SmppSharp 1.4.1

SmppSharp

Lightweight SMPP 3.4 client for .NET 8+. No external dependencies.

Features

• Text SMS — auto-detect GSM7 (Latin) or UCS2 (Cyrillic, Arabic, Chinese, Hebrew, Greek, emoji)
• Long messages — automatic multipart splitting via UDH (default), SAR TLV, or message_payload TLV
• Flash SMS — Class 0 messages displayed immediately without storing
• Binary SMS — raw byte payload (OTA configs, ringtones, etc.)
• WAP Push — Service Indication (SI) with URL and message text
• Fluent builder — intuitive SubmitRequestBuilder API
• MO & delivery receipts — receive incoming messages and status reports
• Bulk sending — SubmitBulkAsync with concurrency control
• Pipeline mode — SubmitPipelineAsync for high-throughput campaigns (> 1000 msg/sec)
• SSL/TLS — optional encrypted transport
• Auto-reconnect — configurable delay and retry limit
• Keepalive — automatic enquire_link heartbeat
• Diagnostic Metrics — System.Diagnostics.Metrics integration (OpenTelemetry, Prometheus)
• ASP.NET Core DI — AddSmpp() extension with IHostedService

Installation

dotnet add package SmppSharp

Quick start

var client = new SmppClient(new SmppOptions
{
    Host     = "smpp.provider.com",
    Port     = 2775,
    SystemId = "login",
    Password = "password",
});

client.OnMessageReceived  += async msg     => Console.WriteLine($"MO: {msg.SourceAddress} → {msg.Message}");
client.OnDeliveryReceived += async receipt => Console.WriteLine($"DR: {receipt.MessageId} = {receipt.Status}");
client.OnDisconnected     += ex            => Console.WriteLine($"Disconnected: {ex?.Message}");
client.OnReconnected      +=               () => Console.WriteLine("Reconnected!");

await client.ConnectAsync();

var result = await client.SubmitAsync(new SubmitRequest
{
    SourceAddress      = "MYAPP",
    DestinationAddress = "+998901234567",
    Message            = "Ваш код: 1234",
});

Console.WriteLine($"Sent! MessageId={result.MessageId}, Segments={result.SegmentCount}");

Fluent builder

var request = new SubmitRequestBuilder()
    .From("PAYOMAK")
    .To("+998901234567")
    .Text("Ваш код: 4521")
    .WithDeliveryReport()
    .WithCorrelationId("order-99")
    .ValidFor(TimeSpan.FromHours(24))
    .Build();

await client.SubmitAsync(request);

Flash SMS

Displayed immediately on the handset — not saved to inbox.

var request = new SubmitRequestBuilder()
    .From("ALERT")
    .To("+998901234567")
    .Text("Внимание! Ваш счёт заблокирован.")
    .Flash()
    .Build();

await client.SubmitAsync(request);

Binary SMS

var request = new SubmitRequestBuilder()
    .From("SVC")
    .To("+998901234567")
    .Binary(new byte[] { 0x01, 0x02, 0x03, 0xAB })
    .Build();

await client.SubmitAsync(request);

WAP Push

Sends a Service Indication (SI) — opens a URL on the user's handset.

using SmppSharp.Builders;

var request = WapPushBuilder.CreateSi(
    sourceAddress:      "PAYOMAK",
    destinationAddress: "+998901234567",
    url:                "https://payomak.uz/promo",
    message:            "Нажмите для просмотра акции",
    signal:             WapPushSignal.Medium);

await client.SubmitAsync(request);

Available signals: None, Low, Medium, High, Delete.

Bulk sending

var requests = phones.Select(phone => new SubmitRequestBuilder()
    .From("PAYOMAK")
    .To(phone)
    .Text("Акция! Скидка 20% до конца месяца.")
    .Build());

var results = await client.SubmitBulkAsync(requests, maxConcurrency: 20);
Console.WriteLine($"Sent: {results.Count}");

High-throughput pipeline (> 1000 msg/sec)

Streams requests and yields results as they complete — no need to buffer everything in memory.

var requests = GetRequestsAsync(); // IAsyncEnumerable<SubmitRequest>

await foreach (var result in client.SubmitPipelineAsync(requests, concurrency: 100))
{
    Console.WriteLine($"Sent: {result.MessageId} ({result.SegmentCount} segments)");
}

SSL/TLS

var client = new SmppClient(new SmppOptions
{
    Host     = "smpp.provider.com",
    Port     = 3550,
    SystemId = "login",
    Password = "password",
    UseSsl   = true,
    // SslTargetHost            = "smpp.provider.com", // optional, defaults to Host
    // AllowUntrustedCertificate = true,               // dev only
});

ASP.NET Core DI

// Program.cs
builder.Services.AddSmpp(opt =>
{
    opt.Host     = "smpp.provider.com";
    opt.Port     = 2775;
    opt.SystemId = "login";
    opt.Password = "password";
});

// Inject ISmppClient wherever needed
public class SmsService(ISmppClient smpp)
{
    public Task SendAsync(string phone, string text) =>
        smpp.SubmitAsync(new SubmitRequest
        {
            SourceAddress      = "MYAPP",
            DestinationAddress = phone,
            Message            = text,
        });
}

Observability (OpenTelemetry / Prometheus)

// Register metrics listener
builder.Services.AddOpenTelemetry()
    .WithMetrics(m => m.AddMeter(SmppMetrics.MeterName));

Available instruments:

Configuration reference

new SmppOptions
{
    Host                     = "localhost",
    Port                     = 2775,
    SystemId                 = "",
    Password                 = "",
    SystemType               = "",
    BindMode                 = BindMode.Transceiver, // Transmitter | Receiver | Transceiver
    EnquireLinkInterval      = TimeSpan.FromSeconds(30),
    ResponseTimeout          = TimeSpan.FromSeconds(30),
    ReconnectDelay           = TimeSpan.FromSeconds(5),
    AutoReconnect            = true,
    MaxReconnectAttempts     = 0,   // 0 = infinite
    UseSsl                    = false,
    SslTargetHost             = null,
    AllowUntrustedCertificate = false,
    UseUdh                    = true,   // multipart via UDH; false = SAR TLV
    UseMessagePayload         = false,  // send long message as single PDU via message_payload TLV
}

License

MIT