatenated/long-message handling via UDH, SAR, and message_payload — all three, developer's choice; GSM 03.38 alphabet encoding; custom encoding configurable per client instance; separate-or-combined TX/RX connections. v2.0.0 dropped .NET Framework 4.0 and reworked response-handler threading reliability (worth checking current issues for residual races — not reviewed this session). Licence not confirmed this session — unverified, check the repo's LICENSE before adoption.

A14. PHP: php-smpp

Original OnlineCity/php-smpp (pushed 2022-09-18, no licence declared) explicitly states in its README: "THIS REPO IS NO LONGER MAINTAINED!", pointing to the fork alexandr-mironov/php-smpp (pushed 2022-12-02, 6 open issues, also no licence declared — flag this as a legal gap before adopting either).

  • Bind: bindTransmitter() / bindReceiver() with host/port/username/password. No bind_transceiver support — README: "You can't connect as a transceiver, otherwise supported by SMPP v.3.4." This forces you to run separate TX and RX connections against the server under test, directly exercising direction-enforcement (e.g. your server's ESME_RINVBNDSTS handling) on genuinely separate binds rather than one combined TRX session.
  • submit_sm: sendSMS().
  • Long messages: three built-in modes — CSMS_16BIT_TAGS, CSMS_PAYLOAD (message_payload), CSMS_8BIT_UDH — the broadest single-library choice of long-message wire strategy found in this research.
  • Encoding: assumes GSM 03.38; ships GsmEncoder::utf8_to_gsm0338().
  • enquire_link: application-driven on an inactivity timeout (README example: "every 30 seconds of inactivity"), not automatic by default.

A15. Perl: Net::SMPP

metacpan.org/pod/Net::SMPP, last release 1.19, 2011-06-01 — unmaintained 14+ years, licence unknown per MetaCPAN.

  • bind_transceiver() and submit_sm() documented directly.
  • Long messages: docs recommend message_payload for bodies over 254 bytes (leaving short_message empty) — its documented path is message_payload, not UDH/SAR.
  • Encoding: explicitly does not auto-encode — "Net::SMPP also does not automatically perform the encoding" — ships pack_7bit()/unpack_7bit() helpers the caller must invoke explicitly. Useful precisely because you control packed-vs-unpacked GSM 7-bit deliberately, letting you test both against the server on purpose.

A16. Ruby: ruby-smpp

ruby-smpp (EventMachine-based), v0.6.0, 108,794 downloads — the most-downloaded of seven SMPP-related Ruby gems found, ahead of its own fork anjlab-ruby-smpp (33,740 downloads, v0.6.4) and smaller options (smpp_encoding, rocket_sms, Crota, rock-queue-smpp, anthill_smpp_ruby). Bind/long-message/encoding specifics not independently fetched this session beyond gem metadata — unverified.

A17. Elixir: smppex

smppex on hex.pm, "SMPP 3.4 protocol and framework implemented in Elixir," v3.3.0, updated roughly 2 months before this research, 200,620 total downloads — clearly the maintained choice over esmpp (v0.0.13, ~9 years stale) and the companion smppex_telemetry package (~5 years stale, but its existence confirms a real surrounding ecosystem). Bind/config specifics not independently fetched this session — unverified.

A18. Kannel bearerbox as an SMPP client

Kannel is confirmed (via Wikipedia) to be licensed under the "Kannel Software License 1.0" (Apache-1.1-like), official site kannel.org. This session could not independently verify any operational SMPP-client detail: every fetch attempt against kannel.org's user guide failed with a TLS certificate validation error, and no working canonical GitHub/GitLab mirror of the primary (historically SVN-hosted) repo was confirmed — third-party forks found (e.g. pruiz/kannel) are stale (last touched 2014) and not authoritative. The well-known architecture (a group = smsc / smsc = smpp config stanza binding bearerbox as an SMPP client, driven by smsbox's HTTP sendsms interface) is widely documented under normal circumstances, but restating its exact config keys from memory here would violate this report's "verify or mark unverified" rule — treat all Kannel specifics as unverified pending a follow-up session with working TLS to kannel.org (or a fixed CA bundle).

