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✍️ Two Separate Electronic Signature Products

ELPO e-Signature Solutions
Two Separate Products, Two Different Needs.

ELPO's two independent products in electronic signing. İmzacı — a modern desktop application for anyone who needs to sign documents. SignaturePro — a .NET library (SDK) for developers who want to embed electronic signing into their own software.

Separate products, separate users — both built by ELPO; supporting CAdES, XAdES, PAdES, ASiC standards with smart cards, USB tokens, mobile signing and timestamping. ETSI/eIDAS and Turkish Law No. 5070 compliant.

ELPO e-İmza
contract.pdf
PAdES B-LTA · long-term archive
Valid
👤
Signer · Qualified Certificate
Smart card · SHA-256 · RSA 2048
⏱️
Timestamp · KamuSM
RFC 3161 · failover active
✓ Chain & Revocation Check
OCSP + CRL · certificate trusted
İmzacı
Desktop Signing Application

İmzacı — Next-Generation Electronic Signature

Forget the old, slow, freezing signing tools. İmzacı is built from the ground up on .NET 9 and a modern UI stack, running natively on all three operating systems and detecting your smart card instantly. Drag in your document, insert your card, sign.

3
Operating Systems
4
Signature Standards
CLI
+ GUI
LTA
Archive Level
Supported Signature Profiles
CAdES BES · EPES · T · C · X · XL · A
CMS / PKCS#7 — binary document and data signatures
XAdES BES · T · C · X · XL · A
Structured signatures for XML documents and e-invoices
PAdES B-B · B-T · B-LT · B-LTA
Embedded inside the PDF, visible/invisible signatures
ASiC ASiC-S · ASiC-E
Packs the signature and documents into a single container

What legacy tools simply can't do

🖥️

Native Cross-Platform

Runs natively on Windows, Linux and macOS from a single code base. .NET 9 + Avalonia — no Java virtual machine required, lightweight to install.

💳

Event-Driven Smart Card

Detects a card the instant it is inserted or removed. Uses noticeably less CPU than legacy tools that constantly poll, and discovers the PKCS#11 library automatically.

⏱️

Multiple Timestamps + Failover

Automatic switchover and caching across KamuSM, TSE and RFC 3161 providers. If one TSA doesn't respond, signing doesn't stall — it falls through to the next.

📑

The Full Range of ETSI Profiles

CAdES (BES→A), XAdES (BES/T/C/X/XL/A), PAdES (B-B→B-LTA) and ASiC-S/E. All the way up to long-term archive (LTA) in a single application.

📦

e-Yazışma & Batch Signing

Official e-Yazışma v1.3 / v2.0 packages, KamuSM root certificate integration and folder-based batch signing — ready for enterprise document workflows.

⌨️

CLI + Scheduling (DevOps)

More than a UI; sign, verify and batch-process from the command line. With cron-like scheduling you can set up automated overnight signing pipelines.

🔌

Plugin Architecture

Custom signer/verifier plugins can be loaded. An extensible design so an organization can add its own business rules without touching the core.

🛡️

Enterprise Network & Proxy

OCSP, CRL, TSA and repository access all run through the proxy. Works seamlessly behind a corporate firewall; plus certificate revocation checks via CRL/OCSP.

SignaturePro Developer SDK · NuGet

SignaturePro — Signing Power for Your Software

Building electronic signing from scratch takes months; with SignaturePro it takes a few lines. A production-ready, modular .NET library: add only the signature standard, mobile operator or TSA provider you need as a separate package.

Program.cs
# A single package is enough for PDF signing
dotnet add package SignatureProNet.PAdES

var signer = new PAdESService();
var signature = await signer.SignAsync(
    pdf, certificate, level: SignatureLevel.BLTA);

// verify the signature
var result = await signer.VerifyAsync(signature);
🧩

Truly Modular — 39 Packages

Install only what you need. Signing PDFs only? SignatureProNet.PAdES is enough. No bloat, minimal dependencies.

🌍

Global Standards Support

European ETSI/eIDAS (CAdES/XAdES/PAdES/ASiC) in production; US FIPS, China GM/T, Russia GOST, Brazil ICP and India eSign are on the roadmap. Full Turkish Law 5070 compliance.

📱

Mobile Signature — 3 Operators

Turkcell, Vodafone and Türk Telekom mobile signature, each as a separate package. Start with a phone number, let the user approve, complete the signature.

🔐

Smart Card, USB Token & HSM

Smart card/USB token via PKCS#11 and Windows CNG. Modular integration for cloud HSM (AWS, Azure, Google) and network HSM (enterprise) providers.

🕓

11+ Timestamp Providers

KamuSM, GlobalSign, DigiCert, Sectigo, Entrust, FreeTSA and more. Each TSA is a separate package — you only reference the one you use.

Full Certificate Validation

RFC 5280 chain validation, CRL, OCSP, Delta CRL and offline validation. Bank/government-grade trust chain verification.

