Editing USB (section)

===Limitations===
As with all standards, USB possesses multiple limitations to its design:
* USB cables are limited in length, as the standard was intended for peripherals on the same tabletop, not between rooms or buildings. However, a USB port can be connected to a [[Gateway (telecommunications)|gateway]] that accesses distant devices.
* USB data transfer rates are slower than those of other interconnects such as [[100 Gigabit Ethernet]].
* USB has a strict [[tree network]] topology and [[Master–slave (technology)|master/slave]] protocol for addressing peripheral devices; slave devices cannot interact with one another except via the host, and two hosts cannot communicate over their USB ports directly. Some extension to this limitation is possible through [[USB On-The-Go]], Dual-Role-Devices<ref>{{cite web |url=https://blogs.synopsys.com/tousbornottousb/2018/05/03/usb-dual-role-replaces-usb-on-the-go/ |title=To USB or Not to USB: USB Dual Role replaces USB On-The-Go |last=Huang |first=Eric |work=synopsys.com |date=3 May 2018 |access-date=21 July 2021 |archive-date=25 July 2021 |archive-url=https://web.archive.org/web/20210725064610/https://blogs.synopsys.com/tousbornottousb/2018/05/03/usb-dual-role-replaces-usb-on-the-go/ |url-status=live}}</ref> and [[protocol bridge]].
* A host cannot broadcast signals to all peripherals at once; each must be addressed individually.
* While converters exist between certain [[Legacy system|legacy interfaces]] and USB, they might not provide a full implementation of the legacy hardware. For example, a USB-to-parallel-port converter might work well with a printer, but not with a scanner that requires bidirectional use of the data pins.

For a product developer, using USB requires the implementation of a complex protocol and implies an "intelligent" controller in the peripheral device. Developers of USB devices intended for public sale generally must obtain a USB ID, which requires that they pay a fee to the [[USB Implementers Forum]] (USB-IF). Developers of products that use the USB specification must sign an agreement with the USB-IF. Use of the USB logos on the product requires annual fees and membership in the organization.<ref name="JA2015"/>