Discussing it broadly: 1 gigabit equals 700 megabits.
Discussing it broadly: 1 gigabit equals 700 megabits.
Hey there, I've done some testing and gathered a lot of info. I'm planning to upgrade my networking equipment soon—currently using the ISP router. I'm looking at entry-level business or office routers. Most of these devices connect via WAN (ISP router to bridge mode) and only support speeds between 500 to 800 Mbps, even with a gigabit internet connection. Since I'm a student, I don’t want to spend too much. My main question is: how does the routing/switching capacity work on the LAN ports? Should I get a separate switch for gigabit speeds inside the local network? I tested my local speed between my server and PC using iperf3 and got about 700 Mbps. What’s the real bottleneck? Is it my PC, the router, or the LAN cables (all Cat 6)? Anyone can help me out!
Best,
Matze
P.S.: Just realized something surprising—I was thinking why I get around 1000 Mbps down but only ~700 up locally.
Cat 6 supports gigabit speeds, likely the issue lies with your router or other network-related factors.
Are these systems using the same L2? It looks like your device is on a different subnet than the server it's communicating with. There are also retries, which usually indicate network issues causing errors. Do you have a network diagram? It depends on the model. Typically, most consumer routers connect all LAN ports through a switch, making it behave similarly to an external switch. Higher-end routers for the mass market often lack this built-in switch, requiring it to be handled by the CPU.
Try some simple steps to improve performance. Check the device manager for your network card, open advanced settings, and turn off any power-saving options. Using cheaper cables or longer ones (over 25 meters) might cause issues if power-saving is active. Boost the buffer sizes on the card, ensure offloading features are on, and adjust interrupt handling—adaptive settings work best. If you manage all network devices, consider using jumbo frames at the highest supported level. A standard switch should handle full gigabit traffic without trouble, even a budget 15-20 dollar 8-port switch usually offers about 20-40 Gbps. There are many choices available for your wired setup on this HP ProBook 6570B laptop.
Generally, the issue stems from hardware limitations. When the router lacks sufficient power, it can't handle NAT at 1Gbps. Adding more advanced features like deep packet inspection further reduces the speeds supported by the device. This applies especially to high-end consumer models or products such as PFsense. My Synology RT2600AC is designed for those capabilities. Smallnetbuilder.com provides useful details, though it doesn’t evaluate every router.