🔐 Signing Hardware & Services

From smart cards to cloud HSM — signs anywhere

SignaturePro doesn't care where the signing key lives: a USB token in your pocket, an enterprise HSM, or the cloud. Each provider is a separate, independent package.

💳

Smart Card & USB Token

Windows CNG + PKCS#11 — no third-party middleware required

AKİSSafeNet / eTokenGemalto / ThalesOberthur / IDEMIAAladdin / EutronFeitian / RockeyYubiKeyNitrokeySafeSignCryptoPro / RuToken
🏛️

Network HSM

High-volume signing with enterprise hardware security modules

Thales LunaUtimaco SecurityServerEntrust nShield (nCipher)
☁️

Cloud HSM

Keys in the cloud, backed by hardware assurance

AWS CloudHSM / KMSAzure Key Vault HSMGoogle Cloud KMS
📱

Mobile Signature

Qualified signing via the phone SIM — each operator a separate package

TurkcellVodafoneTürk Telekom
🕓

Timestamping (TSA)

RFC 3161 — each provider a separate package, automatic failover

KamuSMGlobalSignDigiCertSectigoEntrustFreeTSA

Brand names belong to their respective owners; SignaturePro interoperates with these devices/services through PKCS#11, CNG and the relevant APIs.

Performance

Typical signing/verification times measured on reference hardware.

~12 ms
CAdES signing (1 MB)
~18 ms
XAdES signing (1 MB)
~145 ms
PAdES signing (10 MB PDF)
~8 ms
CAdES verification
🛡️ Foundation of Trust

Full Standards Compliance

Both products — İmzacı and SignaturePro — are independently compliant with national and international electronic signature standards. Your signatures stay valid today and years from now.

ETSI EN 319 122/132/142/162

CAdES · XAdES · PAdES · ASiC European standards

eIDAS (EU) 910/2014

European electronic identification and trust services

Turkish Law No. 5070

Compliance with Turkey's electronic signature legislation

TÜBİTAK compliant

Aligned with national crypto/signature reference algorithms

RFC 3161 / 5652 / 6960

Timestamp · CMS · OCSP protocols

KamuSM integration

Root certificate and official TSA connectivity

⚡ Why ELPO?

6 things that set ELPO apart in e-Signature

A modern, fast, fully standards-compliant alternative to the heavyweight signing tools used for years — and one you can get as both an application and an SDK from a single source.

🆕

Modern .NET 9 from scratch

Unlike legacy Java-based signing tools, it was written from day one on an async/await architecture — a UI that never freezes, high throughput, easy maintenance.

🇹🇷

Local engineering, local support

A product built with ELPO engineering that understands local needs like KamuSM/e-Yazışma and provides on-the-ground support.

🤝

Two products, one vendor

İmzacı for the end user, the SignaturePro library for the developer — two separate products, but a single point of contact, one support line, one invoice.

📚

Full standards compliance

ETSI profiles from BES all the way to long-term archive (LTA/A) — your signatures stay verifiable years down the line.

🧱

Modular & extensible

39 independent packages on the SDK side, a plugin architecture on the application side. Scale as needed, carry no dead weight.

🔗

Integrated into the ELPO ecosystem

Shares the same signing infrastructure with ELPO products like e-Belge, SmartERP and Cortex — end-to-end signing across enterprise processes.

Take Your Signature Digital

Whether you sign your documents with İmzacı or embed the SignaturePro SDK into your software — the ELPO team is with you from setup to integration.

FAQ

Apakah tandatangan elektronik?

Tandatangan elektronik ialah tandatangan digital yang secara kriptografi membuktikan siapa yang menandatangani sesuatu dokumen dan bahawa ia tidak diubah selepas ditandatangani. Di bawah Akta No. 5070 (Akta Tandatangan Elektronik Turki), ia mempunyai kesahihan undang-undang yang sama seperti tandatangan basah.

Apakah İmzacı?

İmzacı ialah aplikasi desktop tandatangan elektronik moden untuk pengguna akhir yang berjalan pada Windows, Linux dan macOS. Menggunakan kad pintar/USB token, ia menandatangani dalam format CAdES, XAdES, PAdES dan ASiC; menyokong tandatangan pukal dan e-Yazışma.

Apakah SignaturePro?

SignaturePro ialah SDK tandatangan elektronik .NET bermodular untuk pembangun. Dengan 39 pakej NuGet, anda mengintegrasikan kad pintar, tandatangan mudah alih, Cloud/Network HSM dan lebih 11 penyedia cap masa ke dalam aplikasi anda sendiri.

Format tandatangan yang manakah disokong?

Format CAdES (BES→A), XAdES (BES/T/C/X/XL/A), PAdES (B-B→B-LTA) dan ASiC-S/E disokong; tandatangan boleh dilakukan sehingga tahap arkib jangka panjang (LTA).