You built a fast RAID array. You picked good drives. But when you copy a file from your NAS, the transfer crawls. Chances are your network — not your disks — is the bottleneck. This guide walks through every speed tier from 1GbE to 10GbE, shows you exactly which RAID levels outrun which Ethernet standards, and helps you decide where to spend your upgrade budget.
Ethernet Speed Tiers — What the Numbers Actually Mean
Network speeds are advertised in gigabits per second (Gbps), but storage is measured in megabytes per second (MB/s). Converting is straightforward: divide by 8. A 1 GbE link gives you roughly 125 MB/s of real-world throughput before protocol overhead. Here is how the common tiers stack up:
Standard
Line Rate
Theoretical (MB/s)
Real-World (MB/s)
Cabling
1GbE
1 Gbps
125 MB/s
~110–118 MB/s
Cat5e+
2.5GbE
2.5 Gbps
312 MB/s
~280–300 MB/s
Cat5e (short runs)
5GbE
5 Gbps
625 MB/s
~570–600 MB/s
Cat6+
10GbE
10 Gbps
1,250 MB/s
~1,100–1,180 MB/s
Cat6a / Cat7 / Fiber
Real-world throughput is lower than the theoretical maximum because of TCP/IP overhead, frame headers, and switch fabric latency. The gap is typically 5–12%, so budget for the real-world number when planning.
Will Your RAID Outrun Your Network?
A RAID array's sequential read speed depends on the number of drives and the RAID level. The table below shows when your array is fast enough to saturate — or outrun — each Ethernet standard. Values assume modern 7200 RPM CMR drives delivering ~220 MB/s each (sequential).
RAID Level
4 Drives
6 Drives
8 Drives
Bottleneck?
RAID 0
~880 MB/s
~1,320 MB/s
~1,760 MB/s
10GbE+ recommended
RAID 5
~660 MB/s
~1,100 MB/s
~1,540 MB/s
5GbE–10GbE
RAID 6
~440 MB/s
~880 MB/s
~1,320 MB/s
2.5GbE–10GbE
RAID 10
~440 MB/s
~660 MB/s
~880 MB/s
2.5GbE–5GbE
Heads-up: A single 1GbE link (125 MB/s) is saturated by almost any multi-drive array. If you have four or more drives in any RAID configuration, Gigabit Ethernet is your bottleneck. Upgrading to at least 2.5GbE is the single most impactful change you can make.
SMB Multichannel vs. Link Aggregation
When one port is not enough, you have two common ways to combine multiple network interfaces. They work very differently:
SMB Multichannel
Built into SMB 3.0+ (Windows 8/Server 2012 and later, Linux via Samba 4+). Automatically uses all available NICs for a single file transfer. No switch configuration needed. Works with any switch, including unmanaged ones. Can stripe a single large file across both links — a true speed multiplier.
Best for: Homelabs and small offices where you want simple multi-gig performance without managed-switch complexity.
Link Aggregation (LACP / 802.3ad)
Combines multiple physical links into one logical link. Requires a managed switch and configuration on both ends. Uses a hashing algorithm (usually MAC/IP/port-based) to distribute connections — a single TCP stream is pinned to one link, so individual file transfers do not get faster. Helps when many clients connect simultaneously.
Best for: Multi-client environments where aggregate bandwidth matters more than single-stream speed.
For a home NAS with one or two heavy users, SMB Multichannel is simpler and often more effective. If you have a managed switch already and many simultaneous clients, LACP is still a solid choice — but do not expect it to speed up a single file copy.
Switch & NIC Recommendations
The network path is only as fast as its slowest segment. Here are brand-neutral considerations for each tier:
1GbE
Virtually any switch works. Integrated motherboard NICs are fine. This tier is dirt cheap and everywhere, but extremely easy to saturate with modern drives.
2.5GbE / 5GbE
The sweet spot for home NAS. Multi-gig NBASE-T switches are increasingly affordable. Many newer motherboards include 2.5GbE. PCIe NICs are under $50. Works over existing Cat5e at shorter distances.
10GbE
Requires Cat6a or fiber. PCIe NICs cost $100–300; switches are the biggest expense ($300+). Direct-attach copper (DAC) cables are the most cost-effective for short runs between a NAS and a workstation.
Pro tip: For a two-machine setup (NAS + workstation), skip the switch entirely and use a direct DAC or fiber connection with static IPs. Add a second 1GbE link to your LAN for internet access. This is the cheapest path to 10GbE.
Frequently Asked Questions
How do I know if my network is the bottleneck?
Run a local benchmark on your NAS (e.g., fio ordd to measure disk read speed without the network), then copy a large file over SMB or NFS. If the network transfer is significantly slower than the local disk read, your network is the bottleneck. Use the RAID Calculator to estimate your array's throughput and compare it to your Ethernet standard.
Is 2.5GbE enough for a home NAS?
For most home users, yes. A 2–4 drive RAID 5 or RAID 10 will peak at 300–600 MB/s, and 2.5GbE delivers ~280–300 MB/s real-world. That is more than enough for 4K Plex streams, large file transfers, and backups. If you have 6+ fast drives or run NVMe-based storage, step up to 5GbE or 10GbE.
Can SMB Multichannel work with a single 2.5GbE port?
No — SMB Multichannel requires at least two network interfaces to provide any benefit. However, you can combine a 2.5GbE port with a 1GbE port (on the same subnet) to get aggregate throughput. The practical result is not the full sum (3.5 Gbps), but it does improve multi-stream performance.
Do I need a managed switch for 10GbE?
Not strictly. Many 10GbE switches come in unmanaged or "smart managed" variants that work out of the box. A fully managed switch is only necessary if you need VLANs, link aggregation, flow control tuning, or jumbo frame configuration across multiple VLANs. For a simple flat network, an unmanaged 10GbE switch is perfectly fine.
Put the Numbers to Work
Run the numbers for your own hardware. Our calculators and guides help you size your network before you buy: