Technical Requirements

To use Shred Stream effectively, you need:

Infrastructure

• Public IP with open UDP port (no NAT/CGNAT)

• Low-latency server close to Thor Labs RPC Nodes (recommended: Frankfurt)

• Sufficient bandwidth (~50-100 Mbps for full shred stream)

Development Capability

• Deshredding logic to reconstruct transactions from shred fragments

• FEC decoding (optional) to recover from packet loss

• Custom parsing for your specific use case

Example Client (Go)

shred_listener.go

package main

import (
    "encoding/binary"
    "fmt"
    "net"
)

// Solana shred header offsets (per spec)
const (
    OffsetVariant = 64 // 0x40: Shred variant (1 byte)
    OffsetSlot    = 65 // 0x41: Slot number (8 bytes, u64 LE)
    OffsetIndex   = 73 // 0x49: Shred index (4 bytes, u32 LE)
)

func main() {
    addr, _ := net.ResolveUDPAddr("udp", ":9000")
    conn, _ := net.ListenUDP("udp", addr)
    defer conn.Close()

    buf := make([]byte, 1232)

    for {
        n, _, err := conn.ReadFromUDP(buf)
        if err != nil {
            continue
        }

        shred := buf[:n]
        variant := shred[OffsetVariant]
        slot := binary.LittleEndian.Uint64(shred[OffsetSlot : OffsetSlot+8])
        index := binary.LittleEndian.Uint32(shred[OffsetIndex : OffsetIndex+4])

        fmt.Printf("slot=%d index=%d variant=0x%02x size=%d\n",
            slot, index, variant, n)
    }
}

This example listens on UDP port 9000 and parses the variant, slot, and index fields from each received shred according to the Solana shred header offsets.

Shred Format

Per the Solana shred specification:

Offset	Size	Field
0x00	64	Signature (Ed25519)
0x40	1	Variant (encodes type + auth method)
0x41	8	Slot (u64 little endian)
0x49	4	Index (u32 little endian)
0x4D	2	Version (u16 little endian)
0x4F	4	FEC Set Index (u32 little endian)
0x53+	varies	Type-specific header + payload

The variant byte encodes both the shred type (data/coding) and authentication method (legacy/merkle) as two 4-bit values.

Maximum shred size: 1228 bytes (fits in a single UDP packet). Ensure your UDP buffer and networking configuration can handle this size and the expected throughput (~50–100 Mbps).