B. Load / soak generators

(Fully researched with WebSearch+WebFetch by a parallel research thread this session.)

Summary

Tool Repo Licence Language Maintained?
smppload PowerMeMobile/smppload none found Erlang Sporadic (tags 2014→2.5.3; 1 open issue since 2023)
SMPPSim e.g. haifzhan/SMPPSim (unofficial mirror) custom freeware, non-OSI Java Server-only — not a client load tool
fiorix/go-smpp (cmd/sms) fiorix/go-smpp MIT Go Active, but one-shot only, no load mode
linxGnu/gosmpp linxGnu/gosmpp Apache-2.0 Go Active; no bundled load tool
veoo/smpperf veoo/smpperf MIT Go Dead since 2020-06-10; sends one message and exits despite the name
vponomarev/libsmpp (smpp-dumb-client) vponomarev/libsmpp LGPL-3.0 Go Low activity (2025-07-01) — the one Go tool with a real bounded window
AShabana/smpp-load-test AShabana/smpp-load-test none found Go Dead since 2022-08-10
cloudhopper-smpp (library) fizzed/cloudhopper-smpp Apache-2.0 per README Java Basis for bespoke load tools, not one itself
Java-SMPP-Load-GUI shaf2k/Java-SMPP-Load-GUI none found Java Dead, 1 commit (2015)
jsmpp StressClient/StressServer opentelecoms-org/jsmpp Apache-2.0 Java Active; bundled example, not a packaged tool
wizardjedi/smpp-test-tools wizardjedi/smpp-test-tools none found Java Low activity (2023-02-23)
emgload/emgsink smpp.com/smpp-benchmarking.html proprietary native, unverified Actively sold
Melrose Labs Load Test Tool melroselabs.com/tools/smpploadtest proprietary, hosted n/a Active service

smppload (PowerMeMobile) — the practical free/open pick

  • CLI: -H/--host -P/--port -B/--bind_type(TX|TRX|RX) -i/--system_id -p/--password -r/--rps(1000) -T/--thread_count(10) -c/--count(1) -s/--source -d/--destination -l/--length(140) -D/--delivery -C/--data_coding(3=Latin1) (from src/smppload.erl): 
    smppload -H smsc.example.com -P 2775 -B trx -i myuser -p mypass \
  -s 1234:1,1 -d 15555550100 -c 100000 -r 500 -T 20 -l 140 -D 1
  • Windowing: no true bounded in-flight window — "window" is really thread_count × rps (confirmed from smppload_esme.erl).
  • Throttling: all non-zero command_status responses fold into one send_fail counter (smppload_stats.erl) — no ESME_RTHROTTLED-specific backoff.
  • Long messages: yes, UDH-based multipart; UCS2-BE for Unicode.
  • enquire_link: not implemented at all.
  • Docker: no official image; needs a hand-built Erlang/OTP 19+ image, tag chosen and pinned by you.
  • Known issues: #8 rebar3/BEAM load errors (open); a closed issue documents Erlang 22.3.2 compile failures.

The one tool with a real bounded window: vponomarev/libsmpp's smpp-dumb-client

YAML-driven (config.yml):

smpp:
  remote: 127.0.0.1:2500
  bind: { systemID: test, systemType: test, password: test, mode: TRX }
generator:
  enabled: yes
  count: 0       # total messages
  rate: 100      # messages/sec
  window: 2000   # max outstanding unacked submit_sm — real, enforced
  stayConnected: yes

Confirmed enforced in generator.go: sending is skipped once in-flight count reaches window. No ESME_RTHROTTLED-aware backoff; no long-message (UDH/SAR) support; plain ShortMessage body only. Same repo also ships a matching test SMSC (smpp-dumb-server) and an smpp-lb load balancer.

SMPPSim — out of scope as a client tool

Confirmed server-only from its official README: "a testing utility which mimics the behaviour of an SMPP based SMSC." No client-side load mode exists. Docker mirrors found (balsagoth/smppsim last pushed 2017-08-03; jookies/smppsim last pushed 2022-08-07) are unofficial and stale.

Other notes

  • Cloudhopper's demo (ClientMain.java) has real windowing (setWindowSize) but is a one-message demo, not a load driver; a bespoke load tool would need to be built on top.
  • jsmpp's StressClient/StressServer examples (source) fire bulkSize (default 100,000) submits bounded only by a pduProcessorDegree-sized thread pool — no rate control, no long messages, no differentiated throttle handling.
  • emgload/emgsink (smpp.com) is the one tool here with explicit UDH-via-TLV long-message load support (--smpp_udh_via_optional) and very high claimed throughput (~25,000 msg/s), but it's commercial (~599 EUR/yr/host, unlicensed use capped at 10 msg/s) and closed-source.
  • Melrose Labs' hosted Load Test Tool exposes TPS, concurrent binds, a distinct "submit window," message quantity, and long-message splitting all as separate dials — useful as terminology/prior-art confirmation that "window" and "rate" are properly orthogonal knobs, even though it's not automatable in CI (paid, web-UI only).

Bottom line for Section B: smppload is the only free, scriptable, protocol-real load generator with long-message support; pair it with vponomarev/libsmpp's smpp-dumb-client specifically when you need to test a genuine bounded-window/backpressure scenario against maxOutstanding, since smppload cannot do that.

C. Independent PDU validators

(Fully researched with WebSearch+WebFetch by a parallel research thread this session.)

C1. Wireshark / tshark — the one to always run

  • Built-in dissector: epan/dissectors/packet-smpp.c (source); official reference: wiki.wireshark.org/SMPP. Decodes "most of the version 3.4 specific fields," ~48 distinct TLV tags (0x0005–0x1383), and independently reassembles UDH/concatenation by handing short_message/message_payload off to Wireshark's own GSM-SMS dissector once it sees the sar_msg_ref_num/sar_total_segments/sar_segment_seqnum TLVs.
  • Port handling: SMPP has an IANA-registered port (2775/tcp, per IANA's service-names registry), but per the wiki, Wireshark's dissector does not rely on it — "No well known port is defined for this protocol. The dissector will use heuristics." Force it explicitly on a non-standard port with -d.
  • Capture + decode (flag syntax confirmed against the official dumpcap/tshark man pages): 
    dumpcap -i lo -f "tcp port 2775" -w smpp.pcapng
tshark -r smpp.pcapng -d tcp.port==2775,smpp -Y smpp -V        # verbose text
tshark -r smpp.pcapng -d tcp.port==2775,smpp -Y smpp -T json   # JSON, CI-diffable
  • Malformed-PDU flagging: two SMPP-specific expert-info fields were confirmed in source (ei_smpp_message_payload_duplicate, ei_smpp_date_time_decoding_failed); a full sweep for a generic SMPP "Malformed Packet" entry wasn't completed (file too large to fetch whole) — but Wireshark's core engine independently raises a generic "Malformed Packet" item on any dissector exception (truncated/out-of-bounds read) regardless of protocol, so malformed SMPP still typically surfaces this way.
  • Docker: no official wireshark/tshark image under Docker Hub's library/ namespace (confirmed 404). Verified working: nicolaka/netshoot (tag v0.16, pushed 2026-07-01) — its Dockerfile does apk add tshark. Fallback (verified package + current tags): 
    FROM debian:13.6-slim
RUN apt-get update && apt-get install -y --no-install-recommends tshark \
    && rm -rf /var/lib/apt/lists/*
ENTRYPOINT ["tshark"]
    (Debian trixie's tshark package is confirmed at Wireshark 4.4.18 per packages.debian.org; debian:13.6-slim and alpine:3.24.1 confirmed as current full-patch tags via the Docker Hub tag API.)

C2. sngrep-like alternatives

sngrep is confirmed SIP/RTP-only ("displaying SIP calls message flows... SIP packets... PCAP viewer") — no SMPP support, no SMPP mention anywhere. No sngrep-style interactive TUI analyzer specifically for SMPP was found — none found / unverified, not ruled out, but nothing credible surfaced.

C3. Standalone SMPP PDU decoders

Name What it is Maintenance/Licence
SMPP PDU Decoder (gurk4n) Browser tool, decodes raw hex PDUs; GSM 7-bit/8-bit, UCS2, Latin-1, ASCII; 100% client-side Unverified
isimplelab SMPP PDU decoder Part of a broader SMPP server-emulator site Unverified
sysop.fr / Ozeki decoder pages Found in search, pages unreachable this session (TLS/connection errors) Unverified
jsmpp Java library; per a (not re-fetched) Google Groups thread, newer versions log all sent/received PDUs at DEBUG — usable as a cross-check dumper Apache-2.0, active
cloudhopper-smpp demo (ClientMain.java) make client/make parser, logs raw PDU bytes (setLogBytes(true)) Apache-2.0 per README
SMPPSim smppsim.props independently exposes DECODE_PDUS_IN_LOG, CAPTURE_SME_BINARY[_TO_FILE], CAPTURE_SMPPSIM_BINARY[_TO_FILE], CAPTURE_SME_DECODED[_TO_FILE], CAPTURE_SMPPSIM_DECODED[_TO_FILE] — a genuine independent PDU log for cross-checking both directions (conf/smppsim.props) Custom freeware, non-OSI
Black Duck Defensics SMPP Server test suite Commercial fuzzer/conformance suite, 14 SMPP v3.4 message categories Commercial
Melrose Labs SMPP Analyser / conformance testing Commercial SMPP-packet analysis + PICS-based conformance service Commercial

Note: several near-identical-sounding tools (Diafaan, smspdu.be, smsdeliverer.com) decode the unrelated GSM SMS-PDU (3GPP TS 23.040 AT-command) format, not SMPP protocol PDUs — excluded above.

Ranked recommendation

Run these 3–4 clients — each catches a different class of bug, deliberately non-overlapping:

  1. jsmpp (Java) — for PDU-level/version-negotiation correctness. It silently defaults to interface_version 3.4 if your bind_resp omits sc_interface_version, but a bogus TLV value there risks an enum-lookup exception client-side — cheap way to probe how forgiving vs. fragile your bind_resp encoding is. Being "not a high-level library," it also gives you full manual control over UDH/SAR/message_payload bytes on the wire, unlike libraries that pick a strategy for you.
  2. php-smpp (alexandr-mironov fork) — for direction-enforcement and long-message wire variety. It refuses bind_transceiver outright, forcing separate TX/RX binds against your server (a different code path than a single TRX session) and is the only library found here offering all three long-message strategies (UDH, 16-bit-tag SAR, message_payload) from one client.
  3. Cloudhopper-smpp (fizzed fork, Java/Netty) — for windowing/backpressure. First-class setWindowSize/setRequestExpiryTimeout/setWindowMonitorInterval, and an async WindowFuture submission model architecturally distinct from jsmpp's synchronous style — best tool here to stress-test maxOutstanding and slow-response handling.
  4. python-smpplib (Python) — for encoding correctness. It sends GSM 7-bit unpacked for data_coding 0 by default (confirmed from source), a genuine, checkable divergence from packed-septet encoding — deliberately useful for catching a data_coding=0 decode bug either way. Its enquire_link is reactive (opt-in, fired on read-timeout) rather than timer-driven, exercising idle-handling differently than the Java options.

Honorable mention: Jasmin's smppccm (Python/Twisted, real MNO-style production tooling) is worth adding as a 5th if you want production-representative behaviour, but this session couldn't verify enough of its wire-level specifics (long-message default, exact windowing) to rank it with confidence above.

Validator to always run: Wireshark/tshark (C1). It is implementation-independent of every client above, decodes every PDU field including TLVs and UDH/concatenation reassembly, and its -T json output is scriptable for CI diffing against your own encoder's expected bytes — the only tool in this report that verifies wire encoding rather than exercising server behaviour.

View Git Blame Copy Permalink